(TRESSAUD) INTL. SYMPO. ON SOLID STATE CHEMISTRY FOR APPLICATIONS AND SUSTAINABLE DEVELOPMENT

To meet the high-energy requirements that can enable the 40-mile electric drive plug-in hybrid electric vehicle (P-HEVs), long range electric vehicle (EV) and smart grid, it is necessary to develop very high energy and high power cathodes and anodes that, when combined in a battery system, must offer over 5,000 charge-depleting cycles, 15 years of calendar life as well as excellent abuse tolerance. These challenging requirements make it difficult for conventional battery systems to be adopted in P-HEVs and EVs. In this talk, we will first introduce the next generation lithium ion battery that include the Ni rich full gradient cathode [1], a high voltage and nonflammable Fluorinated based electrolyte and Silicon-graphene composite anode including a novel pre-lithiation technology to overcome the irreversible loss of this anode in the first cycle . We will then finish by describing a novel lithium superoxide based on a close battery system that offers at least 3 times the energy density of the state of the art lithium ion battery [2-3] and a SeS system with novel electrolytes that suppress the dissolution of polysulfide species [4].

Coordination polymers are built up from the association of metallic centers with organic (e.g. O- or N-donor) ligands. For the last two decades, this assembling concept has been applied for the generation of the so-called Metal-Organic Frameworks (MOFs), which have been investigated for many potential applications in various domains like catalysis, gas storage, optics or medicine. Recently, the strategy has been successfully used with the particular case of actinides (An) [1]. Most of the studies have mainly reported the synthesis of such solid open-framework networks bearing U(VI) or Th(IV), while trans-uranium elements have been much less studied due to their high radiotoxicity and limited amount of source material. Among the possible oxidation states of An, the tetravalent state has been investigated less actively and large polyoxo clusters have been isolated for U or Pu. In contrast, there is not much data concerning Np(IV) compounds.
In the present talk, we firstly present the formation of several series of uranyl-organic frameworks associated to poly-carboxylate linkers, by following the pH variation parameter of the reaction medium, related to the hydrolysis rate. This strategy was then applied to actinides(IV), which are known to exhibit a strong affinity for the hydrolysis reaction in order to form inorganic entities with high nuclearities. In this approach, the control of water content in reaction media containing organic solvent will be investigated in different chemical systems with Th(IV) and U(IV) [2] in the presence of dicarboxylic acids molecules (typically terephthalic acid), and was then extended to Np(IV) for some cases [3]. The structural descriptions of the different coordination polymers will point out the nuclear variation of the inorganic bricks from mononuclear [AnO ₉] up to hexanuclear entities [An ₆O ₈]. The latter is observed in the well-known series of UIO-66(Zr) MOF compounds.
The second strategy was to use prototypical MOFs (MIL-n, UiO-66, ZIF-8) for the capture of radioactive molecules generated during a nuclear accident like iodine derivatives (I ₂, CH ₃I) or actinides (U, Th) [4]. In each case, the MOF compounds exhibit very high sorption capacities, modulated by the size of the pores and the functionalization of the framework. The resistance of MOF compounds under irradiative conditions (gamma ray irradiation) will be also discussed [5].

Carbon nanotubes and graphene are almost perfect molecules with truly amazing combinations of thermal, electrical and structural properties. In order to achieve their full potential, they need to be fully integrated hybrid materials in all sorts of matrices. Full integration requires their development beyond conventional composites so that the level of the non-nanomaterial is designed to integrate fully with the amount of nanotubes and graphene. Here the nanomaterials are part of the matrix rather than a differing component, as in the case of conventional composites. In order to advance the development of multifunctional materials and to integrate nanotubes and graphene, this research is focused on the simultaneous control of the nano-architecture, structural properties, thermal and electrical conductivity of fully integrated hybrid materials. These hybrid material systems are designed to surpass the limits of the rules of mixtures in conventional composite design. The goals are to implement multifunctional designs to fully mimic the properties of carbon nanotubes and grapheme on larger scales for enhanced thermal and electrical management in addition to the control of other properties such as strength, toughness energy and power. These new approaches involve exfoliation, functionalization, dispersion, stabilization, alignment, polymerization, reaction bonding and coating in order to achieve full integration. Typical examples of structural applications of polymeric and ceramic matrices and applications in energy systems such as capacitors and batteries as well as other material systems are presented and discussed.

The growing demand of new and sustainable consumer printed electronics led to the increased interest in devices integrating natural materials. Here we present the wok resulting from recent research concerning the application of cellulose based materials in flexible electronic devices. First topic is related to with the development of electrolytic membranes to be used as dielectric in transistors exploring the high capacitance that can be obtained by the formations of electric-double layers. Second topic to be addressed are printable inks based on commercial carbon fibers and zinc oxide nano-particles mixed with some cellulose derivatives that were optimized to create printed active layers at temperatures lower than 150 °C. This allowed the development of fully screen-printed sensors and transistors with mobility above 10 cm²V^-1s^-1 and on/off current ratio higher than to 10⁵ on substrates like paper and cork. Finally, we will show how cellulose nano-crystals can self-assemble in a chiral nematic structures that mimic those existing in nature. These can be then used as dielectric in field effect transistors making possible the detection of circular polarized light in such devices.

Smart materials are the salient feature of our modern e-connected society. Among them, optical materials are continuously evolving and finding more areas of application, such as the electrochromic windows in the Boeing 787 Dreamliner and Gentex Corporation’s antiglare mirrors. Electrochromic smart windows can be used in cars or buildings to adjust brightness or in spacecraft to moderate the intense thermal fluctuations by switching between light/infrared transmission and reflection. Electrochromic materials and devices change their optical properties in a reversible and persistent way under an applied voltage¹. The most frequently used electrochromic compounds include transition metal oxides, such as WO₃, MoO₃, TiO₂, IrO₂, V₂O₅, NiO, Prussian blue (iron ferrocyanide) analogues and organic polymers, such as polyaniline, polypyrrole, and polythiophen. Inorganic electrochromic materials are stable and WO₃ is central to most applications, however their range of available colors and brightness are limited. On the contrary, organic polymers show high color efficiency and a huge range of colors but suffer from limited stability-particularly when exposed to the ambient environment.
Aiming at improving EC properties for displays applications, our approach combines hybrid materials and novel design for ambient air and room temperature fabrication. In this presentation, focusing in particular on enlarging the palette of color, the advantage of mixing oxides and polymers will be demonstrated. As an example, the addition of iron oxide on poly(3,4-ethylenedioxythiophen), allows to switch not only from light to deep blue but also from blue to red². An additional step towards multichromism can be achieved by using vanadium oxides based devices reaching color modulation from orange to green and blue³.
Acknowledments : This activity included in the SUPERSMART project has received funding from the European Institute of Innovation and Technology (EIT). This body of the European Union receives support from the European Union’s Horizon 2020 research and innovation program.

In this presentation it will be shown, through examples chosen in the field of Solid State Chemistry based (i) on light p elements (B,C,N), a proposition of a new ultra-hard carbon nitride C2N1 and (ii) on p and 3d elements (B,Cr), a new di-chromium hexaboride Cr2B6 exhibiting a 2D boron network,. in addition to the phases identified experimentally: Cr2B, Cr5B3, CrB, Cr3B4, Cr2B3 and CrB2. Investigation and concepts first arising from experimental observables are shown to be aided and accelerated via First Principle calculations of energy and energy related quantities and the electron transfer and electron localization between atoms will be illustrated by using the electron localization function (ELF)2,3.

In recent years, caloric effects near phase transitions in solids have attracted growing interest from investigators. First, this is due to the possibility of obtaining information about a direct relationship between fundamental values such as entropy, temperature, order parameter, structural disorder and sensitivity to external fields (electric, magnetic, mechanical stress and hydrostatic pressure). [1,2] The second reason is associated with the actual problem of searching for high-performance solid refrigerants and for designing alternative refrigeration cycles which are competitive compared to the traditional vapor-compression cycles. [3,4]
Barocaloric effect (BCE) associated with the reversible change in the entropy/temperature, ΔS_BCE / ΔT_AD, under pressure variation under the isothermal/adiabatic conditions is a common caloric characteristic for substances of different physical nature.
We performed the analysis of the extensive and intensive BCE in some complex fluorides and oxyfluorides which are very sensitive to a change of the chemical pressure and very often undergo successive order-disorder phase transitions of a ferroelastic nature. Different types of the T - p phase diagrams, including the triple points, are considered in connection with the complicated dependences of T(p) observed experimentally. Analyzed diagrams do not cover all possible variants of the phase transition temperature behavior under pressure. They show, however, which parameters of the phase transitions and phase diagrams should be taken in consideration when analyzing BCE. A very important point is that rather low hydrostatic pressure practically does not affect the entropy of the ferroelastic transformations. Therefore, the behavior of extensive and intensive BCE is not changed with increase in pressure. In the case of close temperatures of the successive phase transitions, there is a possibility to realize extensive BCE as the sum of entropies of two transformations. Due to the large magnitude of the extensive and intensive BCE, complex fluorides and oxyfluorides can be considered as new competitive solid refrigerants.

The knowledge we have developed through the synthesis and experimental study of extended solids allows us to efficiently identify new materials. In many cases, this knowledge includes scientifically interesting or technically important changes in properties. An example is the chemical control of the transparent conducting behaviour of correlated metals (1), evaluated as epitaxial films through optical and transport data. The selection of d0 cations to stabilise oxygen-oxygen bond formation upon deep oxidation of lithium ion cathodes is another example (2). Here, computation provides underpinning guidance in the selection of experimental targets.
The large potential range of accessible compositions and structures, however, challenges our present capabilities. As part of the current interest in exploring computationally-enabled routes to new materials, we are developing computational tools for the identification of stable new compositions. We have recently (3) been able to predict ab initio the regions of composition space that afford new materials. We then subsequently isolate those materials experimentally, using the computation of the energies of probe structures identified by new crystal structure prediction methods (4) to explore the space. The presentation will discuss the potential offered by informatics approaches often referred to as machine learning in such work.

Based on a combination of various first-principles methods, we propose various kinds of layered materials. One is tetragonal GeP2, which has optimal band offset for photocatalyzed CO2 decomposition in wide pH range.[1] The second one TeSe2, which exhibits phase polymorphism, phase transition on charge doping, ferroelectricity, and interesting spin texture.[2,3] I also describe a series of my recent collaborations with an experimental group. First, combined experimental and theoretical effort is described for an efficient photoelectrochemical (PEC) water splitting of p-GeAs/n-Si heterojunction based on the band alignment, buildup of space charge in the junction, and the band bending of the n-Si at the electrolyte interface.[4] Second, our extensive DFT calculation complemented by analysis of charge transfer, band structure analysis, and reaction path for Volmer-Heyrovsky reactions give a deep insight into our experimental results, which has shown that the 1T'-phase guest-intercalated MoS2/WS2 nanosheets synthesized by one-step hydrothermal reaction exhibit excellent stability as well as higher catalytic activity toward the hydrogen evolution reaction at specific guest concentrations.[5-7] Finally, our extensive ab initio molecular dynamics simulations not only reproduce collaborative experimental voltage-charge capacity curves for WS2@graphite and WS2@nitrogen-doped graphite composites in lithium ion battery but also gives us a detailed picture on the structural evolution in the charge-discharge process.[8]

The author of this work basing on her own investigations of Li_xMO₂ cathode materials ( M=Ni, Co, Mn, Cu) has demonstrated that the chemical disorder influenced on electronic structure of these materials plays an important role in the electrochemical intercalation process [1].
The paper reveals correlation between chemical disorder, crystal and electronic structure, transport and electrochemical properties of layered Li_xCoO₂, Li_xNi_1-y-zCo_yCu_zMn_0.1O₂ and Na_xCoO_2-y [2] cathode materials and explains of apparently different character of the discharge/charge curve in those systems. Comprehensive experimental studies of physicochemical properties of Li_xNi_1-y-zCo_yCu_zMn_0.1O₂ and Na_xCoO_2-y cathode materials (XRD, electrical conductivity, thermoelectric power) are supported by electronic structure calculations performed using the Korringa-Kohn-Rostoker method [3] with the coherent potential approximation (KKR-CPA) to account for chemical disorder. It is found that even small O defects (~1%) may significantly modify DOS characteristics via formation of extra broad peaks inside the former gap leading to its substantial reduction. Moreover, these DOS peaks of “defects” strongly evolve with Li and Na contents, actually leading to the overall reducing of the gap and to even the pseudogap.
The battery on the base on the developed LiNi_0.9-y-zCo_yMn_0.1Cu_zO₂ cathode materials are characterized by high potential, high capacity and high rate capability guaranteeing high energy and power densities.
This work was funded by the National Science Centre Poland (NCN) under the “OPUS 12 programme on the basis of the decision number UMO- 2016/23/B/ST8/00199.

The focus of this talk will be on the question: how does the metal/oxide interface modify the activity and selectivity of supported noble metal catalysts? Specifically, we utilize the variable strength of interaction between different perovskite oxide supports and noble metal catalysts. The lattice parameters of LnScO₃ match well with several noble metals, which allows for a systematic study of how certain support properties can affect the catalytic performance of these metals. Lanthanide scandates were produced through a low-temperature heat treatment of a stoichiometric hydroxide gel (sol-gel) in a humid environment. (1) Water vapor was necessary to preserve the higher diffusivity of the gel, but an excess of water vapor led to the formation of secondary phases. The temperature of the reaction was used to tune the Gibbs free energy of reaction and kinetics of particle growth to produce faceted nanoparticles. Hydrothermal synthesis of SrTiO₃, for example, may produce materials that are controllably terminated with SrO-rich {100}, TiO₂-rich {100}, or TiO₂-rich {110} surfaces. Supported Pt nanoparticles, which have a close lattice match to SrTiO₃, showed a higher selectivity in acrolein hydrogenation towards allyl alcohol on SrTiO3 than BaTiO₃ when the Winterbottom shape on SrTiO₃ had a higher ratio of facets to edges or corners. Exploiting the Strong Metal-Support Interaction further improves the selectivity. (2,3)

The possibility to modify inorganic oxides at moderate temperatures, under kinetic rather than thermodynamic control leads to metastable structural rearrangements with novel electronic partitions and original properties. In most cases, the abundant literature reports modifications of the anionic sub-array dealing with anionic vacancies, interstitials or anionic exchanges. However, intercalation or morerare exsolution cases show exotic cationic modifications towards original intercalated/depleted phases. The Fe²⁺/Fe³⁺ redox properties stand ideally for easy in-lab reactions. For instance, the controlled oxidation of the 2D-ising ferromagnetic BaFe²⁺₂(PO₄)₂ into Fe-depleted BaFe₂/3+2-x(PO₄)₂ (x<0.66) leads to a series of intermediate phases with full vacancy/Fe ordering and to nanometric Fe₂)O₃) [1]. On the opposite, playing redox chemistry in 2D-oxides such as the multiferroic, YbFe_2.5+2O₄ and Yb₂Fe_2.66+3O₇, the metal content is maintained but re-organized during reduction/oxidation very similarly to the hexagonal YMn³⁺O₃ system [2,3]. Generally, all transformed compounds require complex crystal-chemistry features with occurrence of supercells, modulated structures, and/or disordered intergrowths. The possibility to tune, in a controlled way, various pristine frameworks opens a wide field of investigation for tailor-made crystallographic architectures within the field of giant anion/cation-labile systems.

Titanium dioxide (TiO₂) is one of the most attractive materials during the last decades because of its variety of practical applications such as photocatalysis, amphiphilic coatings, and dye-sensitized solar cells. So far, numerous TiO₂ nanostructures have been prepared such as spheres, films, nanowires, nanofibers, and nanotubes. In addition to the trend of nanostructural fabrication, the microarchitecture of TiO₂ has become a new paradigm in recent materials, chemistry, and nanotechnology [1]. Ammonium oxofluorotitanate (NH₄TiOF₃) crystals have been intensively studied and used as precursors for the synthesis of highly ordered and morphologically controlled TiO₂ [2]. It has been found that co-doping of nonmetal (especially with N and F) and metal (Fe) elements is capable of extending the light absorption edge of TiO₂ to the visible light region and improving photocatalytic activity due to the synergistic effect [3, 4]. For the large-scale applications of such materials, their mass quantity is required. In this case, the fluoride processing of the most abundant natural mineral ilmenite (FeTiO₃) with solid NH₄HF₂ (m. p. 126 ^oC) can be used. We have carefully studied this process [5]. Fluorination reactions of raw materials with NH₄HF₂ are thermodynamically possible and proceed exothermally (even at room temperature). Fluorination products are mainly nonstoichiometric phases of high symmetry: tetragonal double salts of silicon and titanium (NH₄)₃[Si(Ti)F₆]F, cubic fluoroelpasolites and fluoroperovskites, which were isolated in a single crystal form and their crystal structures were determined (or refined). Their phase transitions at temperature decreasing, thermal and hydrolytic properties were studied. The compounds were investigated by X-ray diffraction, differential thermal analysis (DTA), differential scanning microcalorimetry (DSM) and adiabatic calorimetry, NMR, infrared, Raman, XPS, and Mössbauer spectroscopies. The tensimetry method was also used for establishment of incongruent sublimation of (NH₄)₂SiF₆.
Comparative analysis of fluoride processing methods of titanium-containing raw materials indicates the preference of NH₄HF₂ use.

Inorganic fluoride materials constitute an important part of solid-state chemistry since they are present today as components in many advanced technologies, for instance in energy storage devices, such as Li-ion batteries, F- ion-based all-solid-state batteries, or fuel cells. Beside this type of applications, fluoride materials are also decisive components in microphotonics, fluorescent chemical sensors, solid-state lasers, nonlinear optics, bio- and medicinal technologies, etc [1]. Most of these outstanding properties can be correlated to the exceptional electronic properties of the element "Fluorine" [2].
The strategic importance of inorganic fluoride materials will be illustrated by some examples:
- In energy storage and conversion fields, fluorinated carbon nano-particles (F-CNPs) have been tested as active materials in electrodes of primary lithium batteries, whereas in secondary Li batteries, 3d-transition metal fluorides and oxyfluorides are proposed as active electrodes.
- Among the huge variety of solid-state d-transition metals, fluorides derived from the perovskite, layered BaCuF₄ and iron fluorides (TTB- K₃Fe₅F₁₅), are noticeable multiferroics, in which magnetism and ferroelectricity coexist.
- Functionalization processes and surface modifications using various fluorination treatments yield nano-sized materials with very high surface areas. In the case of fluorinated nano-carbons, the physical properties that can be drastically modified may concern: electrical conductivity, varying from insulating to metallic behavior, switchable hydrophobic/hydrophilic surfaces of substrates treated with fluorinated rf plasmas, high mobility in FET systems involving fluoro-graphene, and new kinds of fluorinated nano-carbons providing higher potential and energy density values, and thus improving the electrochemical performances of primary Li-battery.
Concerning environmental and sustainable issues, new alternatives are proposed to substitute CFCs, HFCs and PFCs by molecules much favorable for our troposphere because of their lower GWP. In many fields such as the ceramics industry or aluminum production, new technologies allow to considerably lower the level of fluorine and fluoride emission or wastes. Finally, in areas of the world where the level of fluorine in water is dangerously high, various de-fluoridation processes improve the quality of drinking water, lower the risks of fluorosis, and bringing most promising development for these populations [3].

References:
[1] "Progress in Fluorine Science", A. Tressaud Series Editor, Elsevier, USA Vol. 1 - "Photonic & Electronic Properties of Fluoride Materials", A.Tressaud & K. Poeppelmeier Eds. (2016) ; Vol. 2 - "New Forms of Fluorinated Carbons", O. Boltalina & T. Nakajima, Eds. (2016); Vol. 3 " "Modern Synthesis Processes and Reactivity of Fluorinated Compounds", H. Groult, F. Leroux & A. Tressaud, Eds. (2017); Vol. 4 - "Fluorine & Health: Pharmaceuticals, Medicinal Diagnostics, and Agrochemicals", G. Haufe, & F. Leroux Eds. (2018).
[2] Fluorine Chemistry, a thematic issue, Chemical Reviews, V. Gouverneur, K. Seppelt, Eds., Chem. Rev. 115 (2015) 563-1306.
[3] "Fluorine and the Environment", Vol.1: F-emissions and atmospheric chemistry. Vol.2: Green Chemistry, Water, Agriculture, and Analytical aspects, Advances in Fluorine Science Series, A. Tressaud, Ed. Elsevier (2006)

The ever-growing application of deep-ultraviolet (deep-UV, I� < 200 nm) nonlinear optical (NLO) materials in various fields requires searching for candidates to generate the deep-UV lasers through direct second-harmonic generation (SHG) method. Among them, fluorooxoborates, benefiting from the large optical band gap, high anisotropy and ever-greater possibility to form non-centrosymmetric structures activated by the large polarization of the functionalized [BO_xF_4-x]^(x+1)- (x =1, 2 and 3) building blocks, have been considered as the new fertile fields for searching the deep-UV NLO materials.^1,2 Two series of fluorooxoborates AB₄O₆F (A = NH₄, Na, Rb, Cs, K/Cs and Rb/Cs)^3-6 and MB₅O₇F₃ (M = Ca and Sr)^7,8 were rationally designed and synthesized, which not only inherit the favorable structural characteristics of KBBF, but also possess superior optical properties. Property characterizations reveal that these two series possess the optical properties (deep-UV cutoff edges, large SHG responses, improved growth habit and also large birefringence to ensure the phase matching behavior in the deep-UV spectral region, etc.) required for the deep-UV NLO applications, which make them potential candidates to produce the deep-UV coherent light by the direct SHG process.

HQ-CNRS started work on lithium metal with polymer electrolyte in lithium rechargeable batteries in 1979. Since that time, battery research has expanded worldwide. Several new polymers, solid electrolytes and ionic liquids with improved conductivity have resulted from a better understanding of the major parameters controlling ion migration, such as favorable polymer structure, phase diagram between solvating polymer and lithium salt, and the development of new lithium counter-anions. In spite of the progress so far, the quest for a highly conductive dry polymer at room temperature is still continuing and all-lithium polymer battery (LPB) developers presently face the challenge of whether to heat the PEO-based polymer electrolyte to enable high-power performance, as required for electric vehicle and energy storage or develop a polymer electrolytes conductive at RT. LPB developers have explored both the high-temperature and low-temperature options.
This presentation provides an overview and progress in developing three battery technologies:
1. Lithium-metal-based batteries made from dry polymer and ionic liquid-polymer electrolytes for rechargeable lithium batteries with olivine (LFP and LMFP).
2. All solid-state batteries using Li°-NMC.
3. High voltage composite polymer- ceramic for all solid state batteries.
We compare the performances the energy density, the cost, and safety of li-ion batteries vs. solid state batteries. In this presentation we will explain the process from materials to the system (cell, module and pack).

Numerous studies have been performed these last three decades on perovskites and derivatives showing the possibility to create and to tailor exciting physical properties. This has been previously exemplified by the high Tc superconducting cuprates, the colossal magnetoresistance manganates and the thermoelectric cobaltates. Herein we describe several new classes of materials that appear most promising for the generation of attractive physical/ chemical properties and applications.
Multiferroic materials, involving the coexistence of ferroelectricity and ferromagnetism, have been the object of numerous investigations due to their potential application for memory devices. In this respect, oxides with a triangular sub-lattice present a rich potential which to date has not been fully investigated. The mixed valent "114" tetrahedral cobaltates open the route to attractive multiferroic properties as exemplified by the magneto-electric ferrimagnet CaBaCo₄O₇ which exhibits gigantic magnetic field induced polarization and high magneto-electric coupling. Beside oxides, Hybrid organic-inorganic frameworks (HOIF) represent an important source for the realization of multiferroic properties which has been, to date, insufficiently explored. In particular, transition metal phosphonates with a layered structure offer a potential for the realization of magneto-electric properties by coupling spins of the inorganic layers with electric dipoles of the organic layers. This is illustrated by the non-centro symmetric layered metal-phosphonate, MnO₃PC₆H₄Br.H₂O, whose structure consists of perovskite layers stacked with organic bromo-phenyl layers. This compound has been designed from the layered phosphonate MnO₃PC₆H₅.H₂O; It exhibits complex magnetic features which are exactly captured in T and H-dependent dielectric constants, ɛ'(T) and ɛ'(H). This demonstrates direct ME coupling in this designed hybrid and yields a new path to design a magnetoelectric hybrid.
Low dimensional magnets, especially single molecule magnets (SMM) and single chain magnets (SCM) have been thoroughly investigated in metal organic frameworks in view of applications in quantum computing, spintronics and memory devices. In contrast, similar features were only recently reported for spin chain oxides built up of face-sharing MnO₆ octahedra and CoO₆ trigonal prisms. We describe the huge potential of one dimensional A_1x+(Mn_2-xCo_x)O_3+δ oxides with A=Ca, Sr, Ba whose aperiodic structures can be designed by considering a mechanism of extra oxygen incorporation (EOI). We show that these oxides exhibit a crossover from a single chain magnet (SCM) to a long range order (LRO), or more exactly, to a partially disordered antiferromagnetic (PDA) behavior.
Thermoelectric (TE) materials, which allow the conversion of waste heat into clean electricity, have been the object of extensive investigations in last fifteen years. Quite a limited number of sulfides have been investigated to date in spite of the rich crystal chemistry of these materials that offers a promising route for the discovery of new physical properties. This is exemplified by the copper rich sulfides with a 3D tetrahedral conductive "Cu-S" framework. The presence of large amounts of univalent copper in these materials makes them remarkable p-type thermoelectrics. Various frameworks can be realized by mimicking the natural minerals such as stannite, bornite, colusite, germanite and stannoidite. The very recent discovery of the thermoelectric colusites Cu₂₆T₂Ge₆S₃₂ with T=Mo, W, Cr which exhibit outstanding power factors and high ZT figures of merit, illustrates the great potential of these materials.

The crystal chemistry of inorganic compounds featuring mixed anionic framework provides a broad richness from the standpoint of the structure and properties.(1-2) The solid-state chemistry of titanium-based oxide-fluoride compounds is a school case to exemplify how anions can arrange in different structural arrangements. In this presentation, we shall exemplify the structural arrangements through two examples showing how anions, particularly fluoride, can be ordered. In a first example, we will describe the structure of a cubic phase TiOF₂ from the average to the local order standpoints. Thereafter, we will describe how monovalent anions such as fluoride and hydroxide can be stabilized in an oxide framework, leading to the stabilization of cationic vacancies (3). Finally, we will present how these defects can unlock the electrochemical activity toward multivalent ions opening new avenues to develop new electrochemical devices (4).

Although primary lithium batteries have shown promising performances as a cathode, only a few works have been devoted to graphite oxyfluorides [1]. For such applications, most of the studies about covalent Graphite Interclation Compounds (GICs) mainly concern graphite oxides (GO) [2] and graphite fluorides (GF) [3-10]. Nevertheless, the rare works on oxyfluorides suggest high potentialities, such as an energy density of 1347 Wh.Kg^-1 for a sample obtained by a two-step synthesis combining fluorination and oxidation and even 2265 Wh.Kg^-1, thus exceeding graphite fluorides [11]. Fluorinated oxides were highly capacitive while oxidized fluorides have highest discharge potential despite having the same graphite precursor. Such data demonstrated that engineering the synthesis enables to modulate the properties. Different graphite oxyfluorides were synthesized via Hummer's oxidation of sub-fluorinated graphites in order to maintain sp² carbon atoms available for the oxidation, C-F bonds being non-reactive. In comparison with the graphite fluoride precursors, significant improvement of the energy density in primary lithium battery is achieved when the graphite oxyfluorides are used as cathode. When Hummer's oxidation was carried out on graphite fluoride with both the CF_0.60 composition and a homogenous dispersion of non-fluorinated regions into fluorinated lattice, oxidation focused on the remaining sp² carbon atoms and decomposed them. Defected graphite fluorides were then synthesized. The highest ever measured energy density in the primary lithium battery with fluorinated carbons as cathode, i.e. 2825 Wh.Kg^-1, was reached with this particular sample. Solid state NMR allowed the functional groups C-F, COC, COH, COOH and sp² C to be quantified in graphite oxyfluorides and fluorides and their role in electrochemical processes to be highlighted.

Li-ion batteries have dominated the energy storage device market and are widely used in portable electronic devices as well as hybrid and electric vehicles (HEV, EV). Unfortunately, the world’s limited resources of lithium and its growing prices have made it necessary to conduct intensive research aimed at improving the materials used in lithium batteries and obtaining cells with better parameters, i.e. higher energy and power densities.
In the previous work, we presented the results of electronic structure calculations performed for LixNi0.9−yCoyMn0.1O2 [1]. In this work, we expand on our previous analysis by considering the additional influence of copper atoms on electronic structure – especially with regard to the modification of density of states in the vicinity of the Fermi energy (EF). This paper discusses both practical and theoretical aspects of operation of Li-ion cells, presents the results of structural, transport and electrochemical properties of Cu-substituted cathode materials from a group of LiNi0.9-y-zCoyMn0.1CuzO2 mixed oxides, supported by electronic structure calculations performed using KKR-CPA method (Korringa-Kohn-Rostoker method with the coherent potential approximation (CPA) to account for chemical disorder [2, 3]). The presented data show that copper has a beneficial effect on electronic transport properties, lithium diffusion and cathodes performance. Battery on the base on the developed LiNi0.88-yCoyMn0.1Cu0.02O2 cathode materials is characterized by high voltage, high capacity and high rate capability, which guarantees high energy and power densities.
The correlation between the results of electronic structure calculations, the transport properties and electrochemical behaviour of LixNi0.58Co0.3Mn0.1Cu0.02O2-δ cathode is shown.
The project was funded by the National Science Centre Poland (NCN) under the “OPUS 12” programme on the basis of the decision number UMO- 2016/23/B/ST8/00199 and AGH University research grant no. 16.16.210.476. This work was carried out using infrastructure of the Laboratory of Materials for Renewable Energy Conversion and Storage, Centre of Energy AGH.

Diffuse orbitals and large magnetic anisotropy resulting from strong spin-orbit coupling make complexes with central ions from the 4d and 5d series interesting modules for magnetic materials [1]. The vast majority of molecule-based magnetic materials encompassing those elements utilize cyanide bridging. The common linearity of {M–CN–M} motifs is paralleled in fluoride-bridged systems, which thereby also proffers the desired synthetic handle in the design of new materials. When using simple [MF₆]^n– complexes as building blocks for complex architectures, the main obstacle is their common inherent lability outside hydrofluoric acid solutions, towards, for example, hydrolysis. This tendency is strongly diminished for several 4d and 5d [MF₆]^2– complexes and we herein present the use of [MF₆]^2– (M = Zr, Re, Ir, Os,…) anions, prepared by various fluorination routes, as modules for molecular magnetic systems of various dimensionality [2]. We also discuss the chemistry and potential of related 5f systems such as [UF₆]^2– [3]. The ability of fluoride to mediate significant exchange interactions dwarfs the coupling present in related cyanide-bridged systems. Conclusively, our results reveal structurally simple, robust and strongly anisotropic [MF₆]^2– complexes of the heavier transition elements to be unique and versatile building blocks for novel types of (magnetically interesting) molecular systems.

The main purpose of this study was to identify some physical and chemical characteristics of drinking water in some villages in the vicinity of the "Trepca" mine. A part of Kosovo’s economic development has primarily been oriented towards the development of the mining sector for the sake of large natural and underground resources.
Exploitation technologies as well as processing technology were not at the level as they are nowadays. Consequently, many problems have also been inherited in the field of the environment.
Here, first of all, the environmental impact of industrial wastes, industrial plants, mining landfills, chemical landfills and the agriculture sector should be highlighted.
The study consists of physical-chemical bacteriological analysis and determination of heavy metals in underground waters in some villages around the "Trepeca” mine. Based on these analyzes, the possibility of using sources of this water as drinking water was tested. Water is a substance with a number of unique attributes that acknowledge the existence of the living world in general, as well as the existence of the industry.
Drinking water acidity is emphasized in these villages, due to the strong impact of the "Trepca" Mines, and of course there is no branch of the industry that does not use this water.
Physico-chemical and bacteriological analyzes were carried out at the National Institute of Public Health in Mitrovica, whereas the determination of heavy metals was done at the Mining Laboratory with Flotation in the "Trepeca" in Mitrovica.
Qualitative assessment consisted in analyzing key indicators as well as comparing them with drinking water standards according to the Standards of Direc. 98/83 EC, WHOs.
The main purpose was to search through physical-chemical parameters to determine the quality of drinking water in these villages and highlight the determination of acidity. I think this will serve the first point of the local population living in the vicinity of the source. I also believe that the results will be used by state institutions as a basis for further research.

The architecture of Solid Oxide fuel Cells/Solid Oxide Electrolysis Cells (SOFC/SOEC) has changed with time, mainly with regard to the operating temperature. Decreasing this temperature from 950°C down to 600°C required not only to decrease the ohmic drop of the electrolyte, but also to enhance the electrode performances. If the classical hydrogen electrode remains the efficient Ni/electrolyte cermet, the oxygen electrode has to be significantly improved with the aim to reduce the overpotential.
Early oxygen electrodes in ESC (Electrolyte Supported Cell operating at T > 900°C) were made of a screen printed YSZ (Yttria Stabilized Zirconia) - LSM (Lanthanum Strontium Manganite) composite. Later on, these composite electrodes were replaced in ASC (Anode Supported Cells operating at about 750°C) by appropriate unique oxides showing mixed ionic and electronic conduction, such as the Lanthanum Strontium Ferro-Cobaltite (LSFC) [1].
More recently, we have shown that lanthanide nickelates Ln₂NiO_4+δ (Ln = La, Pr or Nd) exhibit very good ionic diffusivity of oxides ions as well as oxygen exchange properties leading to outstanding electrochemical properties as oxygen electrode materials [1-2].
Improvement of the cell performance was also achieved thanks to the addition of a thin interlayer ( = 2-3 µm) in between the electrolyte and the oxygen electrode; it mainly plays the role of a barrier against cation diffusion due to the reactivity of these materials with each other [3].
In the last generation of cells, the so called MSC (Metal Supported Cell operating at 600-700°C), has to allow imagination of new ways to make the oxygen electrodes. This has to be done with regard to the presence of metal which can be oxidized at temperatures higher than 900°C during the fabrication process. The infiltration technique has proven to be a promising route to make highly efficient electrodes [4]. The electrocatalyst is infiltrated in a porous skeleton (Gadolinia doped Ceria, GDC) sintered on the YSZ electrolyte, then fired at low temperatures (T = 600-800°C), leading to the formation of nanoparticles showing high electrocatalytic properties [5].
A review of all these issues is presented.

Fluoride glasses have been an attractive material for thirty years in shorter optical devices with applications lying in the visible and mid IR spectral range due to their low phonon energy (~500-600 cm-1). In this review, the information on glass-forming fluoride systems is presented, and the main methods for synthesizing glasses on the basis of fluorides of the metals of Groups IIV, their physicochemical properties, techniques for producing fibers, areas of application, and the techniques for purifying them from undesired impurities are discussed. Modern materials science studies in the area of fluoride glasses are aimed at searching for glasses activated with rare-earth elements (REEs) or transition elements with a broad IR transmission range and high optical homogeneity. This is in the purpose of creating efficient active optical media in a wide spectral range [1-3], as well as creating converters of IR radiation into the visible range for enhancing the efficiency of solar cells[4]. At present, the fluoride phosphors activated by Mn⁴⁺ ions, which emit a narrow-band spectrum in the red region and absorb strong optical radiation in the blue spectral region, are considered to be the most promising light converters. The modified fluorozirconate glasses (ZBLAN) doped with BaCl₂, BaBr₂ MnO₂ were synthesized and their luminescence and EPR spectra were measured. As a result, we synthesized a new phosphor based on fluorozirconate glass doped with manganese ions, in which a long-wavelength shift of the manganese green luminescence band into the red region (610 nm) has been found.

Fluoride materials attract much interest as cathode materials for secondary batteries because of the high electronegativity of the fluorine atom, affording higher potentials than oxide analogues.[1] In this context, iron trifluoride FeF₃ has been intensively used due to its straightforward elaboration in relatively mild synthesis conditions; iron is considered as environmentally friendly. In the case of an intercalation mechanism, the theoretical capacity for FeF₃ (1Li⁺ per Fe) reaches 237 mAh.g^-1, a value higher than that obtained for the LiFePO₄ commercial material (170 mAh.g^-1). With the conversion reaction, this capacity can even reach 712 mAh.g^-1, implying a reduction of the trivalent iron. Despite good electrochemical performances in capacity and redox potential, the high ionicity of M-F bonds induces a large band-gap resulting in poor electronic conductivity. A recent study shows that the dehydration of HTB-FeF_2.2(OH)_0.8.0.33H₂O (Hexagonal Tungsten Bronze) leads to a lacunar oxyfluoride with anionic vacancies, thus having a positive effect on electrochemical performances (cyclability and capacity).[3]
In this work, mixed fluorides M^IIM^III₂F₈(H₂O)₂, M^IIM^IIIF₅(H₂O)₂ weberites, and their corresponding dehydrated intermediate phases were considered for their electrochemical activity (M = V, Mn, Fe, Co, Ni, Cu).[4] The hydrated phases were synthesized by a solvothermal route, eventually assisted by microwave heating and characterized by X-ray diffraction (XRD) and ⁵⁷Fe Mössbauer spectrometry. The formulations and structural features of the intermediates stabilized after heating treatments under different atmospheres were determined by combining thermal analysis, powder XRD, MET, pair distribution function, IRTF and Mössbauer spectrometry. Finally, the electrochemical performances of all-synthesized fluoride materials demonstrate that several dehydrated phases could be a good alternative as positive electrode materials with capacities at the first discharge up to 306 mAh.g^-1.[4]

Vitreous materials based on fluorides or on chalcogen elements (S, Se, Te) show large transparency windows in the infrared. Indeed, fluoride glasses are transparent from the UV to 7 micrometers in the infrared, while chalcogenides can be transparent from the visible up to 12-15 micrometers, depending on their compositions [1]. This is due to the lower phonon energies of non-oxide glasses, which are also responsible for enhanced luminescence of rare-earth ions embedded in such matrices, as compared to oxides. Thus, these glasses allow light emission at wavelengths not accessible with silica. In addition, chalcogenide glasses contain large polarisable atoms and external lone electron pairs that induce exceptional non-linear properties. The non-linear properties of chalcogenides can be 100 to 1000 times as high as the non-linearity of silica.
As far as shaping is concerned, specific fluoride and chalcogenide glasses can be obtained in the form of optical fibers. Applications are directly related to the combination of unique optical properties and shaping abilities.
The presentation deals with an overview of the synthesis and properties of non-oxide glasses, completed by the latest results, in terms of applications, in two fields of technological or societal importance. The first one is the generation of supercontinuum of infrared light by using fluoride and/or chalcogenide optical fibers [2-4]. The second one is the detection of green-house-effect gases like CO₂ by using optical sensors based on rare-earth-doped chalcogenide fibers [5].

Oxygen ions are incorporated in and released from transition-metal oxides when the valence states of the transition-metal ions change [1]. In topotactic changes of perovskite-structure oxides like SrFe²⁺O₂ - SrFe³⁺O_2.5 - SrFe⁴⁺O₃, we found that the oxygen incorporation and release behaviors are strongly influenced by the structural factors. The A-site disordered perovskite (La_1/3Ca_2/3)FeO₃ with unusually high valance Fe^3.67+ releases oxygen gradually above 500°C, whereas the A-site-layer-ordered perovskite LaCa₂Fe₃O₉ with the identical chemical composition of (La_1/3Ca_2/3)FeO₃ readily releases oxygen around 400°C [2,3]. From the B-site-layer-ordered double perovskite Ca₂FeMnO₆ with Mn⁴⁺ and unusual high valence Fe⁴⁺, oxygen is released only form the two-dimensional Fe-O layers according to the successive changes of Ca₂Fe⁴⁺Mn⁴⁺O₆ - Ca₂Fe^3.5+Mn⁴⁺O_5.75 - Ca₂Fe³⁺Mn⁴⁺O_5.5. The B-site-disordered Ca₂(FeMn)O₆, on the other hand, oxygen appears to be released at about 390°C by a single change of Ca₂(Fe⁴⁺Mn⁴⁺)O₆ - Ca₂(Fe³⁺Mn⁴⁺)O_5.5 [4,5]. Thus, the oxygen release behaviors differ depending on both A-site and B-site cation order. An important point for the behaviors of oxides with unusually high valence cations like Fe⁴⁺ is that the incorporation and the release of oxygen can occur at much lower temperatures than those with typical valence transition-metal ions. We will discuss the details of such behaviors from temperature-dependent structure analysis.

Around various transition metals (Ti and Fe), p-block elements (In) or rare-earths (Ce) associated to at least two different anions (F, O, S), original networks can be designed associated to specific optical and electronic properties and various elemental rules can be established. First, the Ti-based oxy-hydroxy-fluorides with the HTB network were prepared by the solvothermal route and the original structure has been determined. The optical band gap can be tuned in UV range as a function of the O/F atomic ratio, leading to the design of UV-absorbers with low refractive index. V or Mo partial substitution contributes to shift the band gap in the visible range. The heat-treatment of Fe fluoride trihydrate up to T=350°C under Ar leads to stability for the first time where Fe oxy-fluoride has anionic vacancies in the HTB network. The formation of structural units containing 5-fold coordinated Fe atoms in this HTB network leads to a strong reduction of the optical band gap from 4.05 eV in FeF₃, 3H₂O to 2.05 eV in the Fe oxyfluoride thanks to the occurrence of 2p-oxygen states on the top of the valence band. The reaction between anhydrous In fluoride and water at 400°C under Ar (InF₃ + H₂O → InOF + 2HF) leads to In oxyfluoride which adopt a derived fluorite-type structure with O/F ordering. InOF can be considered as a transparent conductive oxyfluoride with band gap energy of 3.7 eV. It can also be considered as a smaller work function compared to In2O₃ due to the destabilization of conduction band thanks to the structural features of InOF. With these unusual optical and electronic properties, numerous In-based oxyfluorides can be designed. The reduction under H₂ at 700°C of Ce fluoro-carbonate CeFCO₃ leads to the preparation of pure CeOF with O/F ordering which exhibits a blue-grey coloration. The H₂S treatment at T=700°C-800°C of CeIII fluoride, oxyfluoride or fluorocarbonate, allows obtainment of Ce fluoro-sulfide CeSF which adopts a 2D network like CeOF, derived from the fluorite-type structure. The band gap strongly varies from UV in CeOF to visible range in CeSF with around 2eV associated to a red coloration. The key features of mixed anion systems will be highlighted from the analysis of reactivity, structure and local environments to tune the band gap.

Hydrotalcite-based nanomaterials have gained considerable interest by academic and industrial researchers due to their properties in several industrial domains such as in medicine, the pharmaceutical industry, catalysis, electrochemistry, and in polymerization reactions [1, 3]. Catalytic properties can especially be tuned due their double lamellar sheet structure charged positively where divalent M²⁺ and trivalent M³⁺metals are located.
In the present work, hydrotalcite-derived samples based on Ni and Co (NiMgAl, CoMgAl and NiCoMgAl) were prepared by low saturation coprecipitation at constant basic pH (pH = 11). The precursors were calcined at 450°C (4°C/min) for 6 hours. After that, the temperature was reduced to 700°C (4°C/min) during 1 hour. All obtained solids (none calcined, calcined and reduced) were characterized by several physico-chemical analysis methods (DRX, SAA, FTIR, SEM, MET, RTP, ATG/ATD and BET).The catalysts obtained were tested in dry reforming of methane (DRM), considered as promising for the production of syngas (H₂ + CO) in order to reduce the footprint of greenhouses gas (CH₄, CO₂), which is one of the keys of the climate transition. Catalytic testing of DRM for the series of the catalysts (NiMgAl-HTc-R, CoMgAl-HTc-R and NiCoMgAl-HTc-R) was carried out at 700°C (4°C/min) for 20 hours.
The catalytic performances of examined solids showed the following sequence:
NiMgAl-HTc-R >NiCoMgAl-HTc-R >>>>CoMgAl-HTc-R.
NiMgAl-HTc-R was found to exhibit the best catalytic activity, selectivity with the highest resistance to the carbon poisoning and was ascribed to the good textural and structural features presented by NiMgAl-HTc-R such as high surface area, strong basic character and well dispersion of the active phase.

This presentation examines the current status of renewables in the world. The presentation starts with some facts about the climate change, global warming and the effects of human activities such as the burning of fossil fuels on the climate problem. It then examines the current status of conventional resources of energy such as oil, coal, natural gas and their reserves based on current consumption, and known resources. This is followed by a general outline of the status of renewables in the world, which includes the shares with respect to conventional fuel use for electricity and power and jobs created. Then the basic forms of renewables are examined in some detail, which include solar and thermal applications, both for low and high temperatures, photovoltaics, hydro power, onshore and offshore wind energy systems and biomass/biofuels. In all these, the basic technology is presented followed by the current status as well as the prospects of the technology and new research findings. Finally, some basic facts about the Renewable Energy Journal in which the speaker is the Editor in Chief are presented.

Among the factors controlling the critical temperature (Tc) in the high temperature superconducting cuprates (HTSC), the hole-doping level is one of the most crucial ones. In fact, superconductivity is suggested to be restricted to a “universal” hole doping level 1 psh comprised between ~0.06 and 0.31 holes per copper plane. While the complex charge-spin-lattice interplay in the underdoped regime (i.e. at ppopt) remains less explored and perceived as simpler, Fermi-liquid behaved. Recent results, however, are highlighting the potential of this overdoped region in the understanding of the condensation mechanism.
In searching for overdoped systems, the so-called M-1212 phases resulting from partial or total substitution of copper in the Charge Reservoir Layer by other transition metals (TM) are suitable candidates. This is because they allow the total oxygen content to be widely modified with respect to the YSCO parent compound. This is particularly true for high valent TM, as the Mo(V-VI) and Fe(III-IV) cations in the Mo_0.3Cu_0.7Sr₂RECu₂Oy₃ and FeSr₂YCu₂Oy phases, in which the oxygen content can be raised to y > 7, above the YBCO limit. This leads to very highly doped CuO₂ planes, outside the Tc-psh paradigm.
To shed light to the superconducting properties of these substantially overdoped (Mo & Fe)-1212 systems, we have varied both the oxidation degree and the RE size, looking at the effect of the crystal structure on Tc. We specifically focus on the connection between the atomic arrangement within the unit cell and the hole distribution. To that end, we have performed a joint structural-electronic characterization by means of NPD, ARM and EELS spectroscopy of ozone4 and high-pressure oxidized phases.
We have observed that these materials, which are outside the paradigm, can be superconducting. Due to the Tc increasing with a whole doping level almost double than the above limit. We have also established the upmost importance of order-disorder in both the cation and anion sublattices.

Sodium ion Batteries (SIBs) offer a strong alternative to existing battery technologies, particularly in the field of stationary storage due to their potentially low cost, and natural abundant precursors.[1,2] One key component of an SIB is the cathode, the nature of which is critical to its performance. Sodium layered oxides (SLOs), with the stoichiometry NaT_MO₂ (T_M = one or more transition metals, e.g. Mn, Fe, Co, Ni, etc.), are a promising family of cathode materials due to their excellent electrochemical properties, structural simplicity, and tuneable stoichiometries.[3] SLOs, consisting of repeating sheets of T_MO₆ layers with Na ions located between, are classified by a letter and number (e.g. O3-, P2-, etc.) where the letter indicates the Na is located (O: octahedral, P: prismatic) and the number indicates the number of interlayers that are surrounding.[4]
Performance of these materials is frequently governed by their structure, and in this work we will highlight the importance of taking this into consideration. For example, while Manganese-rich layered oxides are particularly attractive due to their combination of low cost and low toxicity, their performances are often hindered by the effect of Jahn-Teller distortion (resulting from the presence of Mn³⁺).[5] We will not only discuss this in detail, but also highlight mitigation strategies, such as doping with electrochemically active (e.g. Fe) and inactive (e.g. Mg, Ti) elements, or synergetic P2/O3 combination effects.[5-8]
We will also examine the importance of Na-ion conductivity, determined through the use of combined electrochemical techniques and solid-state NMR spectroscopy, and show how the mobility of Na ions is related to the different local environments of Na ions (i.e. O- or P- phase) and diffusion pathways.[9] This way, we will not only show a thorough knowledge where SLO structure is key to understanding their behaviour, but also how to link this to the key descriptors for the cathode material's electrochemical performance.

Spinodal decomposition is a ubiquitous phenomenon leading to phase separation from a uniform solution. We show that spinodal decomposition occurs in a unique combination of two rutile compounds of TiO₂ and VO₂ [1-3], which are chemically and physically distinguished from each other: TiO₂ is a wide-gap insulator with photocatalytic activities, and VO₂ is assumed to be a strongly correlated electron system which exhibits a dramatic metal-insulator transition at 342 K. Spinodal decomposition takes place below 830 K at a critical composition of 34 mol% Ti. It generates a unidirectional composition modulation along the c axis with a wavelength of approximately 6 nm, and finally results in the formation of self-assembled lamella structures made up of Ti-rich and V-rich layers stacked alternately with 30-50 nm wavelengths. A metal-insulator transition is not observed in quenched solid solutions with intermediate compositions, but emerges in the thin V-rich layers as the result of phase separation. Interestingly, the metal-insulator transition remains as sharp as in pure VO₂ even in such thin layers and takes place at significantly reduced temperatures of 310-340 K. This is probably due to a large misfit strain induced by lattice matching at the coherent interface.

Fluoropolymers are valuable materials endowed with outstanding properties that allow them to be involved in many High-Tech applications [1]. This presentation aims at reporting how the design of functional fluoropolymers may influence the properties and applications. Actually, 2-trifluoromethacrylic acid (MAF) is a versatile building block for the synthesis of new functional monomers. [2] It can be homopolymerized by anionic initiation [2-3] but fails in the presence of any radical systems. However, its radical copolymerization with vinylidene fluoride (VDF) has been successful. This presentation reports overall strategies to synthesize novel functional 2-trifluoromethacrylate monomers and macromonomers, as well as their radical copolymerization with VDF, leading to various materials such as higher thermal stable thermoplastics,[4] polymer gel electrolytes for Lithium ion batteries,[5-7] and anticorrosion [8] and adhesive hybrid coatings [9] (Figure 1).
Figure 1 shows the overall strategies to synthesize novel functional 2-trifluoromethyl monomers from 2-trifluoromethacrylic acid (MAF) and their radical copolymerization with VDF (left). The figure also shows steel plates coated with poly(VDF-co-MAF Phosphonate) copolymer at the beginning of the experiment (A), after 1 h (B), and after 18 h (C). (D): uncoated steel plate used as reference sample after 1 h (right).
Tosoh FineChem Corporation (Shunan, Japan) is acknowledged for suppling MAF monomers.

Fluorinated materials have unique and extraordinary properties and that lead to their development and usage in all manufacturing and service sectors. The use of fluorine is no longer confined to traditional glass, metal, nuclear, fluoropolymer, pharmaceutical or agrochemical industries. New and challenging requirements next generation technologies of energy conversion, optoelectronics, semiconductors and electrical vehicle manufacturing industries have driven technological development of more advanced fluorinated materials.
Fluorine is everywhere in our daily lives from our comfortable air-conditioned rooms, offices, and kitchens to cars and hospitals. The exponential growth in all manufacturing sectors and fluorochemical industries and increased consumption of fluorinated products have resulted in depletion occurring naturally, but this limits the main resource, fluorspar. This has provided opportunities to researchers to think and work on conservation and recycling and focus on the sustainable development of the fluorochemical industry in general.
ln this paper, the important role of fluorine materials in our daily lives shall be summarized. Help from Contributions of Advance Research Chemicals, lnc. , including production of inorganic fluorides for the semiconductor industry and energy conversion will be briefly described. Actions taken by the scientific community and industry on sustainable development will also be presented.

Quantum chemical calculations (semi-empirical and non-empirical) are used to design new phosphors with Eu ²⁺ for white Light Emitting Diodes (LEDs) used for artificial lighting. This is of ultimate importance as the quest for optimal white LEDs is still relevant. The model which uses Density Functional Theory is based on an effective Hamiltonian that includes electrostatic, spin-orbit and ligand field contributions. From these calculations, the multiple energy levels arising from the ground 4f7 and excited 4f65d1 electron configurations of Eu²⁺ in their chemical environment are obtained. The results are in good agreement with the experimental investigations, validating the usefulness of theoretical modelling to understand and characterize the luminescence spectra of phosphors with Eu²⁺. [1,2] The luminescence properties of the new phosphor BaSnSi₃O₉:Eu²⁺ have been theoretically predicted and then experimentally verified. [3]

Pigments can be classified into two families: the organic ones, related to carbon chemistry and the inorganic ones; both of them have advantages and drawbacks. The variety of colours available in organic pigments is greater and these colours are more resistant to exposure to sunlight or chemicals. Organic pigments, however, are easier to stabilize and disperse and they exhibit brighter colours.
In order to combine the advantages of both organic and inorganic types, UGIEL - a spin-out company from the ICMCB/CNRS laboratory - developed and patented green chemistry routes to graft and texture gold onto a wide range of support with nanometric precision. This results in a new generation of fully inorganic or hybrid organic-inorganic pigments with a wide range of colourful appearances and functionalities, relying on the inalterability and the biocompatibility of gold.
First, a brief historical overview of nanosized gold and silver pigments will be given [1]. Then, microstructural features of UGIEL pigments will be described and related to their colourful appearances and applications.