ORALS

SESSION: AdvancedMaterialsTuePM1-R10	6th Intl. Symp. on New & Advanced Materials & Technologies for Energy, Environment, Health & Sustainable Development
Tue. 29 Nov. 2022 / Room: Saitong
Session Chairs: Igor Konyashin; Session Monitor: TBA

14:00: [AdvancedMaterialsTuePM105] OS
Effects of Size and Morphology of Antimony Working as Anodes for Na-ion Batteries
Justyna Płotek¹ ; Andrzej Kulka² ; Janina Molenda³ ; ¹AGH University of Science and Technology, Kraków, Poland; ²AGH University of Science and Technology, Cracow, Poland; ³AGH University of Science and Technology, Kraków, Kraków, Poland;
Paper Id: 198 [Abstract]

The energy storage systems market was dominated by Li-ion batteries (LIBs) almost as soon as they were commercialized in 1991. Demand for this technology is forecasted to grow further, especially with the growing use of renewable energy sources, which need reliable, high efficiency and high capacity energy storage system [1]. However, limited lithium abundance in the earth’s crust intensifies the search for an alternative technology. Na-ion batteries is a proposed solution, because of similar to the LIBs operation mechanism and abundance of sodium on earth. Nevertheless, the lack of appropriate anode materials is one of the major hindrances in the development of that technology. The most common anode material for Li-ion batteries – graphite, intercalate Na⁺ ions only in a limited range. Researchers' attention is drawn to elements from the 14 and 15 groups of the periodic table, working in Na-ions via alloying materials. Among them, antimony stands out because of its high electrical conductivity (2,56·10⁶ S m^-1) and also the high theoretical capacity of 660 mAh g^-1 [2]. However, the volume change related to alloying/dealloying process is approximate 293% which causes severe microstructure degradation and as a result impeded reaction kinetics and poor cycling stability [3]. The prospective strategy to overcome obstacles is synthesizing the nano-sized Sb. The aim is to elucidate the relationship between physicochemical properties, size, and morphology of Sb-particles. The work presents a comparison of structural and electrochemical properties of nano-sized antimony synthesized via hydrothermal reaction [4] and bulk micrometric Sb. The X-ray diffraction and scanning electron microscopy were conducted to specify the structural properties of materials. The electrochemical properties of the materials were verified by means of the standard charge/discharge cycles, rate capability tests, XRD in situ measurements, CV voltammetry, and electrochemical impedance spectroscopy. The voltage profiles confirm that during the alloying the Na₃Sb phase was formatted. The nanosized materials decreased stress-strain and as a result, improved cycle stability of cells.

References:
[1] J. Y. Hwang, S. T. Myung, and Y. K. Sun, Chem. Soc. Rev., 46 (2017) 3529–3614.
[2] H. Tan, D. Chen, X. Rui, and Y. Yu, Adv. Funct. Mater., 29 (2019) 1808745.
[3] T. Ramireddy, N. Sharma, T. Xing, Y. Chen, J. Leforestier, and A. M. Glushenkov, ACS Appl. Mater. Interfaces, 8 (2016) 30152–30164.
[4] R. Li et al., Nanoscale Res. Lett., 11 (2016) 486.

SESSION: AdvancedMaterialsTuePM2-R10	6th Intl. Symp. on New & Advanced Materials & Technologies for Energy, Environment, Health & Sustainable Development
Tue. 29 Nov. 2022 / Room: Saitong
Session Chairs: Inmaculada Ortiz; Session Monitor: TBA

17:10: [AdvancedMaterialsTuePM212] OS
From simple alkaline oxides to high entropy transition metals oxides - applications in electrochemical energy storage
Janina Molenda¹ ; ¹AGH University of Science and Technology, Kraków, Kraków, Poland;
Paper Id: 139 [Abstract]

The author of this work based on her own investigations of LixMO2 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 LixCoO2, LixNi1-y-zCoyCuzMn0.1O2 and NaxCoO2-y cathode materials and explains of apparently different character of the discharge/charge curve in those systems. Comprehensive experimental studies of physicochemical properties of LixNi1-y-zCoyCuzMn0.1O2, NaxCoO2-y and NaNi1/5Co1/5Fe1/5Mn1/5Ti1/5O2 cathode materials (XRD, electrical conductivity, thermoelectric power) are supported by electronic structure calculations performed using the Korringa-Kohn-Rostoker method 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 reduction of the gap and even to the pseudogap. The battery on the base of the developed high entropy oxides NaNi1/5Co1/5Fe1/5Mn1/5Ti1/5O2 cathode materials are characterized by high potential, high capacity and high rate capability guaranteeing high energy and power densities. Acknowledgements This work was funded by the National Science Centre Poland (NCN) under the “OPUS 17 programme on the basis of the decision number 2019/33/B/ST8/00196.

References:
J.Molenda, A.Milewska, W. Zajac, M.Rybski, J. Tobola, Phys. Chem. Phys. Chem. 19, (2017) 5697