ORALS

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

15:55: [AdvancedMaterialsTuePM209] OS
Ruddlesden-Popper-type Nd2-xNi0.75Cu0.2M0.05O4±δ (x = 0 and 0.1; M = Ga, Sc and In) layered oxides as candidate materials for MIEC-type ceramic membranes
Konrad Swierczek¹ ; Anna Niemczyk¹ ; Anna Olszewska¹ ; Zijia Zhang² ; Hailei Zhao² ; Kacper Cichy³ ; ¹AGH University of Science and Technology, Faculty of Energy and Fuels, Krakow, Poland; ²University of Science and Technology Beijing, School of Materials Science and Engineering, Beijing, China; ³AGH University of Science and Technology, Krakow, Poland;
Paper Id: 138 [Abstract]

Ceramic membranes, due to their high permeability, ability to work in the aggressive environment, including high temperature and high pressure, chemical and mechanical stability seem to be promising substitution compared to the commonly used polymeric membranes. Despite their higher investment cost, in relation to the organic membranes, ceramic gas separators are more economically favourable in long term perspective (slower degradation) [1,2] Similarly to Solid Oxide Fuel Cells (SOFCs) and Solid Oxide Electrolyzer Cells (SOECs), membrane technologies are considered as one of the basic solution in so-called Grand Energy Transmission [3-5]. Ruddlesden-Popper-type (RP) oxides usually possess mixed ionic-electronic conductivity, which is a crucial requirement for the effectively-working ceramic membranes. Ionic transport in the considered group of materials might be realized by the vacancy mechanism (in the perovskite-type layer) or by rather unusual interstitial mechanism employing interstitial oxygen. In this work RP Nd_2-xNi_0.75Cu_0.2M_0.05O_4±δ (x = 0 and 0.1; M = Ga, Sc and In) oxides were obtained by a sol-gel route and characterized concerning phase composition and crystal structure. Among the materials, Nd_2-xNi_0.75Cu_0.2Ga_0.05O_4±δ (x = 0; 0.1) were selected, with systematic characterization of the crystal structure at high temperatures, oxygen content, as well as transport properties measured. It is shown that the Nd-site deficiency causes decrease of the oxygen content, which at high temperatures leads to a change of the dominant type of defects from the oxygen interstitials to the vacancies. Importantly, both examined Ga-containing materials exhibit full chemical stability in CO₂ atmosphere, which makes them good candidates for air separation technology. Ceramic membranes manufactured using Nd₂Ni_0.75Cu_0.2Ga_0.05O_4±δ and Nd_1.9Ni_0.75Cu_0.2Ga_0.05O_4±δ fine powders allowed to obtain very high oxygen fluxes equal to 0.69 mL cm^-2 min^-1 and 0.78 mL cm^-2 min^-1 at ca. 880 °C, respectively for 0.9 mm thick pellets. Moreover, it is shown for Nd₂Ni_0.75Cu_0.2Ga_0.05O_4±δ-based pellet that infiltration of the grains with the higher order RP oxide (e.g. La₄Ni₃O₁₀) combined with reduced thickness of the membrane allows to maximize oxygen flux values, with one of the highest reported oxygen fluxes measured for CO₂-stable RP-based ceramic membrane, i.e. 0.94 mL cm^-2 min^-1 at ca. 880 °C for 0.6 mm thick dense membrane.

References:
[1] J. Garcia-Fayos, J. M. Serra, M. W. J. Luiten-Olieman and W. A. Meulenberg, Gas separation ceramic membranes. Advanced Ceramics for Energy Conversion and Storage, Elsevier 2020
[2] H. A. Meinema, R. W. J. Dirrix, H. W. Brinkman, R. A. Terpstra, J. Jekerle and P. H. Kösters, InterCeram Int. Ceram. Rev., 2005, 54, 86-91
[3] A. Fargere, B. Kolodziejczyk, J. Carton, L. Lapeña Martinez, A. Pica Téllez, C. Karaca, Y. Chae and L. Fuselli, Hydrogen an enabler of the Grand Transition, 2018
[4] I. Staffell, D. Scamman, A. Velazquez Abad, P. Balcombe, P. E. Dodds, P. Ekins, N. Shah and K. R. Ward, Energy Environ. Sci., 2019, 12, 463-491
[5] M. Gotz, J. Lefebvre, F. Mors, A. McDaniem Koch, S. Bajohr, R. Reimert and T. Kolb, Renewable Energy, 2016, 85, 1371-1390

SESSION: AdvancedMaterialsTuePM3-R10	6th Intl. Symp. on New & Advanced Materials & Technologies for Energy, Environment, Health & Sustainable Development
Tue. 29 Nov. 2022 / Room: Saitong
Session Chairs: Keyun Li; Session Monitor: TBA

18:15: [AdvancedMaterialsTuePM314] OS
Cu-based perovskite-type oxides as air electrodes for Solid Oxide Cells
Keyun Li¹ ; Anna Niemczyk² ; Konrad Swierczek¹ ; Yevgeniy Naumovich² ; Jakub Kupecki² ; Anna Olszewska¹ ; Kun Zheng³ ; Bogdan Dabrowski⁴ ; ¹AGH University of Science and Technology, Faculty of Energy and Fuels, Krakow, Poland; ²Institute of Power Engineering - Research Institute, Warsaw, Poland; ³AGH University of Science and Technology, Krakow, Poland; ⁴Polish Academy of Sciences, Institute of Physics, Warsaw, Poland;
Paper Id: 189 [Abstract]

Reversible solid oxide cells (rSOC), which can act as an electricity and heat generator converting the chemical energy of fuel, as well as an electrolyzer generating hydrogen in the reversed mode operation (exploiting surplus electrical energy), are considered as unique energy conversion devices [1, 2]. Their application seems to be especially suitable in the dispersed power systems, possibly enabling to address unresolved problems of power grid balancing. For their effective work, electrochemical reactions taking place at the electrodes must be sufficiently fast and reversible, which requires for the electrode materials to possess a number of specific properties, including high electrocatalytic activity and suitable thermomechanical properties. Nowadays, Co-based perovskite-type oxides are most widely-used compounds for the air electrodes, however, political and environmental factors indicate a need to replace Co with other 3d transition metal elements. In various proposed materials Co was successfully replaced by e.g. Fe or Mn [3, 4], there are not so many papers available on the possible introduction of Cu. However, several already published works show that Cu-based perovskite-type oxides can work effectively when used in the SOCs [5]. In this work, different issues related to the development of Cu-containing air electrode compounds are discussed, focused on the proposed RE_1-xA_xCu_xO_3-δ (RE: selected rare-earth elements, A: selected alkaline-earth metals) perovskite-type oxides. The considered materials were explored concerning their crystal lattice, thermal expansion behavior, oxygen content, as well as mixed ionic-electronic transport properties. For the exemplary La_1.5Ba_1.5Cu₃O_7±δ, two synthesis routes, sol-gel and solid-state, allowed to successfully obtain pure material. The synthesized perovskite exhibits favorable physicochemical characteristics, including layered crystal structure, and mixed Cu²⁺/Cu³⁺ states, which can be linked with the enhanced activity of the oxygen reduction/oxygen evolution reactions. The stabilized layered crystal structure with P4/mmm symmetry is beneficial to the enhanced electrical conductivity, at the same time allowing to keep moderate thermal expansion coefficient (ca. 15.5·10^-6 K^-1 at 50-900 °C). Additionally, laboratory-scale button-type cells (in the electrolyte-supported and the anode-supported configurations) could be manufactured and tested in terms of their electrochemical performance, confirming applicability of the developed material.

References:
[1] A. Arsalis, Renew Sustain Energy Rev. 105 (2019) 391-414
[2] U.M. Damo et al., Energy 168 (2019) 235-246
[3] F. Tietz et al., J. Power Sources 156, 20–22 (2006).
[4] A. Olszewska et al., J. Mater. Chem. A 6(27) (2018) 13271-13285
[5] A. Niemczyk et al., J. Mater. Chem. A 7(48) (2019) 27403-27416