High electrolysis performance of the SOEC cathode by creating oxygen vacancies to regulate the adsorption energy

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2024-10, Vol.12 (42), p.28911-28918
• Main Authors: Du, Yongqian, Zhao, Longyan, Xiao, Yanzhi, Kong, Jiangrong, Liu, Peng, Yang, Xianfeng, Zhou, Tao
• Format: Article
• Language: English
• Subjects: Carbon dioxide; Carbon dioxide emissions; Cathodes; Chemical reactions; Chemical reduction; Copper; Density functional theory; Electrochemical analysis; Electrochemistry; Electrode materials; Electrolysis; Emissions control; Heterostructures; Metal oxides; Nanoparticles; Oxygen; Performance degradation; Reduction (electrolytic)
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/d4ta04915b

Solid oxide electrolysis cell (SOEC), as an attractive means of CO 2 emission reduction, possesses the advantages of high efficiency, greenness and flexibility. However, the catalytic performance of cathode materials currently applied to direct CO 2 electrolysis needs to be further improved, which limits its wide application. In this study, a new strategy of using Cu nanoparticles to decorate the Sr 1.9 Fe 1.3 Cu 0.2 Mo 0.4 Ti 0.1 O 6− δ -Gd 0.2 Ce 0.8 O 1.9 (Cu@SFCMT-GDC) skeleton to improve the electrolysis performance was proposed. Through the in situ exsolution of Cu nanoparticles, rich metal-oxide heterostructures were constructed, which effectively increased the concentration of oxygen vacancies and thus promoted the electroreduction process of CO 2 . At 800 °C and 1.8 V, the maximum electrolytic current density of the cell with Cu@SFCMT-GDC as the cathode reached 1.86 A cm −1 . After 210 h of continuous operation, the Cu@SFCMT-GDC did not show any performance degradation. Cu@SFCMT-GDC exhibited outstanding electrochemical performance and durability. Density functional theory (DFT) calculations confirm the promotion of CO 2 reduction reactions by defect chemistry and rich metal-oxide heterostructures. This strategy of constructing heterogeneous interfaces to enhance the cathode electrolysis performance provides new insights into the design of cathode materials for SOEC. The in situ surface modification of metal nanoparticles will significantly increase the oxygen vacancy concentration of the cathode material and reduce the adsorption energy, thus enhancing the catalytic activity of CO 2 RR.