Surface reconstruction of defective SrTi_0.7Cu_0.2Mo_0.1O_3-δ perovskite oxide induced by in-situ copper nanoparticle exsolution for high-performance direct CO₂ electrolysis

Solid oxide electrolysis cell (SOEC) provides an effective solution to electrochemically convert CO₂ into valuable products with high efficiency, which is also developed as a promising way for the electricity utilization. However, the poor catalytic activity of the electrode material results in slow cathode kinetics for this technology. In this work, we propose a series of Sr_xTi_0.7Cu_0.2Mo_0.1O_3-δ (S_xTCM, x = 1, 0.975, 0.95) perovskite oxides as the cathodes of SOEC. By tuning the defects of the materials, abundant oxygen vacancies are stimulated in the perovskite lattice, which effectively improves the oxygen ion transport capacity and also act as the receptors of CO₂ molecule. Uniformly dispersed Cu nanoparticles on STCM substrate are in-situ generated after reduction treatment, leading to the formation of abundant active sites for CO₂ reduction reaction (CO₂RR). The results of this work demonstrate a general strategy for developing promising catalysts for efficient CO₂RR.