Comprehensive electrochemical study on SrMo0.2Fe0.8O3-δ perovskite electrodes for symmetrical solid oxide cells

Solid oxide cells (SOCs) have shown great potential for the development of renewable energy systems in terms of power generation and energy conversion efficiency. However, in the traditional structural design of SOCs, thermal asymmetry between components can easily occur during the transition between different operating modes, leading to issues such as thermal stress. Therefore, it is particularly important to develop electrode materials suitable for symmetrical solid oxide cells (SSOCs) to address this challenge. In this study, SrMo 0.2 Fe 0.8 O 3- δ (SMF) is employed as both an air electrode and a fuel electrode material. By precisely controlling the reduction temperature, the exsolution of Fe nanoparticles on the surface of SMF can effectively enhance catalytic activity and improve electrochemical performance. In fuel cell mode, the peak power density (PPD) of electrolyte-supported symmetrical single cells attains 0.80 W cm −2 at 850 °C. In electrolytic cell mode, the electrolysis current density achieves −0.94 A cm −2 at 1.3 V and 850 °C for 30 % H 2 O, while pure CO 2 electrolysis delivers a current density of −1.17 A cm −2 at 1.5 V. The SSOCs exhibit good durability in both modes, indicating that SMF is a promising electrode candidate for SSOCs.