A F-doped high-entropy perovskite as a SOC electrode for stable CO2 electrolysis and power generation

The Sr element in Sr-containing perovskites tends to segregate, resulting in structural instability of these materials, especially in a CO 2 -rich atmosphere. This study introduces a structurally robust high-entropy F-doped perovskite La 0.2 Pr 0.2 Sm 0.2 Sr 0.2 Ca 0.2 FeO 2.9-δ F 0.1 (F-LPSSCF), specifically engineered for use as an electrode in CO 2 electrolysis and power generation. The high entropy nature of this material confers both chemical and thermal stability. Additionally, F-doping significantly improves the chemisorption and binding affinity of CO 2 to the perovskite. When employed as an electrode in a solid oxide electrolysis cell (SOEC) for CO 2 electrolysis, F-LPSSCF exhibits remarkable CO 2 conversion efficiency, exceeding that of La 0.2 Pr 0.2 Sm 0.2 Sr 0.2 Ca 0.2 FeO 3-δ (LPSSCF). The F-LPSSCF-based cell also exhibited long-term stability, maintaining its performance for over 300 h at 800 °C and 1.2 V. This remarkable performance is attributed to the improved interaction between F-LPSSCF and CO 2 , as confirmed by DFT calculations. In solid oxide fuel cell (SOFC) mode, the performance of the F-LPSSCF-based cell outperformed that of the LPSSCF-based cell. This study offers a promising approach for the development of durable electrodes aimed at CO 2 electrolysis via SOECs and power generation via SOFC. • A structurally robust high-entropy perovskite La 0.2 Pr 0.2 Sm 0.2 Sr 0.2 Ca 0.2 FeO 2.9-δ F 0.1 (F-LPSSCF) was prepared. • F-doping induced the CO 2 adsorption/activation and eCO 2 RR catalytic performance. • F-LPSSCF-based symmetric cell showed high electrocatalytic activity for CO 2 reduction, ORR and HER.