Evaluating the Effect of B‑Site Cation Doping on the Properties of Pr_0.4Sr_0.5Fe_0.9Mo_0.1O₃ for Reversible Single-Component Cells

Doping different cations into the B-sites of perovskite oxides is often used to increase the concentration of oxygen vacancy (V_o^••), further enhancing their electrocatalytic activity. In this work, Pr_0.4Sr_0.5Co_0.45Fe_0.45Mo_0.1O₃ (PSCFM11), Pr_0.4Sr_0.5Co_0.2Fe_0.7Mo_0.1O₃ (PSCFM27), and Pr_0.4Sr_0.5Ni_0.2Fe_0.7Mo_0.1O₃ (PSNFM27) are synthesized and used as semiconductor materials for the reversible single-component cell (RSCC). In the hydrogen electrode side of the cell, PSCFM11, PSCFM27, and PSNFM27 can be reduced and in situ precipitate Co–Fe alloy and Ni–Fe alloy, and the reduced PSNFM27 exhibits the highest concentration of V_o^••. The single-component fuel cell (SCFC) composed of PSNFM27 and reduced PSNFM27 shows the best cell performance, and the maximum power density is 328.6 mW cm^–2 at 700 °C, indicating the higher concentration of V_o^•• and the higher catalytic activity toward the hydrogen oxidation reaction (HOR). In addition, the RSCC composed of PSNFM27 and reduced PSNFM27 shows the best discharge and water electrolysis performance. The maximum power density of the RSCC can reach 315.3 mW cm^–2, and the electrolysis current density at 1.3V is −612.7 mA cm^–2 at 700 °C.