Highly Efficient A- and B-Site-Doped Ruddlesden–Popper Perovskite Oxide Nd<sub>2–<i>x</i></sub>Sr<sub><i>x</i></sub>Ni<sub>0.9</sub>Cu<sub>0.1</sub>O<sub>4+δ</sub> as a Cathode for PCFCs
Wan‐Ting Wang, Yuan-Ting Wu, Xing-Liang Lin, Zaheer Ud Din Babar, Cheng‐Xin Li, Changqing Liu
Abstract
At medium and low operating temperatures, the slow reaction kinetics of the cathode is a significant limiting factor hindering proton ceramic fuel cell (PCFC) development. This work reports a Nd 2– x Sr x Ni 0.9 Cu 0.1 O 4+δ ( x = 0, 0.2, 0.4, 0.6, 0.8, 1) Ruddlesden–Popper cathode through a combination strategy of A-site Sr 2+ and B-site Cu 2+ codoping. Appropriate Sr 2+ doping has achieved the synergistic optimization of conductivity and electrocatalytic activity by modulating the amount of surface oxygen defects and the valence state of B-site Ni 2+ . Nd 1.4 Sr 0.6 Ni 0.9 Cu 0.1 O 4+δ (NSNC6) exhibits a remarkably improved conductivity (exceeding 100 S cm –1 from 450 to 750 °C) and an enhanced electrocatalytic activity. The PCFC with the NSNC6-BZCNY triple-conducting cathode exhibits sufficient long-term stability and a maximum power density of 445 mW cm –2 at 650 °C, which is approximately 50% higher than that of the PCFC with the NSNC6 cathode, highlighting its potential as a cathode material for PCFCs.