Zuo Shangshang, Liao Yuan, Wang Chenchen, Naden Aaron B, Irvine John T S
School of Chemistry, University of St Andrews, St Andrews, Fife, KY16 9ST, UK.
Small. 2024 Mar;20(11):e2308867. doi: 10.1002/smll.202308867. Epub 2023 Oct 29.
Perovskites are an important class of oxygen evolution reaction (OER) catalysts due to highly tunable compositions and adaptable characteristics. However, perovskite-based catalysts can have limited atom utilization efficiency due to large particle size, resulting in low mass activity. Herein, Cobalt nanoparticles are exsolved from La Ca Ti Co O perovskite and applied in OER. Upon reduction in the 5% H /N atmosphere at 800 °C for 2 h, the Co exsolved perovskite catalyst (R-LCTCo0.11) exhibits optimal OER performance. The mass activity of R-LCTCo0.11 reaches ≈1700 mA mg at an overpotential of 450 mV, which is 17 times and 3 times higher than that of LCTCo0.11 (97 mA mg ) and R-Mix (560 mA mg ) catalysts respectively, surpassing the benchmark catalyst RuO (42.7 mA mg of oxide at η = 470 mV). Electrochemical impedance spectroscopy (EIS) data reveals that R-LCTCo0.11 has the lowest charge transfer resistance (R = 58 Ω), demonstrating the highest catalytic and kinetic activity for OER. Furthermore, this catalyst shows high stability during an accelerated durability test of 10 h electrolysis and 1000 cycles cyclic voltammetry (CV). This work demonstrates that nanoparticle exsolution from a doped perovskite is an effective strategy for improving the atom utilization efficiency in OER.
钙钛矿由于其高度可调的组成和适应性强的特性，是一类重要的析氧反应（OER）催化剂。然而，由于粒径较大，钙钛矿基催化剂的原子利用效率可能有限，导致质量活性较低。在此，钴纳米颗粒从La Ca Ti Co O钙钛矿中析出并应用于OER。在800°C的5%H /N气氛中还原2小时后，析出钴的钙钛矿催化剂（R-LCTCo0.11）表现出最佳的OER性能。R-LCTCo0.11在450 mV过电位下的质量活性达到约1700 mA mg，分别比LCTCo0.11（97 mA mg ）和R-Mix（560 mA mg ）催化剂高17倍和3倍，超过了基准催化剂RuO（在η = 470 mV时为42.7 mA mg的氧化物）。电化学阻抗谱（EIS）数据表明，R-LCTCo0.11具有最低的电荷转移电阻（R = 58 Ω），证明其对OER具有最高的催化和动力学活性。此外，在10小时电解和1000次循环伏安法（CV）的加速耐久性测试中，该催化剂表现出高稳定性。这项工作表明，从掺杂钙钛矿中析出纳米颗粒是提高OER中原子利用效率的有效策略。
