Song Xiaoyun, Yang Qimei, Chen Zebi, Zou Kaisheng, Xie Zhenyang, Ding Wei, Wei Zidong
State Key Laboratory of Advanced Chemical Power Sources (SKL-ACPS), School of Chemistry and Chemical Engineering, Center of Advanced Electrochemical Energy (CAEE), Institute of Advanced Interdisciplinary Studies, Chongqing University, Chongqing, 400044, China.
Small. 2024 Oct;20(40):e2402701. doi: 10.1002/smll.202402701. Epub 2024 Jun 14.
The inevitable oxidation of nickel-metal-based catalysts exposed to the air will lead to instability and poor reproducibility of a catalytic interface, which is usually ignored and greatly hinders their application for the catalysis of alkaline hydrogen oxidation. The details on the formation of a world-class nickel-based HOR catalyst Ni-MoO/C-500 are reported via an interfacial reconstruction triggered by passive oxidation upon air exposure. Interfacial reconstruction, initiated with various Ni-Mo metal ratios and annealing temperature, can fine-tune the Ni-Mo interface with an increased work function and a reduced d-band center. The optimized Ni-MoO/C exhibits a record high mass activity of 102.8 mA mg , a top-level exchange current density of 76.5 µA cm , and exceptional resistance to CO poisoning at 1000 ppm CO for hours. The catalyzed alkaline exchange membrane fuel cell exhibits a maximum power output of 600 mW cm and excellent stability, ranking it as one of the most active non-precious metals HOR catalysts to date.
暴露在空气中的镍基金属催化剂不可避免的氧化会导致催化界面的不稳定性和可重复性差，这一问题通常被忽视，并且极大地阻碍了它们在碱性氢氧化催化中的应用。通过空气暴露时被动氧化引发的界面重构，报道了世界级镍基氢氧化催化剂Ni-MoO/C-500形成的详细情况。以各种镍钼金属比例和退火温度引发的界面重构，可以通过增加功函数和降低d带中心来微调镍钼界面。优化后的Ni-MoO/C展现出创纪录的102.8 mA mg的高质量活性、76.5 µA cm的顶级交换电流密度，以及在1000 ppm CO环境下数小时的出色抗CO中毒能力。催化的碱性交换膜燃料电池展现出600 mW cm的最大功率输出和出色的稳定性，使其成为迄今为止最具活性的非贵金属氢氧化催化剂之一。
