Meng Xin-Ying, Wang Meng, Zhang Yicong, Li Zhihao, Ding Xiaogang, Zhang Weiquan, Li Can, Li Zhen
Research & Development Institute of Northwestern Polytechnical University in Shenzhen, Shenzhen, 518057, P. R. China.
State Key Laboratory of Solidification Processing, Center for Nano Energy Materials, School of Materials Science and Engineering, Northwestern Polytechnical University and Shaanxi Joint Laboratory of Graphene (NPU), Xi'an, 710072, P. R. China.
Dalton Trans. 2022 Nov 8;51(43):16605-16611. doi: 10.1039/d2dt02780a.
The oxygen evolution reaction (OER) and alternative urea oxidation reaction (UOR) are both important half reactions correlated with hydrogen production. Transition metal based catalysts with double metal composition exhibit excellent electrocatalytic performance for the OER or UOR due to their synergetic effect and coupling of different active sites. However, the development of OER/UOR bifunctional electrocatalysts is unsatisfying and the role of each metallic active site in the OER and UOR is still unclear. Herein, we report a Fe-Mn based OER and UOR bifunctional catalyst through a simple one-step electrodeposition method. For the OER, the introduction of Mn improves the conductivity of the catalysts and fine-tunes the electron density of the Fe active sites. For the UOR, both Fe and Mn act as active sites and their coupling effect further improves the UOR activity. The catalyst with the optimal Mn/Fe ratio achieved an overpotential of 237 mV for the OER and a potential of 1.35 V for the UOR at 100 mA cm. This study provides a simple synthesis protocol for constructing bifunctional catalysts for green hydrogen production.
析氧反应（OER）和替代性尿素氧化反应（UOR）都是与制氢相关的重要半反应。具有双金属组成的过渡金属基催化剂由于其协同效应和不同活性位点的耦合，对OER或UOR表现出优异的电催化性能。然而，OER/UOR双功能电催化剂的发展并不令人满意，并且每个金属活性位点在OER和UOR中的作用仍不清楚。在此，我们通过一种简单的一步电沉积方法报道了一种基于Fe-Mn的OER和UOR双功能催化剂。对于OER，Mn的引入提高了催化剂的导电性并微调了Fe活性位点的电子密度。对于UOR，Fe和Mn均作为活性位点，它们的耦合效应进一步提高了UOR活性。具有最佳Mn/Fe比的催化剂在100 mA cm时，OER的过电位为237 mV，UOR的电位为1.35 V。本研究为构建用于绿色制氢的双功能催化剂提供了一种简单的合成方案。
