Xu Zhenhang, Zuo Wei, Shi Tianyu, Liu Xinghai, Li Houbin, Zhao Pingping, Cheng Gongzhen
College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, Hubei, 430072, P. R. China.
School of Printing and Packaging, Wuhan University, Wuhan, Hubei, 430072, P. R. China.
Dalton Trans. 2022 Feb 22;51(8):3137-3145. doi: 10.1039/d1dt03936a.
In the context of the ever-increasing energy crisis, electrocatalytic water splitting has attracted widespread attention as an effective means to provide clean energy. However, the oxygen evolution reaction (OER), which is an important anodic half reaction, shows very slow kinetics due to the multi-step electron transfer process, which severely restricts the efficiency of energy conversion. Herein, we used a simple solvothermal method to dope iron into the cobalt-containing hydroxide precursor, and successfully prepared the Fe-doped Co-oxide electrocatalyst CoFeO-0.01. It only needs an overpotential of 294 mV to perform the OER at a current density of 10 mA cm, and has a low Tafel slope of 47.3 mV dec. Moreover, CoFeO-0.01 has excellent stability. There is no significant increase in the overpotential for oxygen evolution at a current density of 10 mA cm after nearly 20 h. BET surface area test and XPS spectroscopy results show that Fe doping provides more mesopores and oxygen bridges, which is conducive to the construction of active sites and electronic regulation during the OER. This work can help design more bimetallic based highly active OER materials.
在日益严重的能源危机背景下，电催化水分解作为一种提供清洁能源的有效手段受到了广泛关注。然而，析氧反应（OER）作为重要的阳极半反应，由于其多步电子转移过程，动力学非常缓慢，这严重限制了能量转换效率。在此，我们采用简单的溶剂热法将铁掺杂到含钴氢氧化物前驱体中，成功制备了铁掺杂的钴氧化物电催化剂CoFeO-0.01。在电流密度为10 mA cm时，它仅需294 mV的过电位就能进行析氧反应，并且具有47.3 mV dec的低塔菲尔斜率。此外，CoFeO-0.01具有优异的稳定性。在电流密度为10 mA cm下经过近20小时的析氧反应后，过电位没有显著增加。BET表面积测试和XPS光谱结果表明，铁掺杂提供了更多的中孔和氧桥，这有利于在析氧反应过程中活性位点的构建和电子调控。这项工作有助于设计更多基于双金属的高活性析氧反应材料。
