Strong Electronic Interaction in High-Entropy Oxide Enhances Oxygen Evolution Reaction
Luo Huang, Lixia Ma, Xu Jing, Baoqiang Wei, Yanzhong Xue, Nan Zhang, Xiaojie Zhou, Jie Yang, Zong-Huai Liu, Ruibin Jiang
Abstract
High-entropy oxides are a new type of material with significant application potential. However, the lack of a universal HEO preparation method severely limits the property study and application of HEOs. Herein, we report a universal approach of spray pyrolysis for the preparation of various HEOs and study the electrocatalytic performance of HEOs toward the oxygen evolution reaction. FeCoNiMoWO x HEO exhibits an overpotential of 281 mV at 10 mA cm –2 and a Tafel slope of 34.5 mV dec –1, which are far superior to those of the corresponding medium-entropy oxide and low-entropy oxide. It is found that the high entropy of the HEO greatly strengthens the interaction between Fe and Mo/W and produces abundant oxygen vacancies (OVs) around Mo and W. This work not only provides a universal preparation method for HEOs but also deepens our understanding of OER catalytic activity of HEOs.