Designing highly efficient oxygen evolution reaction electrocatalyst of high-entropy oxides FeCoNiZrOx: Theory and experiment
Haiqing Zhao, Tao Wang, Can Li, Miaogen Chen, Lengyuan Niu, Yinyan Gong
Abstract
The correlations between the experimental methods and catalytic activities are urgent to be defined for the design of highly efficient catalysts. In this work, a new oxygen evolution reaction electrocatalyst of high-entropy oxide (HEO) FeCoNiZrO x was designed and analyzed by experimental and theoretical methods. On account of the shortened coordinate bond along with the increased annealing temperature, the atomic/electronic structures of active site were adjusted quantitatively with the aid of the pre-designed correlator of d electron density, which contributed to adjust the catalytic activity of HEO specimens. The prepared HEO specimen exhibited the low overpotentials of 245 mV at 10 mA cm −2 and 288 mV at 100 mA cm −2 with small Tafel slope of 35.66 mV dec −1 , fast charge transfer rate, and stable electrocatalytic activity. This strategy would be adopted to improve the catalytic activity of HEO by adjusting the d electron density of transition metal ions with suitable preparation method.