Ag nanoparticles modified crumpled borophene supported Co3O4 catalyst showing superior oxygen evolution reaction (OER) performance

Abstract

Herein, we report borophene decorated with Ag nanoparticles (Ag@B) as a support, which shows greatly enhanced oxygen-evolution-reaction (OER) performance for Co3O4 catalysts. The excellent OER performance of Co3O4-Ag@B is attributed into two main reasons. First, the conductive Ag-nanoparticles on borophene facilitate the growth of thin Co3O4 nanoplates based on an epitaxy model that greatly enhances the population of Co3O4 catalyst sites on the surface. In the meantime, Ag nanoparticles increase the electrical conductivity of the support, facilitating electrons-transfer from CoⅢ atoms to form catalytically-active CoⅣ sites. Second, the B atoms strongly interact with Co and O atoms on the Co3O4 nanoplates, greatly reducing the energy barrier of OER rate-determining procedure and increasing their stability on borophene supports. The Co3O4-Ag@B requires an overpotential of 270 mV and exhibits a Tafel-slope of 62 mV dec−1 to deliver an oxygen-evolving current-density of 10 mA cm−2, indicating 60 mV lower overpotential and 27 mV dec−1 lower Tafel-slop value than the Co3O4-Ag@rGO catalysts.