Bimetal Prussian Blue as a Continuously Variable Platform for Investigating the Composition-Activity Relationship of Phosphides-Based Electrocatalysts for Water Oxidation

Abstract

Doping unary transition-metal phosphides (TMPs) by secondary metal is a powerful method to improve their catalytic activity for electrochemical oxygen evolution reaction (OER). However, the composition-activity relationship of such doping has not been systematically investigated yet because of the challenge in constructing bimetal TMPs with continuously variable composition while keeping homogenous elemental distribution. Herein, we develop a strategy of using bimetal Prussian blue analogues with homogenous elemental distribution at molecular scale as an ideal platform to achieve bimetal cobalt-iron phosphides (Co1- xFe xP) with a continuously changeable Co/Fe ratio (0 < x < 1) and uniform m..