Boosting oxygen reduction reaction with metal phthalocyanines: altering central metals and substituents

Abstract

Metal phthalocyanines (MPcs), as non-precious metal catalysts, have shown great promise in catalyzing the Oxygen Reduction Reaction (ORR). However, understanding their electronic structures during ORR and their impact on catalytic performance is still limited. In this work, we employed density functional theory (DFT) to investigate strategies to modulate the electronic structures of MPcs by altering central metals and introducing substituents. Our study revealed that changing central metals regulates the adsorption of key intermediate OOH* and promotes ORR activity. Subsequently, we introduced different substituents to optimize OOH* adsorption, achieving a low overpotential of only 0.37 V. Moreover, we proposed a novel bond order scheme to describe OOH* adsorption strength and the electronic origin of ORR activity. Our findings offer valuable insights into catalyst design for enhancing electrochemical reactions.