Synthesis and Evaluation of Reduced Graphene Oxide (rGO) Supported on Ni₃O₄ as Spinel‐Based Cathode Catalyst for the Effective Anion‐Exchange Membrane Fuel Cell Application

Abstract Oxygen reduction reaction (ORR) stability and catalytic activity in high‐durability anion exchange membrane fuel cells (AEMFCs) can be improved using graphene‐supported spinel‐based Ni 3 O 4 cathode catalysts. Here, we describe a simple and economical hydrothermal method for synthesizing reduced graphene oxide (rGO) supported on Ni 3 O 4 . The atomic‐level contribution of the Ni−Ni and Ni−O bonds to the chemical structure of nickel oxide was confirmed by X‐ray photoelectron and absorption spectroscopy studies. Due to the force of the void for oxygen created by nickel atoms, Ni 3 O 4 @rGO for the ORR exhibited enhanced stability and catalytic activity (E 1/2= 0.761 V and over 30,000 CV cycles). A single AEMFC cell achieved the greatest power density and long‐term durability using a Ni 3 O 4 @rGO cathode, suggesting improved endurance despite the minimal voltage decrease (power density 29.6 mW cm −2 , endurance for 25 h). These findings offer insights and point to opportunities for developing metal oxide–based AEMFCs.