Facile synthesis of Fe2P/Co embedded trifunctional electrocatalyst for high-performance anion exchange membrane fuel cells, rechargeable Zn–air batteries, and overall water splitting

Abstract

Designing highly active multifunctional catalysts to meet the demands for fuel cells, metal–air batteries, and water-splitting devices is a top priority. Here, an efficient and novel trifunctional electrocatalyst (Fe₂P/Co@NPC) with Fe₂P and Co nanoparticles embedded in porous carbon has been developed by facile one-pot pyrolysis. The synergistic effect of Fe₂P and Co nanoparticles furnishes Fe₂P/Co@NPC with excellent catalytic performance for oxygen reduction reaction (ORR, E_1/2 = 0.876 V), oxygen evolution reaction (OER, η₁₀ = 331 mV), and hydrogen evolution reaction (HER, η₁₀ = 235 mV). Significantly, using Fe₂P/Co@NPC catalyst as the cathode, the assembled anion exchange membrane fuel cell delivers a peak power density of 1.25 W cm⁻². Moreover, the assembled rechargeable Zn–air battery, using Fe₂P/Co@NPC as a bifunctional oxygen catalyst, exhibits a maximum power density of 233.56 mW cm⁻² and impressive cycle performance. Using Fe₂P/Co@NPC as a bifunctional HER and OER catalyst, the overall water electrolyzer also achieves a low voltage of 1.73 V to deliver 10 mA cm⁻². This work represents a protocol for the preparation of high efficient trifunctional electrocatalysts using cheaper heteroatom-containing metal–organic small molecules as a precursor for electrochemical energy devices.