Easy preparation of multifunctional ternary PdNiP/C catalysts toward enhanced small organic molecule electro-oxidation and hydrogen evolution reactions

Abstract

The small organic molecule electro-oxidation (OMEO) and the hydrogen evolution (HER) are two important half-reactions in direct liquid fuel cells (DLFCs) and water electrolyzers, respectively, whose performance is largely hindered by the low activity and poor stability of electrocatalysts. Herein, we demonstrate that a simple phosphorization treatment of commercially available palladium-nickel (PdNi) catalysts results in multifunctional ternary palladium nickel phosphide (PdNiP) catalysts, which exhibit substantially enhanced electrocatalytic activity and stability for HER and OMEO of a number of molecules including formic acid, methanol, ethanol, and ethylene glycol, in acidic and/or alkaline media. The improved performance results from the modification of electronic structure of palladium and nickel by the introduced phosphorus and the enhanced corrosion resistance of PdNiP. The simple phosphorization approach reported here allows for mass production of highly-active OMEO and HER electrocatalysts, holding substantial promise for their large-scale application in direct liquid fuel cells and water electrolyzers.