Palladium Phosphide Supported on 3D Nitrogen‐Doped Reduced Graphene Oxide for Efficient Formic Acid Electro‐Oxidation

Abstract

Abstract The operational, sustainability, safety, energy, and power advantages of direct formic acid fuel cells (DFAFCs) have established them as promising direct liquid fuel cell (DLFC) setups suitable for powering portable electronic devices and electric vehicles. However, the unavailability of cost‐effective, stable, and efficient anode materials continues to hamper the large‐scale commercialization of DFAFCs. Herein, we report a simple, easily scalable, one‐pot hydrothermal strategy for the synthesis of nanoscale palladium phosphide (PdP) loaded three‐dimensional nitrogen‐doped graphene (3D‐NrGO/PdP) composites as a potential anode electrocatalyst for formic acid electro‐oxidation (FAEO). The stability and electrocatalytic activity of 3D‐NrGO/PdP are shown to be strongly composition sensitive, with 3D‐NrGO/PdP(2:1) (Pd:P ratio of 2:1) composite exhibiting the highest activity, stability, and tolerance to higher concentrations of formic acid under DFAFCs relevant conditions. The exceptionally high electrochemically active surface area, high electronic conductivity, and positive synergism among the components of optimally composed 3D‐NrGO/PdP(2:1) composite are demonstrated to endow it with excellent electrochemical stability, low resistance to charge transfer, and hence high electrocatalytic performance toward FAEO. The excellent stability and electrocatalytic performance (mass activity) as observed for the 3D‐NrGO/PdP(2:1) composite in the present work is far better than those reported till date for FAEO.