Three-dimensional porous rhodium–copper alloy nanoflowers stereoassembled on Ti3C2Tx MXene as highly-efficient methanol oxidation electrocatalysts†

Abstract

The development of direct methanol fuel cell technology is expected to ease the excessive consumption of non-renewable fossil fuels, which puts forward a new request for the exploration of advanced Pt-alternative electrocatalysts toward the methanol oxidation reaction (MOR). Here, we demonstrate a facile and robust bottom-up method for the spatial construction of three-dimensional (3D) porous rhodium–copper alloy nanoflowers stereoassembled on Ti₃C₂T_x MXene nanosheets (RhCu NF/Ti₃C₂T_x) through an in situ soft-chemistry process. With the synergistic contributions from the distinctive structural merits, such as the 3D nanoflower-shaped configuration, abundant porosity, bimetallic alloy and strain effects, and excellent metallic conductivity, the resultant RhCu NF/Ti₃C₂T_x nanoarchitectures manifest significantly boosted electrocatalytic MOR performance under alkaline conditions, which is more competitive than that of conventional particle-shaped Rh catalysts dispersed on Ti₃C₂T_x nanosheets, graphene, carbon nanotubes, carbon black and commercial Pt/carbon black and Pd/carbon black catalysts.