Lattice add-ons with low-content Pd incorporated into Pt nanodendrites revealed active methanol oxidation via the fast removal of poisonous intermediates

Abstract

Methanol-driven fuel cells experience challenges in their performance due to the complex mechanism for the complete conversion of reactants into products. The electrocatalysts undergo partial or strong adsorption of poisonous intermediates during methanol oxidation, which hinders their activity. In this regard, we have designed a facile strategy to develop a catalyst with enhanced and stable methanol electro-oxidation at an economical cost value. The incorporation of lattice add-ons with low-content Pd into Pt nanodendrites (NDs) via the co-reduction single-step method was successfully employed. These Pd-coupled Pt NDs were uniformly dispersed and loaded on reduced graphene oxide (RGO). The PtPd NDs/RGO catalyst exhibited 4 times greater methanol oxidation reaction performance (2 mA cm⁻²) compared to the commercial Pt/C catalyst. Time-resolved in situ Fourier transform infrared (FTIR) spectroscopy and online differential electrochemical mass spectrometry (DEMS) revealed that the methanol oxidation reaction (MOR) followed the active intermediate pathway for its complete conversion into the final product and proceeded through a six-electron transfer reaction.