Formic acid decomposition-inhibited intermetallic Pd3Sn2 nanonetworks for efficient formic acid electrooxidation

Abstract

Inhibiting formic acid decomposition on Pd-based electrocatalysts is a major challenge for realizing the commercialization of direct formic acid fuel cells (DFAFCs). Inspired by the catalytic characteristics of formic acid decomposition/electrooxidation on Pd-based materials, here we synthesize intermetallic bimetallic Pd–Sn nanonetworks (NNWs) to deal with this problem. Compared to commercial Pd black with high catalytic activity, the strong Pd–Sn electronic interaction in intermetallic Pd3Sn2 NNWs induces the complete inhibition of formic acid decomposition at 80 °C. Parallelly, Pd3Sn2 NNWs exhibit mass activity of 448 A gPd−1 for formic acid electrooxidation due to Pd–Sn synergistic effect, which is 2.1 times higher than that of commercial Pd black. The stable intermetallic structure and three-dimensionally interconnected architecture endow Pd3Sn2 NNWs with better electrochemical and electrocatalytic durability, suggesting promising cost-effective anode catalysts for DFAFCs.