Interstitial Hydrogen Atom Modified PdPt Nanosheets for Efficient Ethanol Electro-oxidation with High C–C Bond Cleavage Selectivity

Direct ethanol fuel cells (DEFCs) are a type of promising portable power source with low environmental pollution and high energy density. However, the further commercialization of DEFCs is hindered by the incomplete oxidation of ethanol on the electrocatalysts. Herein, we report a successful synthesis of ultrathin PdPtH nanosheets (NSs) for the first time by the in situ formation of interstitial hydrogen atoms accompanied by wet-chemical coreduction of Pd and Pt precursors. The PdPtH NSs possess selectivity of 15.1% related to C–C bond splitting for ethanol complete oxidation to CO2 through the C1 pathway at a low potential, while the contrast selectivity is 4.8% for Pt black, 9.2% for commercial Pd black, and 11.7 for PdH NSs, respectively. Accordingly, the PdPtH NSs exhibited enhanced catalytic activity in comparison to the counterparts. The mass activity toward ethanol oxidation reaction (EOR) of the PdPtH NSs is 5.2 times and 87 times higher than that of commercial Pd and commercial Pt, respectively. The structure stability and growth mechanism of the PdPtH NSs were also investigated. The results of in situ Fourier transform infrared spectra revealed a stronger C–C bond cleavage ability and CO stripping shows the better antipoisoning properties of the PdPtH NSs arising from the cooperation of the PdPt alloy with interstitial H atoms.