Phosphorus-doping-tuned PtNi concave nanocubes with high-index facets for enhanced methanol oxidation reaction

Abstract

Surface engineering has been found to be an efficient strategy to boost the catalytic performance of noble-metal-based nanocatalysts. In this work, a small amount of P was doped to the surface of PtNi concave cube (P-PtNi CNC). Interestingly, the P-PtNi CNC nanocatalyst shows an enhanced methanol oxidation reaction (MOR) performance with achieving 8.19 times of specific activity than that of comercial Pt/C. The electrochemical in situ Fourier transform infrared spectroscopy (FTIR) results reveal that the surface P doping promotes the adsorption energy of OH, enhancing the resistance against CO poisoning. Therefore, the intermediate adsorbed CO (COads) reacted with adsorbed OH (OHads) through the Langmuir—Hinshelwood (LH) mechanism to generate CO2 and release surface active sites for further adsorption. This work provides a promising strategy via the incorporation of non-metallic elements into the PtNi alloys bounded with high-index facets (HIFs) as efficient fuel cell catalysts.