Support engineering modulated Pt/hierarchical MoSe2@mesoporous hollow carbon spheres for efficient methanol-assisted water splitting

Support engineering modulated Pt by hierarchical MoSe2@mesoporous hollow carbon support well addressed the challenges in low intrinsic activity and easy poisoning problems during methanol electrolysis. [Display omitted] •Electrochemical energy conversion from methanol to hydrogen via methanol electrolysis.•Support engineering modulated Pt by hierarchical MoSe2@mesoporous hollow carbon support.•Strong interaction and coupling ability between Pt and MoSe2 regulated the active centers.•Weakened binding strength of COad and Had intermediates during catalysis.•High electrochemical properties due to enhanced oxophilicity and poisoning tolerance ability. Hydrogen generation from methanol via methanol-assisted water splitting is a promising electrochemical energy conversion technology but still meets challenges in addressing the low intrinsic activity and easy poisoning problems of the conventional Pt catalysts. Herein, the support engineering modulated Pt by hierarchical MoSe2@mesoporous hollow carbon support was proposed to integrate some structural and catalytic advantages for hydrogen evolution reaction (HER) and methanol oxidation reaction (MOR). Supporting engineering by layered MoSe2 nanosheets confined in mesoporous hollow carbon spheres (MHCSs) is adopted to uniformly anchor Pt nanoparticles (Pt/MoSe2@MHCS), which effectively enhances the conductivity and prevents the layer-by-layer stacking of MoSe2; Strong interaction and coupling ability between Pt and MoSe2 and the resultant electronic structure regulation of the active centers could weaken the binding strength of CO* and H* intermediates during catalysis and strengthen the oxophilicity leading to improved MOR and HER kinetics. Specifically, Pt/MoSe2@MHCS shows a significantly improved MOR current density of 81.1 mA cm−2, about 3.0 times that of the benchmark Pt/C catalyst. Meanwhile, it also exhibits the HER performance of 28 mV to achieve a kinetic current density of 10 mA cm−2 in methanol-contained electrolytes. When employed for overall methanol electrolysis, a lowered input voltage of 1.11 V can be obtained to drive the current density (10 mA cm−2) compared to that for water electrolysis (0.62 V vs. 1.73 V). The electrochemical properties of high activity, rapid catalytic kinetics, and good stability were also demonstrated due to the enhanced oxophilicity and high poisoning tolerance ability resulting from the MoSe2/carbon substrate-induced electron redistribution of Pt sites. This work reports a