Biomass-based protic ionic liquid derived N, P, co-doped porous carbon-coated CoP nanocrystals for efficient hydrogen evolution reaction

摘要

Biomass-based protic ionic liquids (BILs), green solvents with inherent properties, have the potential as precursors of functionalized catalytic carbon materials. Simple one-step design and preparation of BILs-based porous carbonbased materials remains a challenge. Our demonstration here was to use BIL as an important precursor for synthesizing porous carbon-coated CoP nanocrystals by facile one-pot carbonization process. The as-prepared CoP@NPC-900 has a specific surface area of 979.67 m(2) g(-1) without activator and simultaneously exhibits excellent hydrogen evolution reaction (HER) performance with a low overpotential of 181 mV at 10 mA cm(-2) and small Tafel slope of 59 mV dec(-1) in acid solution. In addition, density functional theory (DFT) calculations indicate lower adsorption free energy and rapid electron transfer between CoP nanocrystals and N, P co-doped porous carbon (NPC) are key factors of improving the HER performance. Our research opens up a new use of BILs, as well as provides a facile strategy to promote practical application of transition metal phosphides for HER. @@@ [GRAPHICS] @@@ .

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