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Ultrasmall and phase-pure W2C nanoparticles for efficient electrocatalytic and photoelectrochemical hydrogen evolution

2016; Nature Portfolio; Volume: 7; Issue: 1 Linguagem: Inglês

10.1038/ncomms13216

2041-1723

Qiufang Gong, Yu Wang, Qi Hu, Jigang Zhou, Renfei Feng, Paul N. Duchesne, Peng Zhang, Fengjiao Chen, Na Han, Yafei Li, Chuanhong Jin, Yanguang Li, Shuit‐Tong Lee,

Advanced Photocatalysis Techniques

Abstract Earlier research has been primarily focused on WC as one of the most promising earth-abundant electrocatalysts for hydrogen evolution reaction (HER), whereas the other compound in this carbide family—W 2 C—has received far less attention. Our theoretical calculations suggest that such a focus is misplaced and W 2 C is potentially more HER-active than WC. Nevertheless, the preparation of phase pure and sintering-free W 2 C nanostructures represents a formidable challenge. Here we develop an improved carburization method and successfully prepare ultrasmall and phase-pure W 2 C nanoparticles. When evaluated for HER electrocatalysis, W 2 C nanoparticles exhibit a small onset overpotential of 50 mV, a Tafel slope of 45 mV dec −1 and outstanding long-term cycling stability, which are dramatically improved over all existing WC-based materials. In addition, the integration of W 2 C nanoparticles with p-type Si nanowires enables highly active and sustainable solar-driven hydrogen production. Our results highlight the great potential of this traditionally non-popular material in HER electrocatalysis.