Encapsulating dual-phased Mo2C-WC nanocrystals into ultrathin carbon nanosheet assemblies for efficient electrocatalytic hydrogen evolution

作者:Zhang, Xueting; Zhu, Zhenye*; Liang, Xiongyi; Ma, Fei-Xiang*; Zhang, Jiaheng*; Tan, Yuanbo; Pan, Zuchen; Bo, Yiyang; Wu, Chi-Man Lawrence
来源:Chemical Engineering Journal, 2021, 408: 127270.
DOI:10.1016/j.cej.2020.127270

摘要

Mo2C and WC are widely considered as promising electrocatalysts for hydrogen evolution reaction (HER) owing to their Pt-like electronic features. Herein, dual-phased Mo2C-WC nanocrystals, densely and uniformly confined in ultrathin carbon nanosheet assemblies (abbreviated as Mo2C-WC/NCAs), which are possible candidates for high-performance HER electrocatalysts, are fabricated through the in-situ pyrolysis of polymers containing Mo and W. When evaluated as HER electrocatalysts, Mo2C-WC/NCAs requires a small overpotential of similar to 126 mV to drive a current density of 10 mA cm(-2), and low Tafel slopes of 72 mV dec(-1) and 59 mV dec(-1) in acidic and alkaline media, respectively. In addition, the Mo2C-WC/NCAs exhibit robust catalytic stability up to 36 h. The introduction of dual-phased carbide heterostructures can modify the electronic structure and simultaneously facilitate the charge transfer of the catalysts, consistent with the density functional theory (DFT) calculations. This work highlights the in-situ construction of multi-phased hetero-metal carbide heterostructures for high-performance electrocatalysis.

  • 单位
    香港城市大学; harbin inst technol shenzhen

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