Phase Modulation of (1T-2H)-MoSe2/TiC-C Shell/Core Arrays via Nitrogen Doping for Highly Efficient Hydrogen Evolution Reaction

Shengjue Deng; Fan Yang; Qinghua Zhang; Yu Zhong; Yinxiang Zeng; Shiwei Lin; Xiuli Wang; Xihong Lu; Cai-Zhuang Wang; Lin Gu; Xinhui Xia; Jiangping Tu

doi:10.1002/adma.201802223

Phase Modulation of (1T-2H)-MoSe2/TiC-C Shell/Core Arrays via Nitrogen Doping for Highly Efficient Hydrogen Evolution Reaction

Adv Mater. 2018 Jul 5:e1802223. doi: 10.1002/adma.201802223. Online ahead of print.

Authors

Shengjue Deng¹, Fan Yang², Qinghua Zhang³, Yu Zhong¹, Yinxiang Zeng⁴, Shiwei Lin², Xiuli Wang¹, Xihong Lu⁴, Cai-Zhuang Wang⁵, Lin Gu³, Xinhui Xia¹, Jiangping Tu¹

Affiliations

¹ State Key Laboratory of Silicon Materials, Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province, and Department of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, P. R. China.
² State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, 570228, P. R. China.
³ Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
⁴ MOE of the Key Laboratory of Bioinorganic and Synthetic Chemistry, KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou, 510275, China.
⁵ Ames Laboratory, U. S. Department of Energy, and Department of Physics and Astronomy, Iowa State University, Ames, IA, 50011, USA.

PMID: 29975803
DOI: 10.1002/adma.201802223

Abstract

Tailoring molybdenum selenide electrocatalysts with tunable phase and morphology is of great importance for advancement of hydrogen evolution reaction (HER). In this work, phase- and morphology-modulated N-doped MoSe₂ /TiC-C shell/core arrays through a facile hydrothermal and postannealing treatment strategy are reported. Highly conductive TiC-C nanorod arrays serve as the backbone for MoSe₂ nanosheets to form high-quality MoSe₂ /TiC-C shell/core arrays. Impressively, continuous phase modulation of MoSe₂ is realized on the MoSe₂ /TiC-C arrays. Except for the pure 1T-MoSe₂ and 2H-MoSe₂ , mixed (1T-2H)-MoSe₂ nanosheets are achieved in the N-MoSe₂ by N doping and demonstrated by spherical aberration electron microscope. Plausible mechanism of phase transformation and different doping sites of N atom are proposed via theoretical calculation. The much smaller energy barrier, longer HSe bond length, and diminished bandgap endow N-MoSe₂ /TiC-C arrays with substantially superior HER performance compared to 1T and 2H phase counterparts. Impressively, the designed N-MoSe₂ /TiC-C arrays exhibit a low overpotential of 137 mV at a large current density of 100 mA cm^-2 , and a small Tafel slope of 32 mV dec^-1 . Our results pave the way to unravel the enhancement mechanism of HER on 2D transition metal dichalcogenides by N doping.

Keywords: core/shell arrays; hydrogen evolution reaction; molybdenum selenide; nitrogen doping; phase modulation.