Water induced ultrathin Mo2C nanosheets with high-density grain boundaries for enhanced hydrogen evolution

Yang Yang; Yumin Qian; Zhaoping Luo; Haijing Li; Lanlan Chen; Xumeng Cao; Shiqiang Wei; Bo Zhou; Zhenhua Zhang; Shuai Chen; Wenjun Yan; Juncai Dong; Li Song; Wenhua Zhang; Renfei Feng; Jigang Zhou; Kui Du; Xiuyan Li; Xian-Ming Zhang; Xiujun Fan

doi:10.1038/s41467-022-34976-1

Water induced ultrathin Mo₂C nanosheets with high-density grain boundaries for enhanced hydrogen evolution

Nat Commun. 2022 Nov 24;13(1):7225. doi: 10.1038/s41467-022-34976-1.

Authors

Yang Yang^#^{1

2}, Yumin Qian^#³, Zhaoping Luo⁴, Haijing Li⁵, Lanlan Chen⁶, Xumeng Cao⁴, Shiqiang Wei⁶, Bo Zhou⁷, Zhenhua Zhang⁸, Shuai Chen⁹, Wenjun Yan⁹, Juncai Dong⁵, Li Song⁶, Wenhua Zhang⁶, Renfei Feng¹⁰, Jigang Zhou¹⁰, Kui Du⁴, Xiuyan Li⁴, Xian-Ming Zhang^{11

12}, Xiujun Fan^{13

14}

Affiliations

¹ Institute of Crystalline Materials, Shanxi University, Taiyuan, Shanxi, 030006, China.
² Key Laboratory of Interface Science and Engineering in Advanced Materials, College of Chemistry, College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan, Shanxi, 030024, China.
³ Beijing Key Lab of Nanophotonics and Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Haidian, Beijing, 100081, China.
⁴ Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, 110016, China.
⁵ Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China.
⁶ National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui, 230026, China.
⁷ Institute of Microstructure and Properties of Advanced Materials, Beijing University of Technology, Chaoyang District, Beijing, 100124, China.
⁸ Innovative Center for Advanced Materials, Hangzhou Dianzi University, Hangzhou, Zhejiang, 310018, China.
⁹ Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, 030001, China.
¹⁰ Canadian Light Source, Saskatoon, SK, S7N2V3, Canada.
¹¹ Institute of Crystalline Materials, Shanxi University, Taiyuan, Shanxi, 030006, China. zhangxm@dns.sxnu.edu.cn.
¹² Key Laboratory of Interface Science and Engineering in Advanced Materials, College of Chemistry, College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan, Shanxi, 030024, China. zhangxm@dns.sxnu.edu.cn.
¹³ Institute of Crystalline Materials, Shanxi University, Taiyuan, Shanxi, 030006, China. fxiujun@gmail.com.
¹⁴ Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, School of Chemistry, Xi'an Jiaotong University, Xi'an, 710049, China. fxiujun@gmail.com.

^# Contributed equally.

Abstract

Grain boundary controlling is an effective approach for manipulating the electronic structure of electrocatalysts to improve their hydrogen evolution reaction performance. However, probing the direct effect of grain boundaries as highly active catalytic hot spots is very challenging. Herein, we demonstrate a general water-assisted carbothermal reaction strategy for the construction of ultrathin Mo₂C nanosheets with high-density grain boundaries supported on N-doped graphene. The polycrystalline Mo₂C nanosheets are connected with N-doped graphene through Mo-C bonds, which affords an ultra-high density of active sites, giving excellent hydrogen evolution activity and superior electrocatalytic stability. Theoretical calculations reveal that the d_z² orbital energy level of Mo atoms is controlled by the MoC₃ pyramid configuration, which plays a vital role in governing the hydrogen evolution activity. The d_z² orbital energy level of metal atoms exhibits an intrinsic relationship with the catalyst activity and is regarded as a descriptor for predicting the hydrogen evolution activity.