title: Heterogeneous Spin States in Ultrathin Nanosheets Induce Subtle Lattice Distortion To Trigger Efficient Hydrogen Evolution.
abstract: The exploration of efficient nonprecious metal eletrocatalysis of the hydrogen evolution reaction (HER) is an extraordinary challenge for future applications in sustainable energy conversion. The family of first-row-transition-metal dichalcogenides has received a small amount of research, including the active site and dynamics, relative to their extraordinary potential. In response, we developed a strategy to achieve synergistically active sites and dynamic regulation in first-row-transition-metal dichalcogenides by the heterogeneous spin states incorporated in this work. Specifically, taking the metallic Mn-doped pyrite CoSe2 as a self-adaptived, subtle atomic arrangement distortion to provide additional active edge sites for HER will occur in the CoSe2 atomic layers with Mn incorporated into the primitive lattice, which is visually verified by HRTEM. Synergistically, the density functional theory simulation results reveal that the Mn incorporation lowers the kinetic energy barrier by promoting H-H bond formation on two adjacently adsorbed H atoms, benefiting H2 gas evolution. As a result, the Mn-doped CoSe2 ultrathin nanosheets possess useful HER properties with a low overpotential of 174 mV, an unexpectedly small Tafel slope of 36 mV/dec, and a larger exchange current density of 68.3 μA cm(-2). Moreover, the original concept of coordinated regulation presented in this work can broaden horizons and provide new dimensions in the design of newly highly efficient catalysts for hydrogen evolution.
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science & Technology of China , Hefei, Anhui 230026, P. R. China.
authors.forename: Youwen
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science & Technology of China , Hefei, Anhui 230026, P. R. China.
authors.forename: Xuemin
authors.initials: X
authors.lastname: Hua
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science & Technology of China , Hefei, Anhui 230026, P. R. China.
authors.forename: Chong
authors.initials: C
authors.lastname: Xiao
authors.affiliation: Institute for Superconducting and Electronic Materials, Australian Institute for Innovative Materials (AIIM), and School of Mechanical, Materials and Mechatronics Engineering, University of Wollongong , North Wollongong, NSW 2500, Australia.
authors.forename: Tengfei
authors.initials: T
authors.lastname: Zhou
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science & Technology of China , Hefei, Anhui 230026, P. R. China.
authors.forename: Pengcheng
authors.initials: P
authors.lastname: Huang
authors.affiliation: Institute for Superconducting and Electronic Materials, Australian Institute for Innovative Materials (AIIM), and School of Mechanical, Materials and Mechatronics Engineering, University of Wollongong , North Wollongong, NSW 2500, Australia.
authors.forename: Zaiping
authors.initials: Z
authors.lastname: Guo
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science & Technology of China , Hefei, Anhui 230026, P. R. China.
authors.forename: Bicai
authors.initials: B
authors.lastname: Pan
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science & Technology of China , Hefei, Anhui 230026, P. R. China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Xie