title: Three-dimensional hierarchical frameworks based on MoS₂ nanosheets self-assembled on graphene oxide for efficient electrocatalytic hydrogen evolution.
abstract: Advanced materials for electrocatalytic water splitting are central to renewable energy research. In this work, three-dimensional (3D) hierarchical frameworks based on the self-assembly of MoS2 nanosheets on graphene oxide were produced via a simple one-step hydrothermal process. The structures of the resulting 3D frameworks were characterized by using a variety of microscopic and spectroscopic tools, including scanning and transmission electron microscopies, X-ray diffraction, X-ray photoelectron spectroscopy, and Raman scattering. Importantly, the three-dimensional MoS2/graphene frameworks might be used directly as working electrodes which exhibited apparent and stable electrocatalytic activity in hydrogen evolution reaction (HER), as manifested by a large cathodic current density with a small overpotential of -107 mV (-121 mV when loaded on a glassy-carbon electrode) and a Tafel slope of 86.3 mV/dec (46.3 mV/dec when loaded on a glassy-carbon electrode). The remarkable performance might be ascribed to the good mechanical strength and high electrical conductivity of the 3D frameworks for fast charge transport and collection, where graphene oxide provided abundant nucleation sites for MoS2 deposition and oxygen incorporation led to the formation of defect-rich MoS2 nanosheets with active sites for HER.
authors.affiliation: New Energy Research Institute, School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Center , Guangzhou, Guangdong 510006, China.
authors.forename: Weijia
authors.initials: W
authors.lastname: Zhou
authors.forename: Kai
authors.initials: K
authors.lastname: Zhou
authors.forename: Dongman
authors.initials: D
authors.lastname: Hou
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Liu
authors.forename: Guoqiang
authors.initials: G
authors.lastname: Li
authors.forename: Yuanhua
authors.initials: Y
authors.lastname: Sang
authors.forename: Hong
authors.initials: H
authors.lastname: Liu
authors.forename: Ligui
authors.initials: L
authors.lastname: Li
authors.forename: Shaowei
authors.initials: S
authors.lastname: Chen
keywords: MoS2 nanosheet; electrocatalytic; graphene oxide; hydrogen evolution reaction; hydrothermal; three-dimensional framework