Three-dimensional MoS2/rGO hydrogel with extremely high double-layer capacitance as active catalyst for hydrogen evolution reaction. (10th November 2015)

• Record Type: Journal Article
• Authors: Zhang, Junma; Zhao, Li; Liu, Aiping; Li, Xiaoyun; Wu, Huaping; Lu, Congda
• Is Part Of: Electrochimica acta. Volume 182(2015)
• Page Start: 652
• Page End: 658
• Publication Date: 2015-11-10
• Subjects: Three-dimensional hydrogel -- MoS2/rGO hybrids -- hydrogen evolution reaction -- hydrothermal method; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2015.09.147
• Languages: English
• ISSNs: 0013-4686

Abstract

Graphical abstract: Highlights: One-pot hydrothermal synthesis of MoS2 /rGO hydrogels for HER. MoS2 /rGO hydrogel showed extremely high double-layer capacitance. Electrocatalytic activity for HER with a small Tafel slope of 41 mV/decade. Synergetic effect between MoS2 and rGO nanosheets. Abstract: Three-dimensional (3D) molybdenum disulfide/reduced graphene oxide (MoS2 /rGO) hydrogels were developed by a simple and controllable one-pot hydrothermal method. The MoS2 nanosheets were uniformly anchored on the 3D rGO framework with strong adhesion. The obtained MoS2 /rGO hydrogel with optimized rGO percentage showed extremely high double-layer capacitance about 29.60 mF/cm 2 due to the special 3D network structure. Electrochemical measurements confirmed that the MoS2 /rGO hydrogel exhibited excellent electrocatalytic activity for hydrogen evolution reaction (HER) with a small onset overpotential of 125 mV and Tafel slope of 41 mV/decade, indicating the Volmer-Heyrovsky mechanism during the HER process and the electrochemical desorption step as rate-limiting step. Our results demonstrated that the 3D MoS2 /rGO hydrogel could not only provide rich active sites for HER due to the inhibition of re-stacking process of (0 0 2) planes of MoS2 nanosheets along the C-axis, but also greatly contribute to the enlarged electrochemical surface area because of the formation of 3D network structure in the self-assembly process. This may open up a potential way to design advanced materials for HER.