posted on 2019-10-02, 15:03authored byH Dong, C Liu, H Ye, L Hu, B Fugetsu, W Dai, Y Cao, X Qi, H Lu, X Zhang
An efficient three-dimensional (3D) hybrid material of nitrogen-doped graphene sheets (N-RGO) supporting molybdenum disulfide (MoS(2)) nanoparticles with high-performance electrocatalytic activity for hydrogen evolution reaction (HER) is fabricated by using a facile hydrothermal route. Comprehensive microscopic and spectroscopic characterizations confirm the resulting hybrid material possesses a 3D crumpled few-layered graphene network structure decorated with MoS(2) nanoparticles. Electrochemical characterization analysis reveals that the resulting hybrid material exhibits efficient electrocatalytic activity toward HER under acidic conditions with a low onset potential of 112 mV and a small Tafel slope of 44 mV per decade. The enhanced mechanism of electrocatalytic activity has been investigated in detail by controlling the elemental composition, electrical conductance and surface morphology of the 3D hybrid as well as Density Functional Theory (DFT) calculations. This demonstrates that the abundance of exposed active sulfur edge sites in the MoS(2) and nitrogen active functional moieties in N-RGO are synergistically responsible for the catalytic activity, whilst the distinguished and coherent interface in MoS(2)/N-RGO facilitates the electron transfer during electrocatalysis. Our study gives insights into the physical/chemical mechanism of enhanced HER performance in MoS(2)/N-RGO hybrids and illustrates how to design and construct a 3D hybrid to maximize the catalytic efficiency.
Funding
The work was supported by National Natural Science Foundation of China (NSFC Grant No. 21305008, 21475008, 21275017, 21127007), China Postdoctoral Special Foundation (NO. 11175039) and Ph.D. Programs Foundation of Ministry of Education of China (No. 11170197), the Fundamental Research Funds for the Central Universities (NO. 06199045) and the Chinese 1000 Elites program and USTB start-up fund.