Nanocomposite of MoS _2 on ordered mesoporous carbon nanospheres: A highly active catalyst for electrochemical hydrogen evolution

摘要

An efficient electrocatalyst for hydrogen evolution has been developed based upon in situ reduction of MoS _2 on ordered mesoporous carbon nanospheres (MoS _2/MCNs). The properties of MoS _2/MCNs were characterised by scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy. Polarisation curves and electrochemical impedance measurements were obtained for MoS _2/MCNs modified glassy carbon electrodes. The MoS _2/MCNs exhibit high catalytic activity for hydrogen evolution with a low overpotential and a very high current density. A theory outlining the origins of the Tafel slope for a Volmer-Heyrovsky (rate determining step) mechanism of hydrogen evolution at MoS _2 catalytic edge sites is presented.