Unraveling the Factors Affecting the Electrochemical Performance of MoS2–Carbon Composite Catalysts for Hydrogen Evolution Reaction: Surface Defect and Electrical Resistance of Carbon Supports

In MoS2–carbon composite catalysts for hydrogen evolution reaction (HER), the carbon materials generally act as supports to enhance the catalytic activity of MoS2 nanosheets. The carbon support provides a large surface area for increasing the MoS2 edge site density, and its physical structure can affect the electron transport rate in the composite catalysts. However, despite the importance of the carbon materials, direct observation of the effects of the physical properties of the carbon supports on the HER activity of MoS2–carbon composite catalysts has been hardly reported. In this work, we conduct an experimental model study to find the fundamental and important understanding of the correlation between the structural characteristics of carbon supports and the HER performance of MoS2–carbon composite catalysts using surface-modified graphitic carbon shell (GCS)-encapsulated SiO2 nanowires (GCS@SiO2 NWs) as support materials for MoS2 nanosheets. The surface defect density and the electrical resistance of...