Hydrogen evolution reaction efficiency of carbon nanohorn incorporating molybdenum sulfide and polydopamine/palladium nanoparticles

The involvement of carbon nanohorn (CNH) in molybdenum sulfide (MoS2) and polydopamine (PDA)/palladium nanoparticles (Pd NPs) was studied for the hydrogen evolution reaction (HER) efficiency. In this research, the in-situ hydrothermal and PDA-assisted chemical reaction routes were adopted to synthesize MoS2/CNH and PDA-Pd/CNH nanocomposites. The electrochemical studies confirmed the HER activity of PDA-Pd/CNH-modified electrode superior to that of MoS2/CNH-modified electrode. The coating thickness of PDA was optimized towards high HER efficiency. The enhancement of HER cathodic current density was due to the strong interaction between CNH and Pd NPs. The thin coating by PDA on Pd/CNH nanocomposites maintained the excellent stability and the durability during the HER. Thus, CNH is one of the hopeful carbon materials to enhance the cathodic current density for HER.