Defective Amorphous Carbon‐Coated Carbon Nanotube‐Loaded Ruthenium Nanoparticles as Efficient Electrocatalysts for Hydrogen Production

Compared with hydrogen evolution reaction (HER) under acidic conditions, the kinetic steps of alkaline HER are more complex, which involves the adsorption and cleavage of water molecules. Defect and interface engineering are two important means to enhance basic HER. In order to prepare catalysts with high activity and stability under both acidic and basic conditions, a defective amorphous carbon loaded with Ru nanoparticles coaxially wrapped around a carbon nanotube (CNT) sponge network is presented. The presence of amorphous carbon can promote the uniform loading of Ru nanoparticles and limit the growth of Ru nanoparticles, and also the introduction of oxygen defects can regulate the electronic structure of the metal and improve its charge transport capacity, thus enhancing the catalytic performance. The catalyst CNT/C/Ru 0.37 wt% ‐700 prepared under optimized conditions exhibits excellent stability and activity. At a current density of 10 mA cm −2 , the overpotential of HER is as low as 38.3 and 36.2 mV under alkaline and acidic conditions, respectively, which is better than most reported Ru‐based catalysts. This study details innovative and feasible ideas for the design and preparation of loaded catalysts, which can contribute to the development of high‐performance electrochemical catalysts.