Electron injection induced phase transition of 2H to 1T MoS2 by cobalt and nickel substitutional doping

The semiconducting to metallic phase transition mechanism of MoS2 has gained immense attention due to the excellent electrocatalytic activity seen in catalysts and energy storage devices. However, the harsh conditions required for effective phase transition limits the applications of these materials. Compared with using flammable reductants, obtain metallic phase MoS2 by a chimie-douce route is widely expected. Herein, we synthesized high-1T phase-ratio MoS2 through a mild hydrothermal method with assistance of cobalt and nickel. The microstructure and composition of the Co,Ni-MoS2 material were detailed explored by cs-corrector transmission electron microscopy and synchrotron radiation spectrum. The process of phase transition was simulated by density functional theory calculation. We found that the phase transition was induced by electron injection during cobalt and nickel co-doping. Owing to abundant 1T-phase and smaller hydrogen adsorption/desorption energy, the prepared Co,Ni-MoS2 shows excellent hydrogen evolution reaction performance in alkaline solution.