1T-2H Crx-MoS2 Ultrathin Nanosheets for Durable and Enhanced Hydrogen Evolution Reaction

MoS2-based materials for hydrogen evolution reaction (HER) were widely reported in recent years. However, the poor conductivity limited the application of MoS2. In this paper, we introduced the heteroatom Cr3+ into the MoS2 with different weight percent. The property for HER was largely enhanced, especially for the Cr0.06-MoS2. The overpotential of Cr0.06-MoS2 (0.20 V) was much lower than that of the undoped MoS2 (0.44 V) at current density of 10 mA cm–2. What’s more, the Cr0.06-MoS2 also has long time stability (>60 h) and almost 100% Faraday efficiency for water reduction. The enhanced HER activity was mostly due to the increased exposed active sites and shortened passway of electron transfer. For that the ultrathin nanosheets structure of Cr0.06-MoS2 displayed a larger BET surface area (165.52 m2 g–1) than the undoped MoS2 (130.31 m2 g–1). Besides, Cr0.06-MoS2 showed coexistence of 2H- and 1T-MoS2 phase after Cr3+ doping and resulted in much lower data of EIS (16.55 Ω) than the undoped MoS2 (51.85 Ω). ...