Interface effect of C₃N₄-Ti₄O₇-MoS₂ composite toward enhanced electrocatalytic hydrogen evolution reaction

Electrocatalytic water splitting is one of the most prospective technology for hydrogen production. Molybdenum disulfide (MoS₂), as one of the most promising non-noble metal electrocatalysts, suffers from the disadvantages of limited catalytic sites and weak conductivity which urgently needs to be further optimized. Herein, the C₃N₄-Ti₄O₇-MoS₂ heterostructure is constructed through a simple hydrothermal strategy. The interfacial interaction between the active components leads to more exposed active sites, the redistribution of the surface charge, the optimization of the hydrogen adsorption kinetics and stability, which makes up the typical shortcomings of MoS₂. The results indicate that the interface effect endows C₃N₄-Ti₄O₇-MoS₂ catalyst with excellent electrocatalytic activity for hydrogen evolution reaction (HER). The current density of 50 mA/cm² for HER is obtained at the overpotential of 300 mV, with the lower Tafel slope (54 mV/dec) and stable catalytic activity over 33 h, which is much better than that of the pure MoS₂. This work indicates that the interface effect, as an effective strategy for rational design of MoS₂-based electrocatalysts, is crucial to the future development of catalytic hydrogen production.