Synergistic enhancement of electrocatalytic hydrogen evolution by CoS2 nanoparticle-modified P-doped Ti3C2Tx heterostructure in acidic and alkaline media

•A two-step hydrothermal method was used to synthesize a CoS2/P-doped Ti3C2Tx catalyst.•The synergistic effect of CoS2 nanoparticles and phosphorus doped Ti3C2Tx enhanced the hydrogen evolution reaction.•CoS2/P-doped Ti3C2Tx hybrid catalyst exhibits a low overpotential of 130 and 180 mV in both acidic and alkaline electrolytes.•It exhibited excellent stability during continuous cyclic voltammetry. A facile method was developed to prepare a heterostructure of CoS2 nanoparticles and P-doped Ti3C2Tx for a high-performance electrocatalytic hydrogen evolution reaction. However, the performance of Ti3C2Tx is poor owing to its high overpotential. Small CoS2 nanoparticles grew well on the surface of the P-doped Ti3C2Tx, which further increased the active surface area for the adsorption of hydrogen ions. This hybrid structure exhibited high electrocatalytic activity with low overpotentials of 130 and 180 mV vs. RHE in acidic and alkaline electrolyte solutions, respectively, and excellent structural stability. The synergistic effect of the CoS2 nanoparticles and phosphorus doped Ti3C2Tx considerably enhanced the hydrogen evolution process (HER). The findings of this study suggest that the Ti3C2Tx nanosheets have excellent prospects for developing highly active electrocatalysts for water splitting.