Synthesis of highly efficient bifunctional Nd2S3-MoSe2 heterostructure electrocatalyst for overall water-splitting

Water splitting technology is crucial for the commercial generation of hydrogen and evolution of oxygen. The development of rationally designed and efficient bifunctional nanostructure catalysts has thus become a necessity. Herein, we report a novel heterostructure Nd2S3-MoSe2 synthesized via a hydrothermal method as a promising alternative material for bifunctional overall water-splitting. The results of physical characterization confirmed the crystalline phases, desirable functionality, and structural distortion, forming a new multiphase interface for excellent electrochemical activity. Additionally, the X-ray photoelectron spectroscopy (XPS) examination demonstrated desirable electronic structure and the synergistic interaction between Nd2S3 and MoSe2, with the XPS analysis further promoting the electron transfer from MoSe2 to Nd2S3 toward a more efficient overall water-splitting configuration. Compared to the individual oxygen evolution/hydrogen evolution reactions (OER/HER), the bifunctional composite exhibits remarkable overall activity with low overpotential 215 mV (OER) and 190 mV (HER) to deliver 10 mA/cm2 current density in a 1 M KOH solution. This enhanced performance also facilitated the electroactive surface area and reduced the impedance compared to pure ones. Notably, when used as both anode and cathode in two electrodes alkaline water electrolyzer, Nd2S3-MoSe2 demonstrated a fairly low cell voltage (1.45 V@ 10 mA/cm2 and 1.88 V@50 mA/cm2) and impressive durability for 135 h, making it sustainable and highly promising for potential applications.