Rational Design of the CdS/Fe-MOF Hybrid for Enhanced Hydrogen Evolution Reaction Catalysis

Electrochemical water-splitting is a promising method for producing sustainable and eco-friendly hydrogen as an energy source. However, it is imperative to create a durable and exceptionally effective catalyst to guarantee an optimal process efficiency. Studies have shown that transition metal sulfides and metal-organic frameworks can be effective electrocatalysts for hydrogen production. Herein, the focus is on synthesizing and investigating hybrids composed of cadmium sulfide and MIL-101(Fe) (a metal-organic framework) for hydrogen evolution reaction (HER) in an alkaline environment. The results of the study indicate that these hybrids exhibit improved activity for HER compared to pure compounds. The optimized hybrid of CdS/MIL-101(Fe) (3:1) showed a small overpotential of 108 mV to achieve a 10 mA/cm²current density and a low Tafel value of 47 mV/dec in alkaline media. Additionally, it remained stable for 1000 cyclic voltammetry cycles and 24 h with only a minimum shift in performance. The synergistic interaction between the two functional materials is the probable cause for the improved activity of hybrids over pure compounds. The presence of MIL-101(Fe) provides increased active sites and porosity, while CdS enhances the electrical properties of the hybrid. These properties add up in the hybrid and result in an enhancement in activity. This development presents an appealing strategy for fabricating non-noble-metal electrocatalysts for hydrogen synthesis, thereby marking a noteworthy milestone in the pursuit of sustainable and eco-friendly energy production.