WO3·0.33H2O/carbon quantum dots hybrid nanostructures for efficient electrochemical hydrogen evolution reaction

Low-cost electrocatalysts with good catalytic performance are highly desirable for the sustainable production of hydrogen in order to meet the growing global energy crisis. In this work, WO3·0.33H2O/casein-derived carbon quantum dots hybrid nanostructures were synthesized via hydrothermal synthesis route utilizing casein-derived carbon quantum dots and precursor salts of WO3, and its electrochemical performance as an HER electrocatalyst was investigated. XRD, FESEM, TEM, SAED, XPS, FTIR, and Raman analyses confirmed the structural and compositional features of the WO3·0.33H2O/carbon quantum dots hybrid nanostructures. The electrochemical studies showed an efficient HER activity for WO3·0.33H2O/carbon quantum dots hybrid nanostructure with a low overpotential of 197 mV and a small Tafel slope of 101 mV/dec. The synergic effect of the hydrated tungsten oxide and carbon dots enhanced the conductivity and number of accessible active sites, promoting better mass transport, which was responsible for better HER activity. This work presents a cost-effective and green strategy to develop WO3·0.33H2O/carbon quantum dots hybrid nanostructures as a suitable electrocatalyst for hydrogen production. [Display omitted] •Hydrothermal modification of WO3·0.33H2O nanostructures with casein-derived quantum dots•Enhanced hydrogen evolution for the modified WO3·0.33H2O/carbon quantum dots hybrid nanostructures•Enhanced HER activity is due to the synergy between the carbon dots and WO3·0.33H2O nanostructures.