Synergistic tuning of WS3/rGO nanocomposites for optimized electrochemical hydrogen evolution

Abstract

This study explores the synthesis and characterization of a composite material comprising tungsten trisulfide (WS₃) and reduced graphene oxide (rGO), investigating the role of the variation of constituent materials and their role in optimizing the properties. A series of rGO/WS₃ nanocomposites has been synthesized and found that their properties can be precisely controlled by modifying the ratio of their constituent materials. The combination of these two materials, along with minor adjustments to the rGO proportions, resulted in improved structural, optical, and morphological properties, as well as enhanced electrocatalyst stability. The as-synthesized WS₃/rGO nanocomposites exhibited absorbance in both the UV and visible regions, with the band gap varying from 0.98 eV to 1.51 eV. Morphological analysis revealed that as the rGO content increased, the visibility of rGO nanosheets within the nanocomposites also proportionally increased. This synergy between WS₃ and rGO improves the overall electrochemical and optoelectronic performance, proving the material’s potential for advanced energy storage and conversion applications. Electrochemical characterization revealed the coexistence of both diffusive and capacitive behavior, which became more pronounced with increasing rGO content. The WS₃/rGO nanocomposites exhibited specific capacitance values ranging from 0.2 F/g to 0.05 F/g. Additionally, the decrease in specific capacitance with increasing scan rate suggests the presence of pseudocapacitive behavior. This dual functionality highlights the tunability of WS₃/rGO composites, offering a versatile approach for optimizing these materials for both energy storage and hydrogen production applications.

Graphical Abstract