Synergistic Effect in MoS2 Nanosheets–Biochar Nanocomposites with Enhanced Surface Area and Electrical Conductivity for Energy Storage Applications

Abstract

Layered molybdenum disulfide (MoS2), a transition metal dichalcogenide, shows distinct optical, electrical, and physical properties at a few-layer thickness. MoS2 nanosheets (NSs) widely explored for energy and environmental applications but have limitations with respect to their electrical conductivity and charge transfer characteristics due to their low surface area. These limitations can be overcome by combining MoS2 NSs with carbon-based materials like graphene, carbon nanotubes, and biochar, which can enhance the properties in a synergistic way. In this study, biochar (BC), a carbon-rich material prepared from vegetable biomass through low-temperature pyrolysis has been combined with bulk MoS2 in various ratios using an aqueous phase exfoliation method to form MoS2 NSs–biochar nanocomposites. The spectroscopic, structural, and morphological studies confirmed the synergistic interaction between MoS2 and BC, which is well reflected in the facile exfoliation process and the formation of few layered MoS2 NSs on the surface of the BC without any agglomeration. The electrochemical studies prove that incorporating biochar into MoS2 enhances the capacitive behavior and reduces the charge transfer resistance compared to pristine MoS2 NSs and pristine biochar. This study provides ample scope for the composite to be explored for energy storage applications, especially towards the development of electrode materials due to the synergistic effect between MoS2 NSs and biochar.