Three-Dimensional Ternary rGO/VS2/WS2 Composite Hydrogel for Supercapacitor Applications

Abstract

In recent years, the development of lightweight electrode materials with excellent performance (energy density versus power density) has increased the number of uses for supercapacitors. Creating three-dimensional skeletal network structures with excellent specific capacitance and high energy density is still challenging. This study utilized a straightforward one-pot hydrothermal technique to construct a supercapacitor based on hydrogel 3D skeletal networks comprising rGO nanosheets with VS2/WS2 nanoparticles. The rGO appeared as flakes and layers, interconnected in nature, allowing for more ion transport pathways and a larger active surface area for EDLC performance. The heterostructured VS2 and WS2 nanoparticles were homogeneously anchored to the rGO layers and were porous in the hydrogel structure. The functioning rGO, rGO-VS2, and rGO-VS2-WS2 composite hydrogel electrodes were created without a binder on the Ni foam current collector using a hydraulic press. The rGO-VS2-WS2 composite hydrogel electrode showed excellent supercapacitor performance of 220 F g−1 at 1 A g−1 in 3M KOH electrolyte, which was more than those of the GO (158 F g−1) and rGO-VS2 (199 F g−1) hydrogels under similar conditions. Hydrogel electrodes made of rGO-VS2-WS2 had a power density of 355 Whkg−1 and a high energy density of 30.55 Whkg−1. It maintained a high energy density of up to 21.11 W/kg−1, even at a high power density of 3454 W/kg−1. Given the 3D shape and the excellent surface properties of rGO nanosheets with VS2 and WS2 nanoparticles as the hydrogel, this electrode has essential properties that make it a good choice for making high-performance capacitors.