Reconciled Nanoarchitecture with Overlapped 2 D Anatomy for High‐Energy Hybrid Supercapacitors

Abstract

A unique and novel, flower bouquet‐like, vanadium disulfide (VS2) nanosheet structure with very small prominent VS2 nanoparticles (10–25 nm) anchored on the surface of graphene nanosheets (VS2/G) was synthesized by a facile solvothermal method. The material showed superior electrochemical performance upon testing as a supercapacitor and achieved specific capacitance values of 211 and 135 F g−1 at current densities of 1 and 20 A g−1, respectively, with 97 % capacitance retention after 8000 cycles at 5 A g−1 with high coulombic efficiency. The material was used to fabricate a full‐cell hybrid supercapacitor (HSC), which showed a specific capacitance of 132 F g−1 at a current density of 1 A g−1 with remarkable cyclability up to 8000 cycles at 5 A g−1 and a loss of less than 1×10−4 F cycle−1. The HSC demonstrated an excellent energy density of 46.93 Wh kg−1 at a power density of 0.91 kW kg−1 and retained a high energy density of 23.11 Wh kg−1 even upon increasing the power density tenfold (9.40 kW kg−1). This unique material synthesized by a simple method is a very promising candidate for next‐generation energy‐storage technologies that can fill the gap between batteries and supercapacitor devices.

Synthesis of VS2/NiS Nanocomposites by In Situ Growing NiS Clusters on VS2 Ultrathin Nanoplates for High Performance Supercapacitors

“…The energy density reaches 69.58 Wh/kg at a power density of 874.9 W/kg, and when the power density is as high as 8752 W/kg, it still has an energy density of 25.98 Wh/kg. Such performances are better than the current vanadium‐based and nickel‐based supercapacitor devices reported in the literature [18,30,47–53] . The details are described in Table.…”

“…Such performances are better than the current vanadium-based and nickel-based supercapacitor devices reported in the literature. [18,30,[47][48][49][50][51][52][53] The details are described in Table. S2.…”