Highly porous nanocomposite of NiMoS4 nanosheets and reduced graphene oxide for energy storage application

Nguyen Van Hoa, Pham Anh Dat, Tran Ngoc Le, Nguyen Cong Minh, Nguyen Van Tang, Dao Thi Nga and Tran Quang Ngoc

Abstract

This study presents a high porous nanocomposite composed of reduced graphene oxide and NiMoS₄ (RGO/NiMoS₄) for supercapacitor electrode materials. The different morphologies of NiMoS₄ growth on RGO sheets were obtained via a facile one-step microwave-assisted method. The obtained material comprised NiMoS₄ nanoneedles of several nanometers in diameter, which are well attached to the surface of RGO nanosheets. The RGO/NiMoS₄ nanocomposite had a mesoporous structure, high specific surface area, and high electric conductivity. These excellent characteristics yield a fast electron and ion transport, and a large number of electroactive sites. The RGO/NiMoS₄ composite delivered a specific capacitance of 1273 F g⁻¹ at a current density of 1.0 A g⁻¹, high-rate capability of 71.3% retention from 1 to 6.5 A g⁻¹. Besides, an asymmetric supercapacitor device had a capacitance of 80 F g⁻¹ at a current density of 1.0 A g⁻¹ and an energy density of 82.5 Wh kg⁻¹ at a power density of 1000 W kg⁻¹ with an operating voltage of 1.6 V. Thus, the current RGO/NiMoS₄ nanocomposite has a great potential for energy storage application.