Three dimensional Ni1+xFe2−xS4-graphene-2D-MoSe2 as an efficient material for supercapacitors

Abstract

A ternary Ni_1+xFe_2−xS₄-graphene-2D-MoSe₂ (Ni_1+xFe_2−xS₄-g-MoSe₂) nanocomposite was designed and fabricated through a facile two-step method. Well-dispersed Ni_1+xFe_2−xS₄ nanoparticles on graphene sheets were achieved using a hydrothermal method followed by coating with MoSe₂ nanosheets using in situ adsorption. The synergistic effect of the three components present in Ni_1+xFe_2−xS₄-g-MoSe₂ yielded enhanced electrochemical properties in terms of high specific capacitance reaching up to 2108 F g⁻¹ at a current density of 1 A g⁻¹, with capacity retention of 93.3% after 4000 cycles at the high charge–discharge current density of 5 A g⁻¹. These outstanding capacitance features were mainly attributed to the unique Ni_1+xFe_2−xS₄-g-MoSe₂ nanostructure, allowing easy access to the pseudocapacitive species and fast ion/electron transfer. Overall, the prepared 3D nanocomposite is promising as an electrode material for advanced supercapacitors.