2D/2D heterostructures of nickel molybdate and MXene with strong coupled synergistic effect towards enhanced supercapacitor performance

Abstract Nickel molybdate is emerged as a promising electrode material in supercapacitors for its rich redox chemistry. However, its limited electrical and ionic conductivities keep it from achieving its full capacitance potential. Here, a facile pathway is reported to synthesize NiMoO 4 /Ti 3 C 2 T x nanosheets with interconnected porous construction, which may promote the electrolyte ion diffusion during reversible insertion/deinsertion processes, further improve its capacity. The fabricated NiMoO 4 /Ti 3 C 2 T x electrode exhibits a high specific capacity of 545.5 C g −1 (1364 F g −1 ) at a current density of 0.5 A g −1 alongside with attractive cycling stability, contributed to the strong synergistic effects between NiMoO 4 and Ti 3 C 2 T x . Furthermore, an asymmetric supercapacitor is fabricated by coupling NiMoO 4 /Ti 3 C 2 T x positive electrode with reduced graphene oxide hydrogel negative electrode, which demonstrates a broad potential window of 1.6 V, and an energy density of 33.76 W h kg −1 .