2D heterostructure comprised of Ni3S2/d-Ti3C2 supported on Ni foam as binder-free electrode for hybrid supercapacitor

2D materials and their composites are promising energy storage candidates. In this work, 2D horizontal heterostructure comprised of Ni 3 S 2 /delaminated-Ti 3 C 2 , denoted as Ni 3 S 2 /d-Ti 3 C 2 , supported on Ni foam is prepared by a two-step method and used as binder free electrode for hybrid supercapacitor . The as-obtained composites are characterized by X-ray diffraction analysis, scanning electron microscope, transmission electron microscope and X-ray photoelectron spectroscopy. The electrochemical properties of Ni 3 S 2 /d-Ti 3 C 2 on Ni foam (denoted as Ni 3 S 2 /d-Ti 3 C 2 /NF) are studied using cyclic voltammetry , galvanostatic charge-discharge analysis and electrochemical impedance spectroscopy . It is found that the Ni 3 S 2 /d-Ti 3 C 2 /NF electrode exhibits superior capacitive performance with specific capacity of 2204 F g −1 at a constant current density of 1 A g −1 . A hybrid supercapacitor is fabricated by using Ni 3 S 2 /d-Ti 3 C 2 /NF electrode as positive electrode, active carbon (AC) coated on Ni foam as negative electrode and KOH aqueous solution as electrolyte. The Ni 3 S 2 /d-Ti 3 C 2 /NF//AC hybrid supercapacitor exhibits a maximum energy density of 23.6 W h kg −1 and a maximum power density of 4004.4 W kg −1 . The results supply new strategy for constructing MXene-based 2D horizontal heterostructure, and suggest that Ni 3 S 2 /d-Ti 3 C 2 /NF composite as a binder free electrode is an ideal candidate for supercapacitor applications.