Enhanced faradic activity by construction of p-n junction within reduced graphene oxide@cobalt nickel sulfide@nickle cobalt layered double hydroxide composite electrode for charge storage in hybrid supercapacitor

The intrinsic faradic reactivity is the uppermost factor determining the charge storage capability of battery material, the construction of p-n junction composing of different faradic components is a rational tactics to enhance the faradic activity. Herein, a reduced graphene [email protected] nickle [email protected] cobalt layered double hydroxide composite ([email protected]2S4@NiCo LDH) with p-n junction structure is designed by deposition of n-type nickle cobalt layered double hydroxide (NiCo LDH) around p-type reduced graphene [email protected] nickle sulfide ([email protected]2S4), the charge redistribution across the p-n junction enables enhanced faradic activities of both components and further the overall charge storage capacity of the resultant [email protected]2S4@NiCo LDH battery electrode. As expected, the [email protected]2S4@NiCo LDH electrode can deliver high specific capacity (Cs, 1310 ± 26 C g−1 at 1 A g−1) and good cycleability (77% Cs maintaining ratio undergoes 5000 charge-discharge cycles). Furthermore, the hybrid supercapacitor (HSC) based on the [email protected]2S4@NiCo LDH p-n junction battery electrode exports high energy density (Ecell, 57.4 Wh kg−1 at 323 W kg−1) and good durability, showing the prospect of faradic p-n junction composite in battery typed energy storage.