Ultrathin NiAl layered double hydroxide-reduced graphene oxide composite nanosheets array with high battery performances for hybrid supercapacitor and hybrid battery

Abstract

Porous nanoarray architectures of electrode materials with rapid electron/ions migrations and highly accessible surface areas are eagerly desired for battery typed charge storage in various energy devices. Herein, NiAl layered double hydroxide-reduced graphene oxide composite (NA LDH-rGO) with ultrathin nanosheets array architecture onto Ni foam substrate was designed as battery electrode. The porous channels and interconnected walls with homogeneous embedding of reduced graphene oxide (rGO) enable the rapid and sufficient redox reaction of battery active NiAl layered double hydroxide (NA LDH) component, therefore, high areal capacity of 1.42 C cm−2 was yielded at 1 mA cm−2, and 0.88 C cm−2 was retained upon 20 folds increased current density by the representative NA LDH-rGO electrode. When used as battery electrode of hybrid supercapacitor (HSC), high energy density (Ecell, 0.22 mWh cm−2 at power density (Pcell) of 4.5 mW cm−2) and good cycling stability could be furnished simultaneously. In addition, the NA LDH-rGO electrode based Zn ions hybrid battery (HB) also offered high Ecell (0.48 mWh cm−2 at 1.9 mW cm−2), export voltage platform (over 1.7 V) and slow self-discharge rate, manifesting the feasibility of the NA LDH-rGO nanosheets array electrode for battery typed charge storage.