Nickel–Cobalt Layered Double Hydroxide Anchored Zinc Oxide Nanowires grown on Carbon Fiber Cloth for High-Performance Flexible Pseudocapacitive Energy Storage Devices

Abstract

Nickel-cobalt layered double hydroxide (Ni-Co LDH) nanoflakes–ZnO nanowires hybrid array has been directly synthesized on a carbon cloth substrate by a facile cost-effective two-step hydrothermal route. As electrode materials for flexible pseudocapacitors, Ni-Co LDH nanoflakes–ZnO nanowires hybrid array exhibits a significantly enhanced specific capacitance of 1927 Fg−1, which is a ∼1.8 time greater than pristine Ni-Co LDH nanoflakes. The synthesized Ni-Co LDH nanoflakes–ZnO nanowires hybrid array shows a maximum energy density of 45.55 Whkg−1 at a power density of 46.15 kWkg−1, which is 35% higher than the pristine Ni-Co LDH nanoflakes electrode. Moreover, Ni-Co LDH nanoflakes–ZnO nanowires hybrid array exhibit excellent excellent rate capability (80.3% capacity retention at 30 Ag−1) and cycling stability (only 3.98% loss after 3000 cycles), due to the significantly improved faradaic redox reaction.