Fabrication of coral tentacle-like ZIF-67 derived NiCo-LDH/Ag nanowires on cotton fibers for wearable supercapacitor electrode materials

Abstract

Wearable flexible electronic devices suitable for the human body have promising prospects in areas such as health monitoring and smart communication. Therefore, rational design and fabrication of flexible electrode materials is of great importance for efficient energy storage in wearable electronic devices. In this work, a unique coral tentacle-like interconnected network structured nickel-cobalt layered double hydroxide/silver nanowires/cotton (NiCo-LDH/AgNWs/Cotton) flexible electrode material is developed by a facile three-step method: (ⅰ) AgNWs are adsorbed on cotton fibers to form a conductive network by dipping, (ⅱ) ZIF-67 precursors grow on AgNWs/Cotton by in-situ, and (ⅲ) ZIF-67 precursors are converted into interconnected NiCo-LDH nanosheets by hydrothermal. The NiCo-LDH/AgNWs/Cotton electrode material exhibits an ultra-high areal capacitance (823.9 mF cm−2 at 1 mA cm−2), and decent cycling performance (77.7 % after 1000 cycles). The assembled symmetrical supercapacitor exhibits 8.63 μWh cm−2 energy density at a power density of 0.26 mW cm−2. In addition, NiCo-LDH/AgNWs/Cotton electrode material also have excellent flexibility, mechanical properties, and electromagnetic shielding. This study achieves high-value utilization of cotton fibers and provides fresh ideas for the development of flexible supercapacitors.