Fabrication and design of new redox active azure A/3D graphene aerogel and conductive trypan blue–nickel MOF nanosheet array electrodes for an asymmetric supercapattery

Abstract

Great efforts have been made to design and fabricate low-cost, high efficiency advanced electrode materials for energy storage devices such as batteries and high-performance supercapacitors. Choosing organic and redox active species that increase the faradaic charge storage of electrode systems has thus become a challenge to increase energy density and conductivity. To this aim, herein, azure A/3D graphene aerogel (Az–GA), and trypan (Try) blue–nickel metal–organic framework (Try–Ni-MOF) nanosheet array redox active electrodes are fabricated via a hydrothermal method and used in an asymmetric supercapattery. Az links to 3D GA via π–π interactions to form an anode. A nickel chloride hexahydrate array combines with Try as a MOF to form a cathode. These redox active materials increase the faradaic charge storage of the system. The as-prepared asymmetric device shows a high specific capacitance of 319 F g⁻¹ at 1 A g⁻¹, a specific energy of 66.55 W h kg⁻¹, a specific power of up to 4.45 kW kg⁻¹, and a higher capacity retention of 92.12% after 5000 charge–discharge cycles at 10 A g⁻¹. This device exhibits a broad potential window of 1.60 V and represents a promising strategy toward safe and sustainable energy storage devices.