Abstract
Carbon-based materials are manufactured as high-performance electrodes using biomass waste in the renewable energy storage field. Herein, four types of hierarchical porous activated carbon using hibiscus sabdariffa fruits (HBFs) as a low-cost biomass precursor are synthesized through carbonization and activation. NH4Cl is used as a chemical blowing agent to form carbon nanosheets, which are the first types of hibiscus sabdariffa fruit-based carbon (HBFC-1) sample, and KOH also forms a significant bond in the activation process. The prepared HBFC-1 is chosen to manufacture the symmetric supercapacitor due to its rough surface and high surface area (1720.46 m2 g−1), making it show a high specific capacity of 194.50 F g−1 at a current density of 0.5 A g−1 in a three-electrode system. Moreover, the HBFC-1 based symmetric supercapacitor devices display a high energy density of 13.10 W h kg−1 at a power density of 225.00 W kg−1, and a high specific capacity of 29 F g−1 at 0.5 A g−1. Additionally, excellent cycle life is observed (about 96% of capacitance retained after 5000 cycles). Therefore, biomass waste, especially hibiscus sabdariffa fruit based porous carbon, can be used as the electrode for high-performance supercapacitor devices.
Highlights
With the rapid social and economic development, the energy crisis and environmental problems have made it essential to develop eco-friendly and low-cost energy sources.[1,2] renewable energy sources with high power/energy densities have much inspired widespread research interests to develop highperformance energy storage devices.[3]
The schematic illustration for the preparation of hibiscus sabdariffa fruits derived activated carbon (HBFC)-1 is described in Scheme 1
The KOH used as an activator can enhance the HBFCs (HBFC-1, HBFC-2) pore size, while the NH4Cl is a chemical-blowing agent for the preparation of HBFCs which can signi cantly enhance their pore volume and provide effective nitrogen doping in (HBFC-1 and HBFC-2) materials
Summary
With the rapid social and economic development, the energy crisis and environmental problems have made it essential to develop eco-friendly and low-cost energy sources.[1,2] renewable energy sources with high power/energy densities have much inspired widespread research interests to develop highperformance energy storage devices.[3]. Selecting the convenient heteroatom-containing biomass precursor is very important, and the effect of the pore structure plays an important role in amelioration electrochemical performance in aqueous electrolytes.[10] The properties of the biomassderived activated porous carbons, including surface chemistry, are affected by the quality of the material and porosity, pore frame, pore size distribution, and the activation conditions.[11,12] To utilize porous carbons in energy storage equipment, the optimizing their structural characteristics is of great signi cance to practical applications For their use as electrodes in supercapacitors, these materials need to possess a high speci c surface area simultaneously with a suitable pore size distribution that combines narrow micropores appropriate for the accommodation of ions with super pores that favor ion transport and serve for storing electrolyte.[13] There are two activation techniques for the derivation of activated carbons from biomass precursor's physical and chemical activations. The porous activated carbons (HBFC-1) can be used as high-performance symmetric supercapacitor electrodes
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
