Large-scale single-step synthesis of wrinkled N-S doped 3D graphene like nanosheets from Tender palm shoots for high energy density supercapacitors

Herein, we present a simple, large-scale and low-cost process to develop hierarchically porous NeS co-doped 3D wrinkled graphene like nanosheets (3D H-GNS) from carbonization of biomass Tender palm shoots and NaHCO3. Non-corrosive and non-toxic Na2CO3 acts as a reaction mean to control the activation process, developing 3D H-GNS with a high specific surface area of 2095 m(2) g(-1). A 3D H-GNS-900 electrode exhibits a high specific capacitance of 529 F g-1 (1.5 A g(-1)) and 330 F g(-1) (1 A g(-1)) in1MH(2)SO(4) for 3-electrode and 2-electrode systems respectively. Further, a longer cycle life with 93% capacitance retention over 10,000 cycles at 5 A g(-1) is realized. Also, we are successful in fabricating biocompatible solid-state flexible supercapacitor device with 3D H-GNS-900 electrodes in organic electrolyte with 3 V voltage range, demonstrating to run a toy fan and lightning a LED for 15 min after charging for 60 s. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

The study presents a simple, large-scale, and cost-effective method to develop hierarchically porous 3D H-GNS with high specific surface area, showing superior performance in the field of supercapacitors. In addition, a biocompatible solid-state flexible supercapacitor device was successfully fabricated and demonstrated for applications in organic electrolytes.