A review of biochar production and its employment in synthesizing carbon-based materials for supercapacitors

Biomass waste treatment via thermochemical processes such as pyrolysis , hydrothermal carbonization , flash carbonization, and gasification results in biochar formation. These various pathways of biochar production provide an eco-friendly basis for obtaining further carbon-based materials. Carbon materials such as porous carbon material, doped biochar, carbon nanotubes , graphene, and carbon quantum dots can be prepared via physical and chemical modification of biochar. Furthermore, the biochar can be treated or processed under varying conditions regarding the physiochemical properties of these carbon-based materials. Their ability to store charge and its utilization as electrode materials for supercapacitors are summarized. The challenges and future perspectives associated with preparing these materials are also discussed in this review.