Valorizing High-Fraction Bio-Oil to Prepare 3d Interconnected Porous Carbon with Efficient Pore Utilization for Supercapacitor Applications

Heavy-fraction bio-oil (HB) is an underused product of biomass pyrolysis due to its difficulty in direct use or efficient refinery, but it is a potential carbon precursor to prepare porous carbon for energy storage. The fluid HB with structural flexibility and miscibility is desirable to fabricate tailored carbon structure. In this work, we developed an in-situ activation method to convert HB into carbon-based electrode for supercapacitor applications. HB was pre-mixed with KOH activator in aqueous phase and then formed a solid composite, thus the inserted KOH could act as both activator and template agent for pore generation. The resultant porous carbon exhibits a 3D interconnected framework with micropore dominant structure. Benefiting from the structural features, the moderate surface area contributes a high capacitance indicating the excellent pore utilization efficiency, which is superior to most activated carbons and the commercial electrode material YP-50F. Furthermore, the porous carbon shows outstanding energy density, power density and cycling stability in both aqueous and organic electrolyte, indicating a promising application potential. The valorization of HB not only provides a cost-effective electrode material for energy storage, but also promotes the comprehensive utilization from biomass pyrolysis technology.