Shell K.M., Maddipudi B.K., Amar V., Thakkar A., Shende R.V., Kumar S., Gupta R.B.
Virginia Commonwealth University, US
Keywords: corn-stover, hydrothermal liquefaction, supercapacitors, thermal activation, unhydrolyzed solids
Use of biomass is an emerging and promising alternative to produce carbon electrodes for supercapacitors. Lignin-rich unhydrolyzed solids (UHS) obtained from alkaline pretreatment and enzymatic hydrolysis of corn stover were valorized into biochar via hydrothermally liquefaction (HTL) under catalytic environment. As obtained biochar was thermally activated, pH neutralized and later converted to biocarbon using a facile one-step thermal activation process. Activation/carbonization was carried out in a tubular furnace at 850 °C (815 °C actual) for 3 hours at a heating rate of 5 °C min-1 under argon flow. Electrode ink was formulated by combining 80 wt.% biocarbon, 10 wt.% high conducting carbon black (Super P), and 10 wt.% polytetrafluoroethylene (PTFE, 60 wt.% in H2O), and a reserved amount of H2O. Slurry was applied to Ni foam, dried, pressed, then templated and insulated with chemical resistant epoxy. Electrochemical measurements were conducted using a potentiostat, where specific capacitances determined via cyclic voltammetry (CV) and the results obtained were compared to the supercapacitors fabricated from biochar derived at non- catalytic HTL environment. The electrodes produced were well suited for use in supercapacitors.
Journal: TechConnect Briefs
Volume: TechConnect Briefs 2021
Published: October 18, 2021
Pages: 219 - 223
Industry sector: Energy & Sustainability
Topics: Catalysis, Energy Storage
ISBN: 978-0-578-99550-2