Valorization of the waste biomass hazelnut shells for energy storage applications in the perspective of circular economy

Electric vehicles are becoming increasingly widespread as an effective alternative to internal combustion ones, since rising greenhouse gas emissions are causing significant climate change. However, electric vehicles still have unsolved energetic drawbacks, mainly related to the available batteries, including limited capacity performances within large driving distances, long charging times and high weight and size. For these reasons, hybrid energy storage systems, including batteries and supercapacitors, are becoming very attractive, whose efficiency mainly depends on the surface properties of the electrode. In this context, biomass represents a cheap and available carbon source, potentially exploitable for this application as electrode. In this work, two activated carbons have been synthesized by thermal pyrolysis of the waste biomass hazelnut shells, using KOH as activating agent. Up to now, preliminary cyclic voltammetry has shown their promising performances in comparison with the glassy carbon electrode, as the zero reference. This noteworthy result is due to the improved surface properties of the activated carbons. Further measurements of electrochemical impedance spectroscopy and galvanostatic charge-discharge are in progress, to complete the electrochemical characterization of such carbon materials.