Vanja Gujaničić^1,2, Danica Bajić^3,2,  Mirjana Krstović^3,2, Marija Baltić⁴, Aleksandar Knežević⁵, Radovan Karkalić³, Milica Košević^6,*

¹ Technical Test Center, Vojvode Stepe 445, 11000 Belgrade, Serbia,

² University of Defence, Military Academy, Veljka Lukića Kurjaka 33, 11040 Belgrade, Serbia

³Military Technical Institute, Ratka Resanovića 1, 11030 Belgrade, Serbia

⁴ University of Belgrade, Faculty of Mechanical Engineering, Kraljice Marije 16, 11120 Belgrade, Serbia

⁵ University of Belgrade, Faculty of Biology, Studentski trg 16, 11000 Belgrade, Serbia

⁶ University of Belgrade, Institute of Chemistry, Technology and Metallurgy – National Institute of the Republic of Serbia, Njegoševa 12, 11000 Belgrade, Serbia

^*milica.kosevic@ihtm.bg.ac.rs

https://doi.org/10.65614/uisk_yucorr.2025.26.ch26

Abstract

The growing demand for sustainable energy storage solutions drives the search for eco-friendly and low-cost electrode materials for supercapacitors. This study presents a sustainable approach for converting discarded hazelnut bark-based biocomposite into activated carbon (AC). The biocomposite was chemically activated with KOH at a mass ratio of 1:3. The mixture was then thermally treated under a nitrogen atmosphere in two stages: initially heated at 2 °C/ min to 500 °C and held for 1 h, followed by heating at 5 °C min⁻¹ to 800 °C with an additional 1 h retention time.  Electrochemical performance was investigated by cyclic voltammetry (CV) at various scan rates in 0.5 M H₂SO₄. The CV curves show a nearly rectangular shape, indicating that the charge storage mechanism is predominantly governed by electric double-layer capacitance. These findings demonstrate that hazelnut bark-based biocomposite represents a sustainable and efficient precursor for producing high-performance activated carbons, offering a promising alternative to conventional electrode materials in supercapacitors and contributing to environmentally responsible energy storage technologies.

Keywords: Biomass-derived carbon; porous carbon; KOH activation

Izvod

Rastuća potražnja za održivim rešenjima za skladištenje energije podstiče razvoj ekološki prihvatljivih i ekonomičnih elektrodnih  materijala za superkontenzatore. U ovom radu je prikazan održiv pristup za konverziju odbačenog biokompozita na bazi kore lešnika u aktivirani ugljenik (AC). Biokompozit je hemijski aktiviran pomoću KOH u masenom odnosu 1:3, a zatim termički tretiran u atmosferi azota u dva koraka: u prvom koraku je zagrevan brzinom od 2 °C/min do 500 °C uz zadržavanje od 1 h, a potom zagrevan brzinom od 5 °C/min do 800 °C uz dodatno zadržavanje od 1 h. Elektrohemijska svojstva su ispitivana metodom ciklične voltametrije (CV) pri različitim brzinama skeniranja u rastvoru 0,5 M H₂SO₄. CV krive pokazuju približno pravougaoni oblik, što ukazuje na to da je mehanizam skladištenja naelektrisanja pretežno zasnovan na kapacitivnosti dvojnog sloja. Ovi nalazi pokazuju da biokompozit na bazi kore lešnika predstavlja održiv i efikasan prekurzor za dobijanje aktiviranih ugljenika, koji mogu služiti kao obećavajuća alternativa konvencionalnim elektrodnim materijalima u superkondenzatorima i doprineti razvoju ekološki odgovorne tehnologije skladištenja energije.

Ključne reči: ugljenik dobijen iz biomase; porozni ugljenik; aktivacija sa KOH