Nanoarchitectonics with valorization of lignin-rich walnut shell into sulfur and nitrogen doped porous carbon functionalized with manganese oxide as an advanced electrode material for supercapacitor applications
Biomass and Bioenergy, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.biombioe.2026.109915
- Dergi Adı: Biomass and Bioenergy
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, Compendex, Environment Index, Geobase, INSPEC, Academic Search Ultimate (EBSCO), Engineering Source (EBSCO)
- Anahtar Kelimeler: Heteroatom doping, Lignin-derived porous carbon, MnOx-functionalized carbon, Supercapacitors, Walnut shell biomass
- Van Yüzüncü Yıl Üniversitesi Adresli: Evet
Özet
The conversion of lignocellulosic biomass into functional carbon materials through pyrolysis offers a sustainable strategy for developing advanced electrode materials for energy storage. In this study, lignin-rich walnut shell was employed as a renewable precursor for synthesizing manganese oxide-functionalized sulfur and nitrogen co-doped porous carbon. The composite was prepared through KOH-assisted pyrolysis, followed by heteroatom doping and potassium permanganate-mediated manganese oxide incorporation. The high lignin content promoted aromatic carbon condensation, resulting in a conductive carbon framework with interconnected micro/mesoporous structures. Sulfur and nitrogen co-doping, together with manganese oxide functionalization, enhanced the surface chemistry, electrical conductivity, and electrochemical activity of the porous carbon. Structural and electrochemical characterizations confirmed improved ion transport and charge-storage behavior. Electrochemical performance was investigated in acidic (1 M H2SO4), neutral (1 M Na2SO4), and alkaline (1 M KOH) electrolytes. The electrode exhibited the best performance in 1 M KOH owing to its higher ionic conductivity and faster ion diffusion. It delivered a specific capacitance of 278 F g−1 at 5 mV s−1 and retained 96 F g−1 at 100 mV s−1 from cyclic voltammetry measurements, while galvanostatic charge–discharge analysis yielded a maximum specific capacitance of 300 F g−1 at 2.0 A g−1. Furthermore, the electrode retained 93.6% of its initial capacitance after 10,000 charge–discharge cycles at 6.0 A g−1. These findings demonstrate the potential of lignin-rich walnut shell as a sustainable precursor for producing high-performance porous carbon electrodes for next-generation supercapacitors.