Upcycling waste natural gels: Their capacitive behavior in supercapacitors designed by polypyrrole and polypyrrole-Mn oxide electrodes
MATERIALS SCIENCE AND ENGINEERING B-ADVANCED FUNCTIONAL SOLID-STATE MATERIALS, cilt.332, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 332
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.mseb.2026.119631
- Dergi Adı: MATERIALS SCIENCE AND ENGINEERING B-ADVANCED FUNCTIONAL SOLID-STATE MATERIALS
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Chimica, Compendex, INSPEC, Academic Search Ultimate (EBSCO), Engineering Source (EBSCO)
- Bursa Uludağ Üniversitesi Adresli: Evet
Özet
Natural biopolymers of aloe vera (AV) and quince seed (QS) were extracted using a simple method in our laboratory. Their conductivity and pH were altered with KCl and NaCl salts. Polypyrrole (PPy) and PPy-Mn oxide (PPy-MnOx) electrodes were electrodeposited on pencil graphite (G). The highest specific capacitance of G/PPy and G/PPy-MnOx electrodes was 117.9 F/g and 103.1 F/g at a scan rate of 5 mV/s in AV-KCl gel. The G/PPyMnOx electrode had a retention of 127% for the 800th cycle and 104% for the 2000th cycle. The contributions from double-layer (DL) and pseudocapacitance (PC) were analyzed using Dunn's and Trasatti's methods. An asymmetrical supercapacitor, G/PPy//AV-KCl//PPy-MnOx/G, and a symmetrical supercapacitor, G/PPyMnOx//QS-NaCl//PPy-MnOx/G, were assembled. A positive potential up to 3.5 V was applied, and leaf-like curves by cyclic voltammetry (CV) were obtained. The specific capacitance of G/PPy//AV-KCl//PPy-MnOx/G reached 165.6 F/g in the narrowest potential window of 1.4 V, and 33.9 F/g in the widest window (3.5 V). This supercapacitor has a superior energy density of 12 Wh/kg and a power density of 70 W/kg. The promising results highlight an example of up-cycling, transforming waste material into a part of a globally and highly demanded energy storage device.