Scalable synthesis of γ-Fe2O3–based composite films as freestanding negative electrodes with ultra-high areal capacitances for high-performance asymmetric supercapacitors

Jyothibasu, Jincy Parayangattil; Wang, Ruei-Hong; Ong, Kenneth; Ong, Juping Hillary Lin; Lee, Rong-Ho

Scalable synthesis of γ-Fe2O3–based composite films as freestanding negative electrodes with ultra-high areal capacitances for high-performance asymmetric supercapacitors

2022

Jyothibasu, Jincy Parayangattil | Wang, Ruei-Hong | Ong, Kenneth | Ong, Juping Hillary Lin | Lee, Rong-Ho

This paper reports a simple, cost-effective, and environmentally friendly procedure for the synthesis of cellulose/functionalized carbon nanotube (f-CNT)/Fe₂O₃ (CCF) composite films and their performance as freestanding negative electrodes in supercapacitors. A facile chemical precipitation process was performed at room temperature within a short reaction time without requiring any of the special processing conditions used in the conventional hydrothermal synthesis, making it the most cost-efficient method for the bulk-scale production of sustainable supercapacitors. The binder-free negative electrode with ultra-high active material loading exhibited outstanding areal (9107.1 mF cm–²) and volumetric (314 F cm–³) capacitances, which were much greater than the values reported previously in the literature for negative electrodes. Moreover, an asymmetric supercapacitor cell featuring cellulose/f-CNT/MnO₂ (CCM) and CCF as its positive and negative electrodes, respectively, achieved superior electrochemical performances. Therefore, on account of the economic and environmental superiority of this method and its bulk scalability, this paper provides a simple, eco-friendly, and cost-effective approach for the development of sustainable supercapacitors for practical use.

Показать больше [+]