Energy- and cost-efficient CaCO3-assisted nanoarchitectonics of recycled wheat flour-derived carbon matrix decorated with MnO2 nanoparticles for high-performance supercapacitor

• Published in: Journal of energy storage Vol. 72; p. 108355
• Main Authors: Du, Xiaoyi, Hou, Chuanxin, Kimura, Hideo, Xie, Xiubo, Jiang, Huiyu, Sun, Xueqin, Yang, Xiaoyang, Zhang, Yuping, Du, Wei
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 20.11.2023
• Subjects: MnO2; Supercapacitor; Template method; Wheat flour-derived carbon; Template method; MnO2; Supercapacitor; Wheat flour-derived carbon
• ISSN: 2352-152X; 2352-1538
• DOI: 10.1016/j.est.2023.108355

Production cost, electrochemical performance and service life are the key factors in the design and manufacture of electrode materials for supercapacitors. The problems of low capacitance and structure instability can be solved by constructing composites of metal oxide and carbon matrix. Herein, low-cost and high-stability carbon@MnO2 composite materials, where the three-dimensional (3D) porous wheat flour-derived carbon (WFC) matrix originated from expired wheat flour, which decorated with MnO2 nanoparticles (WFC@MnO2), was synthesized via an energy- and cost-efficient CaCO3-assisted synthesis route. The prepared electrodes manifest 197 F g−1 at 1.0 A g−1 and outstanding capacitance retention of 100 % after 5000 cycles, substantiating the synergistic effect of the high capacitance of MnO2 and excellent capacity retention of WFC. Furthermore, the symmetric supercapacitor assembled with WFC@MnO2 as positive and negative electrodes deliver an excellent electrochemical performance and achieve energy density and power density maxima of 17.1 Wh kg−1 and 11,000 W kg−1, and a capacitance retention of 95 % after 5000 cycles. This strategy provides an effective biological fermentation strategy for achieving high-performance and low-cost 3D porous WFC@MnO2 composites, improving the utilization of waste biomass and promoting environmental protection. WFC@MnO2 composite material was synthesized via a simple fermentation and CaCO3-assisted template method, which exhibits excellent electrochemical performance. [Display omitted] •3D porous CaCO3-assisted wheat flour derived WFC@MnO2 composite was synthesized.•Make full use of expired wheat flour to realize cost saving and waste utilization.•WFC@MnO2 retained 100 % initial capacity after 5000 cycles.•The equipped symmetric supercapacitor device can power the light for a long time.