Preparation of cellulose-based carbon nanofibers/NiCo2S4 composites for high-performance all-solid-state symmetric supercapacitors. (March 2022)

• Record Type: Journal Article
• Authors: Yuan, Chunshun; Zhang, Mengyun; Ni, Xuepeng; Li, Kunming; Liu, Chenglin; Chen, Huifang; Ju, Anqi
• Is Part Of: Journal of energy storage. Volume 47(2022)
• Publication Date: 2022-03
• Subjects: Cellulose -- NiCo2S4 nanosheets -- Supercapacitor -- Solvothermal method; Energy storage -- Periodicals; Energy storage -- Research -- Periodicals; 621.3126
• DOI: 10.1016/j.est.2021.103589
• Languages: English
• ISSNs: 2352-152X

Abstract

Highlights: A 3D freestanding cellulose-based carbon nanofiber (CCNFs) networks are prepared using cellulose as precursor. Both NiCo2S4 nanosheets and nanospheres are uniformly coated on C-CNFs through one-step solvothermal method. The C-CNFs/NiCo2 S4 nanosheets possess high specific capacitance of 1784 f g −1 at 1 a g −1 and good cyclic stability with 86.9% capacitance retention after 3000 cycles at 10 a g −1 . Four all-solid-state symmetric supercapacitors (ASSCs) in series can power a 'DHU' Logo consisted of 36 light emitting diodes. Abstract: Carbon fiber-based electrodes hold great potential application in flexible supercapacitors, however most of carbon fibers are fabricated by nonrenewable polyacrylonitrile. In this work, a 3D flexible cellulose-based carbon nanofiber (C-CNFs) networks were prepared by electrospinning and multi-step heat treatment using renewable cellulose as precursor; then NiCo2 S4 nanosheets and nanospheres were uniformly coated on C-CNFs through one-step solvothermal method to obtain flexible CCNFs/NiCo2 S4 electrodes for supercapacitor. Compared with the C-CNFs/NiCo2 S4 nanospheres, C-CNFs/NiCo2 S4 nanosheets achieve a higher specific capacitance of 1784 F g −1 at the current density of 1 A g −1 and possess lower resistance, which attributes to high specific surface area and low resistance of CCNFs/NiCo2 S4 nanosheets. Meanwhile, the C-CNFs/NiCo2 S4 nanosheets show excellent cyclic stability with 79.3% capacitance retention after 10, 000 cycles at the large current density of 10 A g −1 . Finally, all-solid-state symmetric supercapacitor (ASSC) assembled from C-CNFs/NiCo2 S4 nanosheets exhibits the large energy density of 85.53 Wh kg −1 at the power density of 1200 W kg −1 and good cyclic stability with 63.4% capacitance retention after 5000 cycles at the current density of 4 A g −1 . Four ASSCs in series can power a 'DHU' Logo consisted of 36 light emitting diodes, confirming the as-prepared flexible CNFs/NiCo2 S4 nanosheets have promising application in portable electronic devices and smart wearable devices. Graphical abstract: Image, graphical abstract