Screen-printable films of graphene/CoS2/Ni3S4 composites for the fabrication of flexible and arbitrary-shaped all-solid-state hybrid supercapacitors

• Published in: Carbon (New York) Vol. 146; pp. 557 - 567
• Main Authors: Jiang, Degang, Liang, Hui, Yang, Wenrong, Liu, Yan, Cao, Xueying, Zhang, Jingmin, Li, Chenwei, Liu, Jingquan, Gooding, J. Justin
• Format: Journal Article
• Language: English
• Published: New York Elsevier Ltd 01.05.2019; Elsevier BV
• Subjects: active sites; Batteries; capacitance; Cobalt sulfide; Cycles; electrochemistry; Electrodes; Electronic devices; electronic equipment; Electronics; energy density; Flux density; Graphene; graphene oxide; nanosheets; Production methods; Substrates; Supercapacitors; Vulcanization; Wearable computers; Wearable technology
• ISSN: 0008-6223; 1873-3891
• DOI: 10.1016/j.carbon.2019.02.045

Supercapacitors are attracting increasing research interest because they are expected to achieve battery-level energy density while having a long calendar life and a short charging time. However, the development of large-scale and cost-reasonable production methods for flexible, wearable and arbitrary-shaped supercapacitor devices still faces enormous challenges. Herein, a 3D-network, porous graphene/CoS2/Ni3S4 (G/CoS2/Ni3S4) composite electrode has been designed and synthesized through a combination of solvothermal and vulcanization methods. By combining the networked CoS2/Ni3S4 nanoflakes with reduced graphene oxide (RGO) nanosheets, the as-prepared composite electrode exhibits good conductivity, a high density of electrochemically active sites and good cycling stability. The result is a high specific capacitance of 1739 F g−1 at a current density of 0.5 A g−1. Significantly, the arbitrary-shaped G/CoS2/Ni3S4||GF hybrid supercapacitor devices can be printed directly on different substrates, which favorably combine mechanical flexibility, good cycling performance and high energy density. This methodology may be feasible to prepare fully-printable and wearable supercapacitors, and other electronic devices in large scale, thereby holding enormous potential for wearable technologies. [Display omitted]