Dense organic molecules/graphene network anodes with superior volumetric and areal performance for asymmetric supercapacitors. Issue 1 (10th December 2019)

• Record Type: Journal Article
• Authors: Zhang, Lina; Han, Daliang; Tao, Ying; Cui, Changjun; Deng, Yaqian; Dong, Ximan; Lv, Wei; Lin, Zifeng; Wu, Shichao; Weng, Zhe; Yang, Quan-Hong
• Is Part Of: Journal of materials chemistry. Volume 8:Issue 1(2020)
• Page Start: 461
• Page End: 469
• Publication Date: 2019-12-10
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c9ta09941g
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : A dense but unimpeded electron/ion conductive AQS/graphene network is designed to construct high-volumetric/areal-capacitance thick electrodes. Abstract : Volumetric and areal capacitance are as important as gravimetric capacitance for small energy storage devices. However, achieving both a high volumetric and a high areal capacitance is still a big challenge. Here we report a dense redox organic molecules/graphene network, in which highly redox active sodium anthraquinone-2-sulfonate (AQS) molecules are anchored on interconnected and highly conductive graphene sheets by noncovalent π–π interactions to form high-performance supercapacitors (SCs). The AQS/graphene (AQS/G) has a high volumetric specific capacitance of up to 650 F cm −3 and an excellent rate capability (422 F cm −3 even at 30 A g −1 ), as well as a good cycling stability. A maximum areal specific capacitance of 13.3 F cm −2 is achieved at a high mass loading of 32 mg cm −2 (200 μm in thickness), which is amongst the highest values recorded for organic-based materials for SCs. An asymmetric SC constructed with AQS/G and RuO2 /graphene delivers a maximum volumetric energy density of 44 W h L −1 . This outstanding performance is attributed to the excellent electron conduction and ion transport provided by the dense but interconnected graphene network. This work suggests a new way for organic-based high-performance electrode materials to be used in electrochemical energy storage devices.