Towards flexible and wearable supercapacitors: A hierarchical approach in material design
Anna Batlle1, Llorenç Servera1, 2, Aïda Varea1, Albert Cirera1*
1Department of Engineering: Electronics. IN2UB, Universitat de Barcelona, Martí i Franquès 1, Barcelona, 08028, Spain
2EUSS: Escola Universitaria Salesiana de Sarria, Passeig de Sant Joan Bosco, 74, Barcelona, 08017, Spain
Adv. Mater. Lett., 2017, 8 (12), pp 1145-1149
Publication Date (Web): Sep 08, 2017
Copyright © 2019 VBRI Press
Wearable devices requires from macroscopic mechanical properties laying in macro-scale in comparison with chemical processes that requires from material design in the nanoscale. Besides, such reactions and phenomena involves charge transfer, and therefore a charge transducer in mean scale is required. In this paper we propose a flexible and wearable supercapacitor that takes advantage of a conductive fabric current collector that is coated by electrospray with MnO2-decorated carbon nanofibers (CNF). The results point out that a high capacitance is obtained due to the pseudocapacitive reactions in MnO2; moreover, the long and conductive structure of CNF allow transferring charge to conductive fabric, keeping a low equivalent serial resistance (ESR). The results indicate a specific capacitance on fabric collector of (226.40 ± 0.3) F/g, about 10 times higher than on aluminum foil collector, with a similar ESR which indicates a suitable way to wearable devices. The proposed technique is scalable, and can be easily applied in the industry.
Supercapacitor, fabric, CNF, MnO2, electrospray.