Filmes nanoestruturados contendo óxido de grafeno reduzido e óxido de tungstênio: estudo em dispositivos superca

Abstract

The research dedicated to the development of new nanocomposites plays a crucial role in the quest for supercapacitors with higher energy storage capacity. In this study, strategies employing nanostructured films through the Layer-by-Layer (LbL) self-assembly technique were employed. These films consist of the incorporation of tungsten oxide (WO3) and reduced graphene oxide (rGO) nanostructures combined with Poly(amidoamine) (PAMAM) on a glass substrate coated with ITO (indium tin oxide) for supercapacitor study. The growth of the films was monitored by (UV-VIS) spectroscopy, while images from atomic force microscopy (AFM) confirmed the formation of self-assembled PAMAM/GO-WO3 nanostructures. Cyclic voltammetry (CV) and galvanostatic charge-discharge measurements revealed the electrocapacitive characteristics of the PAMAM/GO LbL films, with capacitance values of 7.08 mF/cm² and 27.70 F/g, and values of 6.8 mF/cm² and 73.58 F/g for the PAMAM/GO-WO3 LbL films, respectively, at a current of 1.1x10-5 A and a scan rate of 100 mV/s. All films showed high capacitive retention performance, with no capacitance loss over 2000 charge-discharge cycles. These results demonstrate that the investigated films have suitable properties to be explored in nanostructured systems for energy storage.