Upscalable ultra thick rayon carbon felt based hybrid organic‐inorganic electrodes for high energy density supercapacitors

Abstract

Low weight, small footprint, and high performances are essential requisites for the implementation of energy storage devices within consumer electronics. One way to achieve these goals is to increase the thickness of the active material layer. In this work, carbonized and graphitized rayon felt, a cellulose-derived material, is used as a three-dimensional current collector scaffold to enable the incorporation of large amount of active energy storage materials and ionic liquid-based gel electrolyte in the supercapacitor devices. PEDOT:PSS, alone or in combination with active carbon, has been used as the active material. Three-dimensional supercapacitors with high per unit area capacitance (more than 1.1 F/cm 2 ) have been achieved owing to the loading of large amount of active material in the felt matrix. Areal energy density of more than 101 μWh/cm 2 and areal power density of more than 5.9 mW/cm 2 have been achieved for 0.8 V operating voltage at a current density of 1 mA/cm 2 . A nanographite material was found to be beneficial in reducing the internal serial resistance of the supercapacitor to lower than 1.7 Ω. Furthermore, it was shown that even after 2000 times cycling test, the devices could still retain its performance with at least 88% coulombic efficiency for all the devices.All the materials are readily available commercially, environmentally sustainable and the process can potentially be upscaled with industrial process.

Pedot:PSS/Graphene Oxide (GO) Ternary Nanocomposites for Electrochemical Applications

“…The capacitive properties of the PEDOT: PSS-based inks, obtained by adding GO blended with G or AA, were studied by CV tests in PBS solution. The CV plots of PEDOT:PSS show a broad, approximately rectangular shape ( Figure 6 a), which can be attributed to a large double-layer capacitance [ 47 , 48 ]. The enclosed area of the CV curves, which corresponds to the electrode charge storage capacity, strongly depends on the ink properties [ 47 ].…”

“…The CV plots of PEDOT:PSS show a broad, approximately rectangular shape ( Figure 6 a), which can be attributed to a large double-layer capacitance [ 47 , 48 ]. The enclosed area of the CV curves, which corresponds to the electrode charge storage capacity, strongly depends on the ink properties [ 47 ]. The addition of GO, with or without the two green additives, apparently causes no visible difference in the obtained curves.…”