Facile Processing of Free-Standing Polyaniline/SWCNT Film as an Integrated Electrode for Flexible Supercapacitor Application

Abstract

Flexible supercapacitors (SCs) with compact configuration are ideal energy storage devices for portable electronics, owing to their original advantages (e.g., fast charging/discharging). To effectively reduce the volume of SCs, an integrated electrode of free-standing polyaniline (PANI)/single-wall carbon nanotube (SWCNT) film with high performance has been developed via a facile solution deposition method, which can be employed as current collector and active material in the meantime. Thanks to the strong π-π interactions between PANI and CNTs, an efficient conductive network with ordered PANI molecular chains is formed in this hybrid film electrode, which is beneficial for the ion diffusion process and fast redox reaction resulting in a high capacitance of 446 F g and outstanding cycling stability, achieving 98% retention over 13 000 cycles. Predictably, solid-state SCs constructed by this free-standing PANI/SWCNT film electrode exhibited remarkable mechanical stability and flexibility in a compact configuration, let alone its excellent capacitive performance (218 F g). Moreover, the highest energy density of flexible solid-state SC reached 19.45 Wh kg at a power density of 320.5 W kg, further indicating a good potential as an energy storage device. This work would inspire other simple process techniques for high-performance flexible SCs, catering to the demand of portable electronic devices.

Application of Polyaniline for Li‐Ion Batteries, Lithium–Sulfur Batteries, and Supercapacitors

“…The strong π–π interactions between CNTs and PANI provide abundant hydrophilic −NH− functionalities for hydrophobic CNTs. Thus, linear SCPs containing PANI and CNTs exhibit increased wettability, resulting in fast ion diffusion during charge/discharge and outstanding electrochemical performance . For example, Zhang et al .…”

“…Flexible SCPs composed of CNT@PANI have another form of planar (or film), except for yarns. For example, Liu et al . added SWCNTs into PANI–CSA solution and deposited a mixture of SWCNTs and PANI–CSA solution on a glass substrate.…”

“…Thus, linear SCPs containing PANI and CNTse xhibit increased wettability,r esulting in fast ion diffusion during charge/discharge and outstanding electrochemical performance. [104] For example, Zhang et al [105] wound two aligned CNT/PANI composite sheetsa rounde lastic polymer fibers as electrodes for as uperelastic SCP.T he composites exhibited a high specific capacitance (79.4 Fg À1 )a fter stretching at strain of 300 %f or 5000 cycles. Surprisingly,e ven at as tretching speed as high as 30 mm s À1 the specific capacitance was still maintained at 95.8 %o ft he initial capacitance at no strain.…”

One‐Pot Hydrothermal Synthesis of Ternary 1T‐MoS2/Hexa‐WO3/Graphene Composites for High‐Performance Supercapacitors

“…In recent years, supercapacitors have drawn wide attention as one of the most promising energy storage systems owing to the high power density and excellent life cycle properties . However, the main hindrance in their application is the low energy density.…”

“…In recenty ears, supercapacitors have drawn wide attention as one of the mostp romising energy storage systemso wing to the high powerd ensity and excellent life cyclep roperties. [1,2] However,t he main hindrance in their application is the low energy density.T he performance of the supercapacitors mainly relies on the electrode materialsh aving properties of high electricalc onductivity,e asy charge( ion/electron) transportation, adequatep orosity,a nd highs urfacea rea. [3,4] Supercapacitors can store chargeb yi on adsorption (electrochemical double layer capacitors,E DLCs)a nd redox faradaic reaction (pseudocapacitors).…”