Flexible Supercapacitors With Improved Energy Density Using OPBI-Coated Polyaniline- Carbon Nanotube Blends

Conductive organic materials have gained burgeoning attention as well as widespread popularity as transition metal oxide-free and cost-effective electrode materials for supercapacitors (SCs). However, the main challenges associated with organic electrodes are lower energy storage performance and poor electrochemical stability in aqueous electrolytes. Herein, we designed a novel organic composite electrode composed of poly (4,
$4^{\prime }$
-diphenyl ether-5,
$5^{\prime }$
-bis benzimidazole) layered polyaniline-carbon nanotubes (OPBI-PANI@CNTs) for high-energy density flexible SCs. The prepared OPBI-PANI@CNTs composite resulted in a uniformly blended and 3-D network with good conductivity, leading to higher electrochemical properties and long-cycling life. Altering the content of OPBI loading on PANI@CNTs, the energy storage properties were also investigated. Specifically, the symmetric SCs assembled with 5% OPBI-PANI@CNTs composite showed the higher specific capacitance of 572 F/g at 1.3 A/g with good cyclic stability. The SCs also showed high energy and power density of (19.8 Wh/kg and 0.648 kW/kg), which are higher/comparable to the state-of-art organic materials-based SCs. The proposed organic composite with high conductivity and superior energy storage could be expected to utilize as advanced electrode material for electrochemical devices.