High-performance supercapacitor electrode synthesized by in-situ chemical oxidative polymerization of TiO2/PANI composite

Abstract

Supercapacitors have emerged as potent energy storage devices for the past few decades. Researchers are putting their best efforts into fabricating a device that offers high capacitance as well as high energy and power density by merging different classes of materials. In this pursuit, polyaniline (PANI) is considered a potential material for supercapacitor electrodes because it offers good conductivity, ease of processing, and the possibility of making composite with other materials. The drawback of PANI is the lack of stability that decreases because of the volumetric changes occurring during redox reactions. On the other hand, TiO₂ is considered a good supercapacitor electrode material because it offers high chemical stability, non-toxicity, and low cost. However, the specific capacitance achieved from it is low due to its low conductivity. Herein, we report the TiO₂/PANI composite by in-situ chemical oxidative polymerization method to enhance the performance of supercapacitor electrodes through a synergistic effect. An optimal addition of 5 wt.% TiO₂ in PANI resulted in high specific capacity of 925 C/g at 1 A/g current density.