Synergistic Effect of ZnO and Acid‐Functionalised Carbon Nanotubes on Improving the Specific Capacitance of Poly(ortho‐Phenylenediamine‐co‐Aniline)‐Based Wearable Electronics

The fabrication of highly conducting composites which can be seamlessly integrated into fabric substrates is exceedingly imperative for the development of versatile wearable electronics with long cycling stability and high specific capacitance. Previously, our group has reported the synthesis of poly(ortho‐phenylenediamine‐co‐aniline) using microwave irradiation and we have evaluated the electrochemical properties of both the copolymer and its nanocomposite with acid functionalized carbon nanotubes as wearable electronics. Herein, we design a nanocomposite of zinc oxide decorated acid functionalized carbon nanotubes and the aforementioned copolymer with the aim to evaluate the simultaneous effects of pseudocapacitance and electrical double layer capacitance in the copolymer matrix. The samples were comprehensively characterized using various techniques. These materials were coated on fabric substrates to evaluate their applicability as wearable electronics. A high specific capacitance of 225.95 F g−1 at 0.50 A g−1 was obtained and 88 % of the initial capacitance was retained after 1000 cycles. The in vitro cytotoxicity studies for the nanocomposite showed lower cytotoxicity between the concentration ranges of 50–200 μg/mL. Combination of biocompatibility and enhanced electrochemical performance establishes the unprecedented application of these devices in the field of biocompatible wearable electronics. Wearable electronic devices were developed using CNT‐COOH/ZnO functionalized poly(ortho‐phenylenediamine‐co‐aniline). Enhanced electrochemical performances were obtained owing to the synergistic effects arising from pseudocapacitance and electric double layer capacitances. The successful embedment of the nanomaterials in the copolymer matrix also resulted in high biocompatibility.