DNA hydrogel templated carbon nanotube and polyaniline assembly and its applications for electrochemical energy storage devices

Abstract

Functional nanocomposites comprising of biomaterials and non-biomaterials are one of the main subjects of recent research due to their wide range of potential applications. Here, we demonstrate that the porous DNA hydrogel (Dgel) can be an excellent template for combining carbon nanotubes (CNTs) and polyaniline (PANI) resulting in high performance supercapacitor electrodes. These hybrid supercapacitors have been constructed by electrostatic deposition of conductive CNTs on DNA hydrogel followed by coating of PANI pseudocapacitor. Performances of supercapacitors in terms of specific capacitance, cycling stability, power density, and energy density have been systematically investigated. The specific capacitance of these DNA hydrogel based supercapacitors has reached up to 146.4 F g⁻¹ with a power density of 23.3 kW kg⁻¹ and an energy density of 13.0 Wh kg⁻¹ in acidic media which is higher than commercially available products. In addition, the cytotoxicity of our supercapacitors was evaluated in vitro in cell culture media during the charge–discharge processes. In both human and mouse skin cell culture media, our devices exhibited zero cytotoxicity. Our novel biological hybrid electrodes can be a platform towards biocompatible and implantable energy storage devices for in vivo applications.