Transparent polyaniline/MXene thin films supercapacitors

Abstract

We report the successful synthesis of nanocomposites between the MXene Ti₃C₂T_x and polyaniline (PAni), achieved via an innovative approach starting from the intercalation of anilinium ions into non-exfoliated Ti₃C₂T_x, and followed by a liquid/liquid interfacial polymerization. This approach produces transparent films with beneficial optical quality. The spectroscopic analysis confirmed the formation of PAni in its conductive form, emeraldine salt. The absence of TiO₂ bands in the Raman spectra indicated that the organic polymer protected Ti₃C₂T_x from degradation, even in acidic media. Electrochemical characterization revealed that the nanocomposites exhibited promising performance as supercapacitors, with specific capacity dependent on the amount of polymer. The combination of the conductive Ti₃C₂T_x and the redox activity of PAni, as well as the specific nanoarchitecture in which the materials are organized, significantly improved the electrochemical response, facilitating ion diffusion. These transparent films demonstrated specific capacity values up to 89 mAh g^-1 at 0.1 mAh g^-1, with the potential for further enhancement through current collector optimization, positioning them as strong candidates for miniaturized energy storage applications and transparent devices.