Robustification of ITO nanolayer by surface‐functionalization of transparent biopolyimide substrates

ABSTRACT Robust and transparent electrodes with good flexibility and high mechanical strength are required for preparing next‐generation electronic devices. Indium tin oxide (ITO) nanolayers have been grown by radio‐frequency sputtering process on reactive surface of transparent and thermostable biopolyimide, derived from an exotic aromatic amino acid, 4‐aminocinnamic acid (4ACA). It is observed that greater surface hydrophilicity of the biopolyimide induces stronger interfacial interaction with ITO nanolayer resulting in smoother surface of the bionanohybrids. Spectroscopy, microscopy, and X‐ray diffraction reveal the successful deposition of the ultra‐thin ITO nanolayer onto the surface‐engineered biopolyimide. The process provides transparent bionanohybrid films with robustness against mechanical deformation. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46709.