Optical, electrochemical, photoelectrochemical and electrochromic properties of polyamide/graphene oxide with various feed ratios of polyamide to graphite oxide

A series of novel multicoloured near-infrared electrochromic polyamide (PA)-based nanocomposites with graphene were successfully prepared via in situ chemical polymerization with various feed ratios of PA to graphene oxide (GO) (PA : GO = 999 : 1, 199 : 1, 49 : 1, 19 : 1, 1 : 0). The prepared nanocomposites were readily soluble in many organic solvents and displayed outstanding thermal resistance, stability of electrochromic characteristics, high coloration efficiency, short switching time, and anodic electrochromic behavior, and showed a good and uniform dispersion of the GO sheets in the PA matrix. The typical, stable photoelectrical response showed that there was charge transfer in the interior of the composites film under illumination, and the enhanced electrochemical performance was also investigated by electrochemical impedance spectroscopy (EIS) technique. The content of GO played a pivotal role in the electron transfer and regulated the conductivity of the composites. The properties prove that the composite is a multipurpose material which will cater for photoelectric conversion and electrochromic application.