NiO Nanocrystalline/Reduced Graphene Oxide Composite Film with Enhanced Electrochromic Properties

Abstract

The NiO nanocrystalline/reduced graphene oxide (rGO) composite film was successfully synthesized using a simple hot-injection and dip coating method. The as-prepared samples were characterized using X-ray diffraction (XRD), Raman, scanning electron microscope (SEM), ultraviolet and visible spectrophotometer (UV). Compared to the NiO film, the NiO nanocrystalline/rGO composite film exhibits enhanced electrochromic properties and large [Formula: see text] (40.7% at 550[Formula: see text]nm), fast switching speed ([Formula: see text].3[Formula: see text]s and [Formula: see text].9[Formula: see text]s), high coloration efficiency (12.85[Formula: see text]cm 2 C[Formula: see text] and better cycling performance (1000 cycles). The improvement of the electrochromic properties was attributed to the large specific surface area and good conductivity of the rGO.