Enhancing the Electrochromic Stability of Prussian Blue Based on TiO2 Nanorod Arrays
In this paper, we report a simple two-step hydrothermal method to improve the cyclic stability and transmittance of the Prussian blue (PB) with TiO2 nanorod arrays (TNRA). The TNRA were used as a nanostructure substrate and to investigate the electrochromic properties of the PB/TNRA hybrid film. The PB/TNRA film shows excellent cyclic stability (83.8% after 1000 cycles) compared with that of pure PB film (83.8% after 400 cycles). The improved cyclic stability was attributed to the increased adhesion between the PB film and substrate and the alleviated volume expansion during the ion intercalation/deintercalation process. Moreover, the TNRA can reduce the reflectivity of the PB/TNRA film and increase the loading of PB, therefore, the PB/TNRA film also shows larger optical modulation (85.8% at 700 nm) and high coloration efficiency (102.08 cm2·C-1).