Crack-free fabrication of Prussian blue-based blending film for the dramatic enhancement of dual electrochromic device

Abstract

We introduce a method based on particle-printing technology to facilitate the fabrication of crack-free dual electrochromic devices (ECDs). A film prepared by blending Prussian blue (PB) with antimony tin oxide (ATO) powders had a dense structure free of surface cracks and was suitable as both anode and ion storage layers. We investigated the deposition conditions as a function of substrate temperature at room temperature, 80 °C, and 150 °C. The PB/ATO blending film formed at 150 °C had a uniform surface and high crystallinity; this was the optimal substrate temperature. At 150 °C, the as-fabricated dual ECD had an improved diffusion coefficient of 8.70 × 10−9 cm2/S due to the presence of the PB/ATO blending film. Moreover, there was over 4-fold improvement in the transmittance change at 800 nm compared with that of the WO3 film only with no anodic layer. The better ECD properties were attributed to improved ion mobility and ion storage capacity. Therefore, this blending film was successfully fabricated on the substrate without any cracks using facile particle printing technology to be served as both anodic and ion storage layer.