Facile preparation of WO3/PEDOT:PSS composite for inkjet printed electrochromic window and its performance for heat shielding

•An electrochromic ink applied for inkjet printing has been prepared.•The hybrid type electrochromic device has been constructed.•The ECD can efficiently block the sunlight and reduce solar heat gain.

In this study, we have prepared an electrochromic (EC) ink composed of WO3 nanoparticles and poly (3,4-ethylenedioxythiophene):poly (styrene sulfonate) (PEDOT:PSS). The ink formulation can be processed through inkjet-printing or spray coating to deposit high-quality EC layers. The PEDOT:PSS acts as an conductive binder to connect the WO3 nanoparticles leading to reduced impedance and better electrochemical properties. The WO3/PEDOT:PSS (PH1000) exhibits an optical modulation of 54.1%, a response time of 1.1 s, and a coloration efficiency of 83.87 cm2/C. A hybrid type electrochromic device (ECD) incorporated with WO3/PEDOT:PSS with excellent durability has been fabricated. The performance of WO3/PEDOT:PSS based ECD for sun shielding property is also evaluated. The ECD can efficiently block the sunlight and reduce solar heat gain. As a result, the indoor temperature can be modulated from 32.7 °C (bleached state) to 29.4 °C (darken state) under illumination.