Continuous Solar Energy Conversion Windows Integrating Zinc Anode-Based Electrochromic Device and IoT System.

Integration of solar cells and electrochromic windows offers crucial contributions to green buildings. Solar-charging zinc anode-based electrochromic devices (ZECDs) present exciting opportunities for addressing the solar intermittency issue. However, the limited energy storage capacity of ZECDs results in wasted harnessing of solar energy as well as overcharging of ZECDs. Herein, we report spectral-selective dual-band ZECDs that continuously transport solar energy to indoor appliances by remotely controlling the repeated bleached-tinted (i.e., charged-discharged) cycles during the daytime. Hexagonal phase cesium-doped tungsten bronze (h-Cs 0.32 WO 3 , CWO) nanocrystals are adopted for dual-band ZECDs for the first time, due to their remarkable independent control ability of near-infrared (NIR) and visible (VIS) light transmittance (∆T = 73.0%, 700 nm; ∆T = 83.7%, 1200 nm), and excellent cycling stability (0.8% optical contrast decay at 1200 nm after 10000 cycles). The prototype device (i.e., CWO//Zn//CWO) delivers extraordinary thermal insulation capability, displaying a 10 °C difference between "bright" and "dark" modes. Furthermore, we developed an Internet of Things (IoT) controller to independently control the NIR and VIS lights of the CWO//Zn//CWO window wirelessly with a smartphone, empowering the continuous discharging of the solar-charged window during the daytime remotely. Such windows represent an intriguing potential technology whose future impact on green buildings may be substantial. This article is protected by copyright. All rights reserved.