45 / 2026-09-17 18:44:21

Aluminum Silicate Nanosheets Couple Fast Electrochromism with Transparent Reflective cooling for Smart Windows

electrochromic smart window,PANI,Thermal management systems

Electrochromic windows provide dynamic solar regulation but often suffer from sluggish charge transport, cycling degradation, and secondary heat gain in the colored state. Here, negatively charged layered aluminosilicate (LAS) nanosheets were introduced into polyaniline (PANI) to regulate polymer-chain organization and interfacial charge transport. Structural characterization and charge-density calculations indicated possible hydrogen-bonding interactions, pronounced interfacial charge redistribution, and electron transfer from PANI to LAS. At an optimized LAS content of 10 wt%, the composite exhibited reduced charge-transfer resistance and improved electrochemical accessibility of PANI redox sites. A complementary PANI–LAS/ethyl-viologen electrochromic device delivered visible-to-near-infrared modulation, coloration and bleaching times of 4.9 and 3.7 s at 680 nm, and 90.1% optical-contrast retention after 8000 s of continuous switching. To mitigate solar-induced heating, a removable transparent LAS–PDMS overlay was integrated on the exterior side. Increasing the LAS loading enhanced solar reflectance while maintaining visible transmittance above 81% and nearly constant 8–13 µm emissivity. The overlay reduced the temperature rise after 60 s from 4.9 to 2.1 °C. These results establish interfacial regulation and transparent solar reflection as complementary strategies for fast, durable, and thermally adaptive electrochromic windows.