All‐Dielectric‐Based Highly Transparent Self‐Cleaning Coating for Efficient Solar Heat and UV Blocking in Single‐Pane Glass Windows

ABSTRACT Blocking solar infrared (IR) radiation is essential to reduce indoor temperatures, thereby lowering the load and electrical energy consumption of heating, ventilation, and air conditioning (HVAC) systems. However, achieving a cost‐effective, large‐area‐compatible design that offers high visible transmission while blocking IR and ultraviolet (UV) regions remains a significant challenge. Here, we present a novel, self‐cleaning, tint‐free window design employing an all‐dielectric nanoscale multilayer structure to block UV and IR radiation while maintaining high visibility. The fabricated device exhibits visible transmittance of 77.8%, UV blocking of 96.2%, and IR blocking of 76.3%, thereby achieving both energy efficiency and aesthetic appeal. The design achieves maximum temperature reductions of 14.5°C and 11°C in solar simulator and outdoor daytime experiments, respectively, compared to a bare glass window, demonstrating effective regulation of thermal gain, further corroborated by OpenStudio simulations. Additionally, the design exhibits polarization‐independent behavior and maintains angular stability up to 45° incidence angle, validated through simulation and experimental analyses. This advanced multilayer coating is superhydrophilic, enabling self‐cleaning behavior at very low sliding angles. The window design integrates superior triband optical properties, self‐cleaning capabilities, and dramatically reduces indoor thermal loads and energy consumption, offering a sustainable solution by lowering operational costs and associated carbon emissions.