Superhydrophobic Thermochromic Coating With Dual Photo‐Electrothermal Modulation for All‐Season Energy Efficiency Smart Window

ABSTRACT Vanadium dioxide (VO 2 )‐based thermochromic smart windows enable autonomous regulation of sunlight for building energy savings; however, challenges remain in achieving high visible transmittance, low transition temperature, and reliable controllability. Herein, this study presents a sandwich‐structured multifunctional coating that integrates superhydrophobicity, thermochromism, and photothermal–electrothermal responsiveness. The system comprises a transparent polydimethylsiloxane (PDMS)/MXene–silver nanoparticles (AgNP) photothermal layer, a conductive silver nanowires (AgNWs) electrothermal interlayer, and a VO 2 ‐embedded polyvinylidene fluoride‐trifluoroethylene (PVDF‐TrFE)/PDMS nanofiber thermochromic layer with superhydrophobicity for solar thermal switching. This design enables rapid and energy‐efficient VO 2 phase transitions, achieving luminous transmittance of 73.9% and solar modulation of 12.48%. Furthermore, the coating adaptively regulates thermal emissivity, enhancing radiative cooling under hot conditions and minimizing heat loss in cold climates, resulting in a 36.73% reduction in annual heating, ventilation, and air conditioning (HVAC) energy consumption and mitigation of carbon emissions to 62.8 kg m −2 . Its micro/nanostructured surface exhibits excellent superhydrophobicity (152° water contact angle, 5.1° ± 0.7 sliding angle), providing self‐cleaning capability and strong anti‐icing performance by delaying ice formation 12.3‐fold and reducing ice adhesion to 31.4 N compared with bare glass. This integrated design overcomes optical–thermal–durability trade‐offs and demonstrates strong potential for energy‐efficient smart window applications in sustainable buildings.