Photo/Thermal Dual‐Responsive Nanocomposite Organohydrogel Smart Window With Intrinsic UV Shielding for Selective Light Management and Synergistic Cooling

Spectrally selective transmission of solar radiation is vital to balance energy efficiency, visual comfort, and UV protection in the human environment. Thermochromic materials regulate solar spectral transmission through temperature‐dependent optical transitions, but their single thermal responsiveness limits precise spectral control, leading to inefficient utilization of light and insufficient UV protection. To overcome these limitations, we implement a dual‐responsive strategy that synergizes photochromic and thermochromic mechanisms by developing a nanocomposite organohydrogel integrating photochromic perovskite nanosheets and a thermochromic poly( N ‐isopropylacrylamide‐co‐acrylamide) network in a water‐glycerol matrix, forming a photo/thermal dual‐responsive smart window (PTSW). Acrylamide and glycerol synergistically enhance dimensional stability and environmental tolerance, ensuring reliable performance under diverse climatic conditions. The perovskite nanosheets efficiently absorb and scatter UV light, blocking UV transmittance greatly while maintaining high visible transparency. The PTSW with a 1 mm‐thick gel layer exhibits pronounced solar modulation, reducing indoor temperature by up to 17.3°C relative to double glazing in outdoor experiments, and achieves ∼20% simulated annual energy savings in high‐irradiance regions. Climatic wind‐tunnel experiments further confirm the PTSW's excellent weather adaptability and cycling durability. This dual‐responsive smart window establishes a general pathway for intelligent selective solar‐spectrum management, UV protection, and sustainable thermal regulation toward carbon‐neutral building technologies.