A “Hand‐In‐Hand” Thermal‐Responsive Cyclodextrin Material Designed for Liquid Smart Windows

Abstract Thermochromic smart windows have emerged as a focal point in energy research. In this study, a novel approach is introduced for developing thermoresponsive materials for smart windows, utilizing microscopic agglomeration of molecules to regulate incident light. The groundbreaking material, β‐CD‐Val‐IBAm 4 , is constructed by grafting four isobutylated valines onto natural β‐cyclodextrins. This material exhibits a unique “hand‐in‐hand” effect, resulting from the interaction of isobutylated valine side chains, which leads to molecular aggregation and reduced light transmission at elevated temperatures. The hydration–dehydration process is related to molecular aggregation rather than crosslinking, ensuring the structural integrity and uniformity of the smart windows. Molecular dynamics simulations and 2D NOESY confirm the thermal response mechanism of β‐CD‐Val‐IBAm 4 . When dissolve in a glycerol‐water binary solvent system, the material forms a thermochromic liquid with outstanding optical performance (Δ T sol of 1 mm liquid can reach 69.8%) and long‐term stability. This innovative approach opens new avenues for the advancement of next‐generation smart window technologies.