Optical and Thermal Switching of Liquid Crystals for Self‐Shading Windows

A liquid crystal light shutter whose transmittance can be controlled by ambient conditions, such as incident solar UV intensity and outdoor temperature, is demonstrated. Self‐shading by optical or thermal switching between transparent and opaque states is achieved by liquid crystals doped with push–pull azobenzene and can be used for energy‐saving smart windows. The self‐shading light shutter is transparent during cool weather or under weak sunlight, which could save the energy used for heating and lighting, and can be switched from transparent to opaque during warm weather or under strong sunlight, saving energy used for cooling. An optically and thermally switchable liquid crystal cell has the ability to control the transmission of light and heat, allowing its application in smart windows that can dramatically reduce energy consumption. The transmittance of self‐switching smart windows can be adjusted by ambient conditions, such as the incident solar UV intensity and outdoor temperature.