Reversible visible/near-infrared light responsive thin films based on indium tin oxide nanocrystals and polymer

In this study, we design a novel thermo- and photo-responsive nanocomposite film prepared by depositing indium tin oxide nanocrystals via the coating of amphiphilic copolymer on polycaprolactone substrates (INCP). The INCP film shows reversible surface morphology change properties by changing temperature as well as turning ON/OFF NIR laser. Especially, as the temperature changes from 25 to 75 °C, the film could regulate light transmittance from 75 to 90% across the visible and near-infrared region (500-1,750 nm). In addition, the film also exhibits excellent recycle and thermal stability at different temperature. Our results reveal that reversible surface morphology change properties are caused by curvature adjustment of film, which is owing to the coupling effect between copolymer and PCL with different thermal expansion strains. Our results suggest a possible strategy for the preparation of smart responsive materials in the future, which provides a reference for the development of new energy-saving materials.