Copper(I)-Thiolate Coordination Polymers for In Situ Temperature Sensing in PDMS

Copper-thiolate coordination polymers (CPs) are photoluminescent compounds displaying good thermal stability and photoemission up to 120 °C, offering a high potential for optical temperature sensor applications. However, achieving composite films with stable RGB (red, green, and blue) emission remains a significant challenge in terms of material fabrication and photophysical efficiency. This study presents a process to disperse homogeneously insoluble red- and green-emissive CPs in PDMS (polydimethylsiloxane) matrices to fabricate environmentally friendly, transparent, flexible, stretchable, and large-scale composite films. Depending on the ratio of the mixture of three primary colors, red- and green-emissive CPs mixed with a blue-emissive organic polymer, a broad array of colored emissive composite films, including white, can be produced. Moreover, a composite film made of red- and green-emissive CPs has been studied for ratiometric temperature sensing. The temperature of the film can be directly read with a unique dual-camera setup, providing good spatial and temporal resolutions and thereby paving the way for optical temperature sensors complementary to traditional infrared cameras that enable the measurement of the temperature of surfaces.