Constructing a Self-Referenced NIR-II Thermometer with Energy Tuning of Coordinating Water Molecules by a Minimalist Method

Fluorescence thermometry based on metal halide perovskites is increasingly becoming a hotspot due to its advantages of high detection sensitivity, noninvasiveness, and fast response time. However, it still presents certain technical challenges in practical applications, such as complex synthesis methods, the use of toxic solvents, and being currently mainly based on the visible/first near-infrared light with poor penetration and severe autofluorescence. In this study, we synthesize the second near-infrared (NIR-II) luminescent crystals based on Yb