Color‐Tunable Ultralong Organic Phosphorescence: Commercially Available Triphenylmethylamine for UV‐Light Response and Anticounterfeiting

Abstract Due to the unclear mechanism and lack of effective design for color‐tunable ultralong organic phosphorescence (UOP) in a single‐component molecule, the development of new types of single‐component UOP materials with color‐tunable property remains challenging. Herein, commercially available triphenylmethylamine‐based single‐component phosphors featuring color‐tunablity and ultralong lifetime (0.56 s) are reported. The changed afterglow colors from cyan to orange were observed after different wavelengths of UV excitation. Crystal structure and calculation studies show that multiple emission centers in the aggregated states may be responsible for the color‐tunablity. In addition, visual probing of UV light (from 260 to 370 nm) and colorful anti‐counterfeiting were conducted. More importantly, UV light ranging from 350 to 370 nm could be detected with the minimal interval of 2 nm. The findings provide a new type of single‐component color‐tunable UOP materials and shed new light on mechanism and design for such materials.