Electronic Modulation Induced Luminescence from Triphenylamine Derivative and Temperature Sensor Application

Abstract In recent years, numerous long‐lived organic room temperature phosphorescence (RTP) systems have been well explored. However, the RTP emission mechanism of organic compounds is still not very clear. The structures of terphenyl amines (TPAs) are simple and their chromophores are definite, which makes them suitable for exploring the emission mechanism of organic RTP materials. A series of TPA derivatives are synthesized in this contribution. Excitingly, benefiting from a facile electronic characteristic modulation strategy, RTP emissions generated from TPAs are achieved successfully. The theoretical calculation and crystallographic analysis reveal that introducing electron‐donating substitutes is beneficial for the formation of a clear charge separation state and promoting triplet state energy transfer. This is the primary reason for the promotion effects of the electron‐donating substitutes on RTP emission. By varying the substituents and their substitution sites, the afterglow colors as well as the lifetime and efficiency of the resultant TPAs can be facilely tuned. Interestingly, o‐TPA‐OMe shows a temperature‐dependent fluorescence emission. Benefiting from these inspiring photoluminescence performances, these TPA derivatives can be applied in information encryption and temperature sensors.