Affiliation:
1. Key Laboratory for Material Chemistry of Energy Conversion and Storage Ministry of Education School of Chemistry and Chemical Engineering State Key Laboratory of Materials Processing and Die & Mould Technology Huazhong University of Science and Technology Wuhan 430074 China
2. School of Chemistry Chemical Engineering and Life Science State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 China
Abstract
AbstractAccidentally, it was found that triphenylamine (TPA) from commercial sources shows ultralong yellow‐green room temperature phosphorescence (RTP) like commercial carbazole, which however disappears for lab‐synthesized TPA with high purity. Herein, we for the first time identify the impurity types that cause RTP of commercial TPA, which are two N, N‐diphenyl‐naphthylamine isomers. Due to similar molecular polarity and very trace amount (≈0.8 ‰, molar ratio), these naphthyl substituted impurities can be easily overlooked. We further show that even at an extremely low amount (1000000 : 1, mass ratio) of impurities, RTP emission is still generated, attributed to the triplet‐to‐triplet energy transfer mechanism. Notably, this doping strategy is also applicable to the triphenylphosphine and benzophenone host systems, of which strong RTP emission can be activated by simply doping the corresponding naphthyl substituted analogues into them. This work therefore provides a general and efficient host/guest strategy toward high performance and diverse organic RTP materials.
Funder
National Natural Science Foundation of China