Unusual photoluminescence characteristics of tetraphenylpyrene (TPPy) in various aggregated morphologies
2006; Elsevier BV; Volume: 421; Issue: 1-3 Linguagem: Inglês
10.1016/j.cplett.2005.12.102
ISSN1873-4448
AutoresTakahito Oyamada, Seiji Akiyama, Masayuki Yahiro, Mari Saigou, Motoo Shiro, Hiroyuki Sasabe, Chihaya Adachi,
Tópico(s)Organic Electronics and Photovoltaics
ResumoWe found that 1,3,6,8-tetraphenylpyrene (TPPy) demonstrates unusual photoluminescence (PL) characteristics in the solid-state morphologies. We investigated the PL characteristics of TPPy in various morphologies including powder, deposited film, and solutions. The TPPy powder (A), which was prepared through column chromatography, recrystallization, and train sublimation, showed blue fluorescence with a peak of maximum wavelength of λmax = 451 nm. The TPPy powder (B), which was obtained by thermal annealing of TPPy powder (A) in a quartz tube in nitrogen, showed green fluorescence with λmax = 510 nm. Furthermore, the TPPy powder (B) was reversibly converted into TPPy powder (A) by recrystallization. We conclude that TPPy dimers form locally in the TPPy monomer aggregates during thermal annealing and redissociate into the monomer states during recrystallization.
Referência(s)