Electrochemical Properties and Excited-State Dynamics of Azaperylene Derivatives

Akitsu Hirono, Hayato Sakai, Shuntaro Kochi, Tohru Sato, Taku Hasobe

Research output: Contribution to journalArticlepeer-review

2 Citations (Scopus)

Abstract

A series of azaperylene derivatives such as monoazaperylene (MAPery), 1,6-diazaperylene (1,6-DiAPery), 1,7-diazaperylene (1,7-DiAPery), 1,12-diazaperylene (1,12-DiAPery), triazaperylene (TriAPery), and tetraazaperylene (TetAPery) was synthesized by changing the position and number of nitrogen atoms at the bay region of a perylene skeleton in 1, 6, 7, and 12 positions. The density functional theory (DFT) calculations and electrochemical measurements suggested that the energies of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) states significantly become stabilized with increasing the number of nitrogen atoms, whereas the estimated HOMO-LUMO gaps approximately remain constant. This result is in good agreement with the absorption and fluorescence spectral measurements. Additionally, these steady-state spectroscopic measurements demonstrate the broadened spectra as compared to pristine perylene (Pery). In photophysical measurements, the fluorescence quantum yields (φFL) significantly decreased as the number of nitrogen atoms increased, whereas much enhanced quantum yields and rate constants of internal conversion (φIC and kIC) were observed. Especially, the increased kIC values of TriAPery (kIC: ∼108 s-1) and TetAPery (kIC: ∼109 s-1) are much larger than those of diazaperylene and monoazaperylene derivatives (kIC: ∼107 s-1). These photophysical trends were successfully explained by time-dependent DFT (TD-DFT) calculations. Finally, the characteristic protonated and deprotonated processes of nitrogen atoms in azaperylenes under acidic conditions were monitored utilizing absorption and fluorescence measurements. The binding constants demonstrate that the nitrogen atoms at 1 and 12 positions of a perylene skeleton are essential for the increased values.

Original languageEnglish
Pages (from-to)9921-9930
Number of pages10
JournalJournal of Physical Chemistry B
Volume124
Issue number44
DOIs
Publication statusPublished - 2020 Nov 5

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Surfaces, Coatings and Films
  • Materials Chemistry

Fingerprint

Dive into the research topics of 'Electrochemical Properties and Excited-State Dynamics of Azaperylene Derivatives'. Together they form a unique fingerprint.

Cite this