Exciton Migration and Surface Trapping for a Photonic Crystal Displaying Charge-Recombination Fluorescence

Yükleniyor...
Küçük Resim

Tarih

2016

Dergi Başlığı

Dergi ISSN

Cilt Başlığı

Yayıncı

Wiley-V C H Verlag Gmbh

Erişim Hakkı

info:eu-repo/semantics/closedAccess

Özet

A compact donor-acceptor molecular dyad has been synthesized by attaching an N,N-dimethylamino fragment to a naphthalic anhydride residue. The dyad shows fluorescence from an intramolecular charge-transfer state (i.e., charge-recombination fluorescence) in solution, with the photo-physical properties being strongly dependent on the solvent polarity. Similar emission is seen for single crystals of the target compound, the molecules being aligned head-to-head, although time-resolved emission profiles display dual-exponential kinetics. A second polymorph with the head-to-tail alignment also gives rise to two lifetimes that differ somewhat from those of the first structure, which are assigned to bulk and surface-bound molecules. Growing the crystal in the presence of Rhodamine B localizes the dye around the surface. Excitation of the crystal is followed by sub-ps exciton migration along the aligned stacks, with occasional crossing to adjacent stacks and trapping at the surface. Rhodamine B present at very low levels acts as the acceptor for excitons entering the surface layer. Crystals embedded in a polyester resin form an artificial light-harvesting antenna able to sensitize an amorphous silicon solar cell.

Açıklama

Waddell, Paul/0000-0002-7851-7347; AL-AQAR, ROZA ABDULRAZAQ SALIH/0000-0001-9960-1313; Harriman, Anthony/0000-0003-0679-2232; Benniston, Andrew/0000-0001-8878-5014
WOS: 000384807600008
PubMed: 27597381

Anahtar Kelimeler

electronic energy transfer, fluorescence, light harvesting, photophysics, polymorph

Kaynak

Chemistry-A European Journal

WoS Q DeÄŸeri

Q1

Scopus Q DeÄŸeri

Q1

Cilt

22

Sayı

43

Künye