Unconventional Fluorescence Quenching in Naphthalimide-Capped CdSe/ZnS Nanoparticles

Aguilera-Sigalat, J; Pais, VF; Domenech-Carbo, A; Pischel, Uwe; Galian, RE; Perez-Prieto, J

HERO ID

3575396

Reference Type

Journal Article

Year

2013

HERO ID 3575396
In Press No
Year 2013
Title Unconventional Fluorescence Quenching in Naphthalimide-Capped CdSe/ZnS Nanoparticles
Authors Aguilera-Sigalat, J; Pais, VF; Domenech-Carbo, A; Pischel, Uwe; Galian, RE; Perez-Prieto, J
Journal Journal of Physical Chemistry C
Volume 117
Issue 14
Page Numbers 7365-7375
Abstract Core-shell (CS) CdSe/ZnS quantum dots (QD) capped with ligands that possess a mercapto or an amino group and a naphthalimide (NI) as chromophore unit, linked by a short ethylene chain (CS@S-NI and CS@H2N-NI, respectively), have been synthesized and fully characterized by infrared and nuclear magnetic resonance spectroscopies, high-resolution transmission electron microscopy, and voltammetry as well as by steady-state absorption and emission spectroscopies. The organic ligands HS-NI and H2N-NI act as bidentate ligands, thereby causing a drastic decrease in the QD emission. This was particularly evident in the case of CS@S-NI. This behavior has been compared with that of commercially available QDs with octadecylamine as the surface ligand and a QD capped with decanethiol ligands (CS@S-D). The interaction between the anchor groups and the QD surface brings about different consequences for the radiative and nonradiative kinetics, depending on the nature of the anchor group. Our results suggest that the naphthalimide group "stabilizes" empty deep trap states due to the carbonyl group capacity to act as both a sigma-donor and a pi-acceptor toward cations. In addition, the thiolate group can induce the location of electron density at shallow trap states close to the conduction band edge due to the alteration of the QD surface provoked by the thiolate binding.
Doi 10.1021/jp3128252
Wosid WOS:000317552200051
Is Certified Translation No
Dupe Override No
Is Public Yes