title: Tuning luminescent properties of CdSe nanoclusters by phosphine surface passivation.
abstract: Appropriate surface ligands are required for tuning the physicochemical and photophysical properties of nanoclusters (NCs). These surface ligands are especially critical for passivating the small (CdSe)33,34NCs where the majority of atoms are at the NC surface. In this study, triphenylphosphine (TPP), trioctylphosphine (TOP) and tris(pentafluorophenyl)phosphine (TPFP) have been tested as capping agents for alkylamine-coated CdSe NCs. TPP and TOP compounds are found to increase the quantum yield of photoluminescence (PL) from 0.15% to 0.6% and 0.53%, respectively, and to preserve this increased PL with time, probably by preventing charge leakage as a result of their binding to Se atoms. Since no dramatic change in the shape of NCs' PL spectrum occurs after surface treatment, both the exciton band and the low-energy broad band in magic NCs are thought to describe the intrinsic luminescence properties of the NCs. As a result, the PL increase due to Se passivation is thought to be mainly caused by a decrease in the efficiency of the NC nonradiative pathways.
authors.affiliation: Taras Shevchenko National University of Kyiv, 64/13, Volodymyrska Str., Kyiv 01601, Ukraine. Laboratoire de Biophotonique et Pharmacologie, UMR 7213 CNRS, Université de Strasbourg, Faculté de pharmacie, 74 route du Rhin, 67401 ILLKIRCH Cedex, France. These authors equally contributed to the work.
authors.forename: Iryna
authors.initials: I
authors.lastname: Lysova
authors.forename: Halina
authors.initials: H
authors.lastname: Anton
authors.forename: Igor
authors.initials: I
authors.lastname: Dmitruk
authors.forename: Yves
authors.initials: Y
authors.lastname: Mely