Origin of the Enhanced Photoluminescence from Semiconductor CdSeS Nanocrystals

Sarma, DD and Nag, Angshuman and Santra, Pralay K and Kumar, Akshay and Sapra, Sameer and Mahadevan, Priya (2010) Origin of the Enhanced Photoluminescence from Semiconductor CdSeS Nanocrystals. In: Journal of Physical Chemistry letters, 1 (14). pp. 2149-2153.

PDF physicals.pdf - Published Version Restricted to Registered users only Download (2MB) | Request a copy

Abstract

Internal structures of extraordinarily luminescent semiconductor nanoparticles are probed with photoelectron spectroscopy, establishing a gradient alloy structure as an essential ingredient for the observed phenomenon. Comparative photoluminescence lifetime measurements provide direct evidence for a minimization of nonradiative decay channels because of the removal of interfacial defects due to a progressive change in the lattice parameters in such graded structures, exhibiting a nearly single exponential decay Quantum mechanical, calculations suggest a differential extent of spatial collapse of the electron and the hole wave functions in a way that helps to enhance the photoluminescence efficiency, while at the same time increasing the lifetime of the excited state, as observed in the experiments.

Item Type:	Journal Article
Publication:	Journal of Physical Chemistry letters
Publisher:	American Chemical Society
Additional Information:	Copyright of this article belongs to American Chemical Society.
Keywords:	CdSe/CdSeS/CdS core/gradient-shell/shell;luminescence; heterostructured nanocrystals;tight binding calculations; fluorescence lifetime.
Department/Centre:	Division of Chemical Sciences > Solid State & Structural Chemistry Unit
Date Deposited:	11 Aug 2010 06:23
Last Modified:	19 Sep 2010 06:13
URI:	http://eprints.iisc.ac.in/id/eprint/31214

Actions (login required)

View Item