Open Access Nano Express

An effective oxidation approach for luminescence enhancement in CdS quantum dots by H2O2

Woojin Lee, Hoechang Kim, Dae-Ryong Jung, Jongmin Kim, Changwoo Nahm, Junhee Lee, Suji Kang, Byungho Lee and Byungwoo Park*

Author Affiliations

WCU Hybrid Materials Program, Department of Materials Science and Engineering, Research Institute of Advanced Materials, Seoul National University, Seoul, 151-744, Korea

For all author emails, please log on.

Nanoscale Research Letters 2012, 7:672  doi:10.1186/1556-276X-7-672

Published: 12 December 2012

Abstract

The effects of surface passivation on the photoluminescence (PL) properties of CdS nanoparticles oxidized by straightforward H2O2 injection were examined. Compared to pristine cadmium sulfide nanocrystals (quantum efficiency ≅ 0.1%), the surface-passivated CdS nanoparticles showed significantly enhanced luminescence properties (quantum efficiency ≅ 20%). The surface passivation by H2O2 injection was characterized using X-ray photoelectron spectroscopy, X-ray diffraction, and time-resolved PL. The photoluminescence enhancement is due to the two-order increase in the radiative recombination rate by the sulfate passivation layer.

Keywords:
Photoluminescence; Surface passivation; Quantum efficiency