Journal of Nanoparticle Research

, Volume 12, Issue 7, pp 2655–2666 | Cite as

Study of energy transfer from capping agents to intrinsic vacancies/defects in passivated ZnS nanoparticles

Research Paper

Abstract

The study of energy transfer mechanism from different capping agents to intrinsic luminescent vacancy centres of zinc sulphide (ZnS) has been reported in the present work. Nanoparticles of capped and uncapped ZnS are prepared by co-precipitation reaction. These nanoparticles are sterically stabilized using organic polymers—poly vinyl pyrrolidone, 2-mercaptoethanol and thioglycerol. Monodispersed nanoparticles were observed under TEM for both capped and uncapped ZnS nanopowders. However, for uncapped ZnS nanopowders, tendency for formation of nanorod like structure exists. Size of ZnS crystallites was calculated from X-ray diffraction pattern. The primary crystallite size estimated from X-ray diffraction pattern is 1.95–2.20 nm for capped nanostructures and 2.2 nm for uncapped nanostructures. FTIR spectra were conducted to confirm capping. Zeta potential measurements have been done to check the stability of dispersed nanoparticles. Band gap measurement was done by UV–visible spectrophotometer. Excitation and emission spectra are also performed in order to compare optical properties in various samples. Increase in emission intensity and band gap has been observed by adding different capping agents in comparison to uncapped ZnS nanoparticles. The results show that in capped ZnS nanoparticles the mechanism of energy transfer from capping layer to photoluminescent vacancy centres is more pronounced.

Keywords

Capping Uncapped Excitation Emission Semiconductor nanoparticles 

Notes

Acknowledgements

The authors are thankful to DRDO, New Delhi for financial assistance.

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Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  1. 1.School of Physics and Materials ScienceThapar UniversityPatialaIndia
  2. 2.Department of PhysicsMaharishi Markandeshwar UniversityMullana, AmbalaIndia

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