Fluorescence relaxation dynamics of CdSe and CdSe/CdS core/shell quantum dots

doi:https://doi.org/10.1063/1.4872624

Title: Fluorescence relaxation dynamics of CdSe and CdSe/CdS core/shell quantum dots

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Abstract

Time-resolved fluorescence spectra for colloidal CdSe and CdSe/CdS core/shell quantum dots have been investigated to know their electron relaxation dynamics at the maximum steady state fluorescence intensity. CdSe core and CdSe/CdS type I core-shell materials with different shell (CdS) thicknesses have been synthesized using mercaptoacetic acid as a capping agent. Steady state absorption and emission studies confirmed successful synthesis of CdSe and CdSe/CdS core-shell quantum dots. The fluorescence shows a tri-exponential decay with lifetimes 57.39, 7.82 and 0.96 ns for CdSe quantum dots. The lifetime of each recombination decreased with growth of CdS shell over the CdSe core, with maximum contribution to fluorescence by the fastest transition.

Authors:

Kaur, Gurvir; Kaur, Harmandeep ^[1]

Centre of Advanced Study in Physics, Department of Physics, Panjab University, Chandigarh-160014 (India)

Publication Date:: 2014-04-24

OSTI Identifier:: 22269478

Resource Type:: Journal Article

Journal Name:: AIP Conference Proceedings

Additional Journal Information:: Journal Volume: 1591; Journal Issue: 1; Conference: 58. DAE solid state physics symposium 2013, Patiala, Punjab (India), 17-21 Dec 2013; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0094-243X

Country of Publication:: United States

Language:: English

Subject:: 77 NANOSCIENCE AND NANOTECHNOLOGY; CADMIUM SELENIDES; CADMIUM SULFIDES; ELECTRONS; EMISSION SPECTRA; FLUORESCENCE; FLUORESCENCE SPECTROSCOPY; INTERFACES; LIFETIME; QUANTUM DOTS; RECOMBINATION; RELAXATION; SYNTHESIS; TIME RESOLUTION

Citation Formats


                    Kaur, Gurvir, Kaur, Harmandeep, and Tripathi, S. K., E-mail: surya@pu.ac.in. Fluorescence relaxation dynamics of CdSe and CdSe/CdS core/shell quantum dots.  United States: N. p., 2014. 
        Web.  doi:10.1063/1.4872624.

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                    Kaur, Gurvir, Kaur, Harmandeep, & Tripathi, S. K., E-mail: surya@pu.ac.in. Fluorescence relaxation dynamics of CdSe and CdSe/CdS core/shell quantum dots.  United States.  https://doi.org/10.1063/1.4872624

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                    Kaur, Gurvir, Kaur, Harmandeep, and Tripathi, S. K., E-mail: surya@pu.ac.in. Thu .  
        "Fluorescence relaxation dynamics of CdSe and CdSe/CdS core/shell quantum dots".  United States.  https://doi.org/10.1063/1.4872624.

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@article{osti_22269478,

  title        = {Fluorescence relaxation dynamics of CdSe and CdSe/CdS core/shell quantum dots},

  author       = {Kaur, Gurvir and Kaur, Harmandeep and Tripathi, S. K., E-mail: surya@pu.ac.in},

  abstractNote = {Time-resolved fluorescence spectra for colloidal CdSe and CdSe/CdS core/shell quantum dots have been investigated to know their electron relaxation dynamics at the maximum steady state fluorescence intensity. CdSe core and CdSe/CdS type I core-shell materials with different shell (CdS) thicknesses have been synthesized using mercaptoacetic acid as a capping agent. Steady state absorption and emission studies confirmed successful synthesis of CdSe and CdSe/CdS core-shell quantum dots. The fluorescence shows a tri-exponential decay with lifetimes 57.39, 7.82 and 0.96 ns for CdSe quantum dots. The lifetime of each recombination decreased with growth of CdS shell over the CdSe core, with maximum contribution to fluorescence by the fastest transition.},

  doi          = {10.1063/1.4872624},

  url          = {https://www.osti.gov/biblio/22269478},
  journal      = {AIP Conference Proceedings},

  issn         = {0094-243X},

  number       = 1,

  volume       = 1591,

  place        = {United States},

  year         = {2014},

  month        = {4}

}

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