White light generation from the CdSe ZnS core-shell
Other Title(s)
توليد الضوء الأبيض من سيلينايد الكادميوم كبريتيد الزنك لب-قشرة
Dissertant
Thesis advisor
University
University of Baghdad
Faculty
College of Science
Department
Department of Physics
University Country
Iraq
Degree
Master
Degree Date
2011
English Abstract
The CdSe/ZnS core-shell nanocrystals (NCs) were prepared by the chemical method.
The cadmium selenide was prepared as a colloidal solution from reaction of sodium selenosulfide (Na2SeSO3) and cadmium chloride (CdCl2) with gelatin solutions at 1:2 mole ratio.
The zinc sulfide was prepared by chemical reaction of zinc chloride (ZnCl2) and sodium sulfide (Na2S) at 1:1 mole ratio.
The nanocrystals dimensions and shapes are controlled by the chemical reaction time.
The structure, optical properties and the surface morphology were studied.
The optical energy gaps were determined by several techniques from the absorption spectrum and luminescence spectrum.
The values of 2.38 and 3.77 eV for CdSe and ZnS were found from the Tauce relation, whereas the energy gap values from the photoluminescence spectrum were found to be about to 2.38 and 4.00 eV for CdSe, ZnS respectively.
The generation of the white light from the CdSe/ZnS core-shell nanocrystals illuminated by GaN UV−LED is presented.
The CdSe/ZnS coreshell nanoparticles prepared by the chemical method were dispersed in Polyamide nylon to prepare the composite films.
The generation of white light was found from illumination the CdSe/ZnS core-shell composite film by UV−LED of power 5mW at wavelength (λ=365 nm).
The white light generation mechanism was analyzed depending on the colors mixing from the illuminated CdSe/ZnS core-shell nanoparticles.
The chromaticity coordinates of the generated white light was measured by the photoluminescence spectrum, which were located at x=0.40, y=0.43 and x=0.39, y=38 for colloidal and composite films of CdSe/ZnS core-shell respectively.
The correlated colour temperature was found to be about 3886 and 4105 K for colloidal and composite films of CdSe/ZnS core-shell respectively.
Main Subjects
No. of Pages
93
Table of Contents
Table of contents.
Abstract.
Abstract in Arabic.
Chapter One : Introduction and basic concepts.
Chapter Two : The experimental work.
Chapter Three : Results and discussion.
References.
American Psychological Association (APA)
Kazim, Aqil Mahdi. (2011). White light generation from the CdSe ZnS core-shell. (Doctoral dissertations Theses and Dissertations Master). University of Baghdad, Iraq
https://search.emarefa.net/detail/BIM-607604
Modern Language Association (MLA)
Kazim, Aqil Mahdi. White light generation from the CdSe ZnS core-shell. (Doctoral dissertations Theses and Dissertations Master). University of Baghdad. (2011).
https://search.emarefa.net/detail/BIM-607604
American Medical Association (AMA)
Kazim, Aqil Mahdi. (2011). White light generation from the CdSe ZnS core-shell. (Doctoral dissertations Theses and Dissertations Master). University of Baghdad, Iraq
https://search.emarefa.net/detail/BIM-607604
Language
English
Data Type
Arab Theses
Record ID
BIM-607604
