USING QUANTUM DOTS IN THE CREATION OF POLYMER FLUORESCENT SOLAR CONCENTRATORS

A.A. Lang, N.K. Shautenbaeva,
A.I. Mantel, I.S. Irgibaeva
Eurasian National University n.a. Gumilyev, Astana, Kazakhstan

USING QUANTUM DOTS IN THE CREATION OF POLYMER FLUORESCENT SOLAR CONCENTRATORS

In modern life, many have heard of the growing need for alternative energy sources, which are more environmentally friendly and more efficient than to depletable coal, oil and gas. One such source is solar energy used due to solar cells by converting it into electricity. In solar cells as a power converter are used organic luminophors. Recently, there are many publications on the use of semiconductor quantum dots as a luminophor in a fluorescent solar concentrator (FSC) [1 - 3]. Quantum dots, as compared with organic luminophores have higher photostability to ultraviolet light. Among other things, they are much wider absorption spectra and capture the visible and ultraviolet region of the solar spectrum - depending on the size of the nanoparticles and their configuration [4].
The purpose of research is to obtain and determine optical properties of the polymer compositions of PMMA containing quantum dots of CdS.
At the initial stage of research it was worked out the methodic of obtaining of the dispersion of cadmium sulfide quantum dots (QDs CdS) in methyl methacrylate (MMA). By this method cadmium sulfide is obtained by passing hydrogen sulfide through a solution of cadmium acetate in dimethylformamide. As a result is formed saturated bright green colored transparent suspension [5]. The resulting suspension was centrifuged by adding methyl methacrylate in an amount of 100 μl of the suspension to 3 ml MMA. Obtained samples were characterized by fluorescence spectrum with a peak at 600 nm, which is characterized by very low intensity, and did not have clearly defined contour. This indicates a wide variation of CdS QDs size [6].
Next, we studied the effect of degree of polymerization, and consequently an effect of the viscosity of the dispersion on the fluorescence quantum dots. For this, initial solution of cadmium acetate in MMA was heated in a water bath at a specific temperature. At regular intervals, a sample solution and the hydrogen sulfide was passed there through and then removed from the resulting dispersions fluorescence spectra. After some time, the polymerization solution of cadmium acetate in MMA has become too viscous, which prevented further measurements of fluorescence. As the polymerization of methyl methacrylate with embedded quantum dots is gradually cadmium sulfide quenching fluorescence wavelength region while increasing the fluorescence wavelength region, which means the destruction of the quantum dots during the polymerization and the need to stabilize the cadmium sulfide quantum dots [7, 8].

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