Surface coverage control of self organized plasmonic nanostructures at interfaces of photovoltaics related materials

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2017
Birant, Gizem
In this thesis, it has been demonstrated that light management in photovoltaic devices might be achieved via plasmonic interfaces. New strategies have been developed to achieve a 10% surface coverage ratio that is ideal for light management. First, metal nanoparticles are synthesized as colloidal solutions. Metal nanoparticles are preferred because when they are coated on the surface of the solar cell, they increase the optical path length of the light in the cell via interacting and scattering the incident light. In this study, silver nanoparticles have been chosen considering their strong resonance characteristics and their low cost compared to gold. The industrial scale solar cells with surface roughness due to saw damage etching are coated with colloidal silver nanoparticle solution by a spray gun. Then heat treatment is applied on these surfaces to form the plasmonic interfaces. In order to examine the localized surface plasmon resonance properties of silver nanoparticles, silicon solar cells are produced in three different thickness levels of silicon nitride ({u1D446}{u1D456}3{u1D441}4). Then, the nanoparticle solution is spray coated by different numbers of passes on the aforementioned silicon solar cells with different thickness levels. Via this study, the effect of the number of spray passes on localized surface plasmon resonance is observed. After the spray coating step, the specular reflectance, diffuse reflectance, haze and quantum efficiency measurements are made. The optical and electrical properties of the nanoparticles are determined by these measurements. With the aid of a solar simulator, improvements in the efficiencies of full-scale solar cells are identified. As a result of the spray coating method, it has been observed that the increase in efficiency of the solar cells depend both on the number of spray passes and on the structure of the solar cells used. By developing this study, the efficiencies of full-scale silicon solar cells can be increased beyond the known limits by also controlling the production steps of the cells. In this context, this work can be used as a roadmap.

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Citation Formats
G. Birant, “Surface coverage control of self organized plasmonic nanostructures at interfaces of photovoltaics related materials,” M.S. - Master of Science, Middle East Technical University, 2017.