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

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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Kayra, Seda; Altan, Hakan; Department of Physics (2011)
In this thesis, Terahertz Time-Domain spectroscopy (THz-TDS) was used in order to measure the electrical properties of silicon solar cells. The advantage of THz-TDS is that it allows us to measure the electrical properties without electrical contacts. In order to perform these measurements, a reflection based system was constructed and the changes in the peak amplitude in the time-domain under a, 450mW 808 nm continuous wave laser source were measured. The solar cell that was used in this thesis was manufac...
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Radfar, Behrad; Turan, Raşit; Yerci, Selçuk; Department of Micro and Nanotechnology (2019)
Surface of crystalline silicon solar cell plays an important role in its performance. It affects the optical properties which can be determined by surface’ reflectance. To minimize the reflection from the flat surface, thus, improve light trapping, the crystalline silicon wafers must be textured. Through the texturing process, roughness is introduced at the surface, so the incident light has a larger probability of being absorbed into the solar cell. Monocrystalline silicon solar cells can typically be text...
Synthesis, electrochemical characterization and organic solar cell applications of selenophene containing conjugated polymers
Yaşa, Mustafa; Toppare, Levent Kamil; Department of Polymer Science and Technology (2017)
Donor-Acceptor (D-A) type conjugated polymers are very popular for potential applications such as organic light emitting diodes, solar cells, electrochromic devices and organic field effect transistors. In literature, cyclopentadithiophene and its derivatives are commonly used electron donor units for organic solar cells. The incorporation of selenium atom into polymer backbone results in low band gap polymers as compared to sulfur and oxygen counterparts. In this study, selenophene containing conjugated po...
A Feasibility study for external control on self-organized production of plasmonic enhancement interfaces for solar cells
Zolfaghari Borra, Mona; Bek, Alpan; Ünalan, Hüsnü Emrah; Department of Micro and Nanotechnology (2013)
The present study is about the improvement of the energy conversion efficiency of solar cells in which plasmonic light-trapping approach has been investigated. In this study, metal nanoparticles are allowed to form in a self-organized fashion on both flat and textured full scale monocrystalline silicon solar cell. These metal nanoparticles with strong optical interaction cross-sections at localized plasmonic resonance energies, improve coupling of the incoming light into the active area of solar cells by wa...
Structural characterization of intrinsic a-Si:H thin films for silicon heterojunction solar cells
Pehlivan, O.; Yilmaz, O.; Kodolbas, A. O.; Duygulu, O.; Tomak, Mehmet (2013-01-01)
We have utilized ex-situ spectroscopic ellipsometry and HRTEM to characterize the optical and structural properties of intrinsic a-Si:H thin layer that plays a key role for the improvement of the open circuit voltage in silicon heterojunction solar cells. Intrinsic a-Si:H films were deposited on (100) p-type CZ silicon wafers by using Plasma Enhanced Chemical Vapor Deposition (PECVD) technique at 225 degrees C substrate temperature and deposition time ranges from 15 s to 1800 s. Observed changes in the imag...
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.