Production and characterization of Ag2S/CU2S/PbS quantum dot sensitized solar cells

Low cost, relatively easy production and the prospect of high efficiency make the quantum dots sensitized solar cells very attractive in photovoltaic cell production. In this thesis, two separate studies were conducted. In the first study, Ag2S quantum dots monolayer and three successive layer (tandem) solar cells were produced by using consecutive ionic layer adsorption and reaction (SILAR) technique and investigated in terms of optical and electrical properties. In the Tandem cell, the three-layer TiO2 coating was cycled to 5, 4, 3 SILAR, respectively. When the Uv-vis spectra of single layer cells in the 300-1200 nm band range were examined, it was observed that the SILAR cycle number increased and the absorbance value of the samples increased. Compared to single-layer solar cells, the absorbance value of the Tandem structured solar cell was found to be greater. With increasing SILAR number, it was determined that the band gap of the solar cells decreased from 3.31 eV to 1.41 eV under the 100 mW / cm2 solar simulator, the I-V graphics of the solar cells were drawn and the highest efficiency was obtained for 5 SILAR cycle solar cells for single layer cells from this graph. It is concluded that the efficiency of tandem solar cell is higher than that of single layer 4 and 3 SILAR cycle solar cells and equal to approximately 5 SILAR cycle solar cells. In the second study, Ag2S, Cu2S and PbS quantum dot structures were used in solar cells. Various combinations of these quantum dot structures were collected on single layer TiO2 in different SILAR cycle. The band gap of sample were observed to decrease from 3.48 eV to 2.85 eV for solar cell coated with Cu2S quantum dots and from 3.46 eV to 2.15 eV for solar cell coated with PbS quantum dots with increasing SILAR number. I-V measurements were made under 100 mW/cm2 solar simulator and it was concluded that the use of PbS quantum dot structures together with Ag2S quantum dot structures resulted in a decrease in efficiency, and that the use of Cu2S quantum dot structures together with Ag2S quantum dot structures provides a significant increase in efficiency.