Synthesis of (CZTS) Cu2ZnSnS4 Nanoparticles by Hydrothermal Method for Solar Cell Application

Traditional photovoltaic devices for replacing fossil fuels have problems, including high construction and installation costs. Hence, there is now more focus on the new generation of solar cells, including solar tiles with higher efficiency and lower const. Due to the emergence of nanolayers and the extensive advances in the selection of raw materials and devices for the application of this type of layers, in the present study, the preparation and achievement of optimal conditions for the main layer of solar tile has been considered. The best sample containing adsorbent layer film ink was obtained from CZTS and was made by solothermal method at 550 ºC. Using X-ray diffraction (XRD) and Raman spectroscopy analysis, phase studies of the synthesized samples as well as the identification of functional groups in the compounds were performed. Field emission scanning electron microscopy (FESEM) was used to study the surface morphology and the microstructure of the prepared inks. A UV-Vis spectrophotometer was used to analyze the ultraviolet-visible absorption spectrum. XRD analysis showed the formation of pure cassiterite as well as the presence of secondary phases of CZTS in some samples. and the results were confirmed by Raman spectroscopy. In the studies, the sample synthesized at 550 ºC with crystalline structure of cassiterite with suitable peak intensities was selected as the most suitable sample. FESEM microscopy showed that all samples of CZTS nanoparticles had a petal-like shape and with increasing temperature the petals bended. Finally the best conditions for the homogeneity of the morphological particles of the sample were observed at 550 ºC. Also, based on the results of the EDS, the sample with the highest weight percentage of copper and the lowest weight percentage of sulfur had priority in terms of application in solar cell structures, such characteristics were observed in the sample synthesized at 550 ºC. UV-Vis results showed that the optical cleavage band of CZTS nanoparticles in the best sample was 1.49 eV. In general, the results of the studies in this work showed the appropriateness of the solothermal synthesis method and also the effect of temperature on the final characteristics of the thin film, including the type of structure, morphology, transmition and energy bandgap.