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Information × Registration Number 0226U003176, (0124U000760) , R & D reports Title Effective nanocrystalline materials based on metal chalcogenides for optoelectronic systems popup.stage_title Розроблення фізико-хімічних основ технології одержання нанокристалічних матеріалів на основі халькогенідів металів (CdTe, CdSe, CdS). Head Kashuba Andrii I., Кандидат фізико-математичних наук Registration Date 19-03-2026 Organization Lviv Polytechnic National University popup.description1 Development of physicochemical bases of technology for obtaining and investigating the energy and optical properties of nanocrystalline metal chalcogenide compounds (CdTe, CdSe, CdS, and solid solutions based on them) for high-efficiency solar cells. popup.description2 Studies of non-stoichiometric CdmXn clusters (m≠n, X=Te, Se and S) were carried out and the position of the HOMO–LUMO gap, binding energy and electronegativity were obtained. It was found that CdmXn clusters with a higher cadmium content (m/n > 1) have larger average Cd–X bond lengths. It was shown that the solvent does not affect the position of the HOMO–LUMO gap, and its value increases as the m/n ratio approaches 1. It was found that samples with m/n ≤ 1 are more stable. The optical properties of CdTe nanoparticles in water and on a quartz substrate were calculated. As CdTe content decreases, transmission and reflection increase, while the refractive index and extinction coefficient decrease. The dielectric constant, the ratio of the carrier density to their effective mass, and the relaxation time were obtained. According to the Mie theory, the optical properties of CdTe nanoparticles with sizes (R) ranging from 1 to 100 nm were investigated in liquid and solid matrices. When light interacts with small CdTe nanoparticles (R < 30 nm), absorption prevails, and with large ones, scattering. The maximum values of Qext, Qsca, and Qabs at λ < 380 nm were obtained for CdTe nanoparticles with R = 30 nm in water and at λ > 380 nm for SiO2. CdS films on glass substrates were obtained by chemical surface deposition, and CdSe films on quartz substrates were obtained by magnetron sputtering. The optimal composition and nanocrystalline structure were established. The band gap and Urbach energy decrease with increasing film deposition time. The properties of the Au/CdTe/CdS/ITO heterojunction have been investigated. The maximum efficiency is observed at 600–800 nm. Increasing the CdTe thickness to 4 μm increases the current density and open circuit voltage (over 1.05 V). The optimal layer thicknesses have been determined: 150–200 nm for the contact, 50–100 nm for CdS and 3–4 μm for CdTe. Product Description popup.authors Ihor Semkiv Myron Rudysh Rostyslav Yavorskyi Natalia Kashuba Liliia Deva popup.nrat_date 2026-03-19 Close