Search academic texts

Information × Registration Number 0224U001783, 0121U108649 , R & D reports Title Effective thin-film gas sensors based on compounds of group АIIВVI popup.stage_title Head Kashuba Andrii І., Кандидат фізико-математичних наук Registration Date 30-01-2024 Organization Lviv Polytechnic National University popup.description2 Optimal modes of deposition of thin films of CdSe, CdS, ZnO and solid substitution solutions of ZnO:Al, CdSe1-xSx were worked out. The dependence of the band gap width on the film thickness was determined. For the first time, the electron-optical parameters were estimated within the framework of the Drude free electron model for films. Doping zinc oxide films with aluminum leads to an increase in optical mobility, relaxation time, and plasma frequency. For the first time, the dependence of the ratio of carrier density to the effective mass of the carrier on the thickness of the CdSe films was estimated. Energy spectra and optical parameters of CdSe1-xSx films were calculated for the first time. The same calculations were carried out for the case when the films interact with CO, NO2 and H2 gases. The interaction of CdSe1-xSx films with CO gas affects the band gap and the spin-orbit splitting parameter. The greatest effect of CO adsorption on spin-orbit splitting was found for the binary compound CdS (ie, concentration x= 1). For all studied CdSe1-xSx complexes, in the case of interaction with H2, we see the tendency Eg(Se+H2) > Eg(S+H2). Differences in band gap values allow the use of CdSe1-xSx thin films as gas sensors. The greatest effect of NO2 adsorption on the optical gap was found for CdSe0.50S0.50. The absolute value of Ead for CdSe0.75S0.25 (for the case where nitrogen interacts with sulfur) and CdSe is the largest. The value of the calculated adsorption energies of molecules shows the following trend Ead(S+H2) > Ead(Se+H2). The technology of doping ZnO thin films with rare earth elements has been developed. ZnO:Re (Re= Cd+Cl; Cd+Eu+Cl; Er+Cl; Yb; Tb; Sm and Nd) thin films were synthesized and investigated. For the first time, a study of low-frequency reflection spectra for ZnO:Re films was conducted. A laboratory sample of the gas sensor was developed based on the tested materials. Product Description popup.authors Ivashchyshyn Fedir O. Vashchynskyi Vitalii M. Guminilovych Ruslana R. Dzikovskyi Viktor Ye. Kashuba Natalia Yu. Kovalenko Mariia V. Kunyo Vasyl M. Maly Taras S. Pershyna Sofiya A. Rudysh Myron Ya. Semkiv Ihor V. Storozhuk Yaroslav M. Shyshkovskyi Serhii V. Shchepanskyi Pavlo A. popup.nrat_date 2024-01-30 Close