RT Journal Article T1 Enhanced UV emission of Li-Y co-doped ZnO thin films via spray pyrolysis A1 Bazta, Otman A1 Urbieta Quiroga, Ana Irene A1 Piqueras De Noriega, Francisco Javier A1 Fernández Sánchez, Paloma A1 Addou, Mohammed A1 Calvino, J. J. A1 Hungría, A. B. AB Pure ZnO and ZnO: 2%Y:x%Li (x = 0, 3, 5 and 7 at.%) thin films have been successfully prepared onto glass substrates under optimized conditions by spray pyrolysis technique at 450 ºC and their suitability for the fabrication of efficient optoelectronic devices is demonstrated. The samples have been characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), UV-Visible absorption spectroscopy photoluminescence (PL) and Raman spectroscopy (RS), in order to investigate the effect of Y-Li co-doping on the structure, surface morphology, and optical features of the thin films. The films crystallized into a hexagonal structure, with a preferred orientation along the c-axis. No additional phases have been observed. SEM micrographs showed that Y and Li co-doping plays a key role in the grain size and morphology of the films. The optical study via transmittance and absorption measurements within the UV-vis region revealed that the films are highly transparent (82-90%). The optical bandgap (E-g) depends on the concentration of lithium added, which is explained by the Burstein-Moss (BM) effect. The PL measurements at room temperature under excitation with 325 nm wavelength, showed an appreciable improvement of ultraviolet emission by increasing the Li co-doping concentration. This enhancement reaches a maximum at 5 at.% Li content, and decreases after further increase in Li content. Raman scattering spectra were also carried out and revealed the presence of the wurtzite phase of ZnO exclusively. (C) 2019 Elsevier B.V. All rights reserved. PB Elsevier Science SA SN 0925-8388 YR 2019 FD 2019-11-05 LK https://hdl.handle.net/20.500.14352/5961 UL https://hdl.handle.net/20.500.14352/5961 LA eng NO ©2019 Published by Elsevier BVThis work was supported by MINECO/FEDER (MAT 2016-81118-P and MAT 2015-65274-R). O. B. thanks Aula del Estrecho fellowship. NO Ministerio de Economía y Competitividad (MINECO) / FEDER DS Docta Complutense RD 6 abr 2025