Nanocomposite Bi/TiO2 multilayer thin films deposited by a crossed beam laser ablation configuration

• Published in: Applied physics. A, Materials science & processing Vol. 127; no. 11
• Main Authors: Martínez-Chávez, L. A., Esquivel, K., Solis-Casados, D. A., Velázquez-Castillo, R., Haro-Poniatowski, E., Escobar-Alarcón, L.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.11.2021; Springer Nature B.V
• Subjects: Applied physics; Bismuth oxides; Bismuth trioxide; Characterization and Evaluation of Materials; Condensed Matter Physics; Configurations; Electronic structure; Electrons; Emission spectra; Laser ablation; Lasers; Machines; Manufacturing; Materials science; Multilayers; Nanocomposites; Nanoparticles; Nanostructure; Nanotechnology; Optical and Electronic Materials; Optical properties; Photoelectrons; Photoluminescence; Physics; Physics and Astronomy; Processes; Pulsed laser deposition; Pulsed lasers; Raman spectroscopy; Spectrum analysis; Substrates; Surfaces and Interfaces; Thin Films; Titanium dioxide; X ray photoelectron spectroscopy; Multilayers; Laser ablation; Nanocomposites; Titanium oxide
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-021-04957-0

A crossed beam pulsed laser deposition configuration was used to prepare nanocomposites Bi/TiO 2 thin films on two different substrates. The multilayered system was formed by depositing TiO 2 and Bi layers alternately. In order to embed the Bi nanostructures in TiO 2, the subsequent TiO 2 layers were synthesized using a constant number of laser pulses (3000) corresponding to a thickness of approximately 21 nm. The Bi nanostructures were deposited on the TiO 2 layers alternately by irradiating the Bi target with 30, 100, 200, and 300 laser pulses. In this way, the Bi nanostructures were embedded inside the TiO 2 matrix. A total of 8 samples with bismuth and one reference, with TiO 2 only, were produced. Transmission Electron Microscopy (TEM) showed that nearly spherical nanoparticles (NPs) were obtained at lower number of pulses, whereas at 300 pulses a quasi-percolated nanostructured Bi film was obtained. X-Ray Photoelectron Spectroscopy (XPS) revealed that the TiO 2 layers were not affected due to the bismuth presence. Raman Spectroscopy showed vibrational features characteristic of the rutile phase for the titania layer. The Raman spectrum of the multilayer prepared using 300 laser pulses on the bismuth, suggests that the Bi layer is formed by a mixture of metallic Bi, and α-Bi 2 O 3 . The Ultraviolet–Visible Spectroscopy reveals that no substantial changes are presented in the transmittance spectra indicating similar optical properties of the different deposits. Finally, the photoluminescence emission spectra indicate that the substrate position in the deposition chamber affects the electronic structure of the material.