radual and selective achievement of Rutile-TiO2 by thermal annealing amorphous TixOyNz film

Autor(es)

Zanatta, A. R. ^[1] ; Echeverrigaray, F. G. ^[2] ; Cemin, F. ^[2] ; Alvarez, F. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Fis Sao Carlos, BR-13560970 Sao Carlos, SP - Brazil

^[2] Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Non-Crystalline Solids; v. 579, MAR 1 2022.
• Citações Web of Science: 0

Resumo

To a large extent, future technological progress relies on the study-development of advanced materials with new and/or improved properties. The semiconductors titanium oxynitride (TixOyNz) and titanium dioxide (TiO2) perfectly meet these requirements in the sense that their main chemical and structural properties can be customized, leading to successful contributions in optics, electronics, catalysis, bactericides surfaces, and photovoltaics applications, for instance. Motivated by these aspects, this paper reports on the structure and optical bandgap of TixOyNz, as obtained by Raman scattering and optical transmittance spectroscopy, respectively. The study comprises a set of films produced by N-2-plasma Ti sputtering and subsequently thermal annealed in an atmosphere of oxygen flux. As the thermal treatments advance, the Raman spectra indicate a gradual transformation of the films from amorphous+(nano/micro-)crystalline TixOyNz to the crystalline Rutile phase of TiO2 (R-TiO2). Consistent with these structural changes, the optical bandgap of the films decreases from - 3.2 to 2.5 eV, i.e., across part of the ultraviolet-blue spectral region. The analysis of the experimental data confirms the importance of nitrogen (in the early stages of sample preparation) on the achievement of R-TiO2 in a continuous and controllable way. Therefore, this paper shows the suitability of the TixOyNz compound to produce films with well-defined crystalline TiO2-related structures and specific optical bandgap values. (AU)

• Processo FAPESP: 18/24461-0 - Estudo e desenvolvimento de filmes finos de ligas de alta entropia (LAE-F)
• Beneficiário: Felipe Cemin
• Linha de fomento: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 19/00757-0 - Estudo e controle das orientações cristalinas em heterojunções MoS2/TiO2 e MoS2/TiO2:H e seus efeitos sobre suas propriedades físico-químicas
• Beneficiário: Fernando Graniero Echeverrigaray
• Linha de fomento: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 19/18460-4 - Desenvolvimento e propriedades termomecânicas e tribológicas de materiais multicomponentes avançados de alta entropia
• Beneficiário: Fernando Alvarez
• Linha de fomento: Auxílio à Pesquisa - Regular