Physical properties and phase transition observed in vanadium oxide thin films deposited by RF magnetron sputtering
Por:
Acosta, Dwight, Chavez-Esquivel, G., Magana, Carlos, Hernandez, Francisco, Perez-Pacheco, A., Huerta, L.
Publicada:
1 may 2019
Resumen:
In this work, we focus on the study of structural and electrical properties of vanadium oxide thin films synthesized by RF magnetron sputtering. The samples were deposited on glass at 0%, 5%, 10% and 20%, O 2 concentration inside the vacuum of the chamber. The films were characterized by x-ray Photoelectron Spectroscopy (XPS), Scanning Electron Microscopy (SEM), Conventional and High Resolution Transmission Electron Microscopy (CTEM and HRTEM, respectively), UV-vis Spectroscopy and Cyclic Voltammetry (CV). The increase in oxygen concentration induces agglomeration behaviour atmospheric-deposition-dependent on film characteristic surface, this phenomenon in turn, influences its structural and electrical properties. A reducing atmosphere enabled the formation of V 2 O 5 to VO 2 phases, respectively, the mixed-valence of V 5+ and V 4+ related with V 2 O 5 and VO 2 system were established. The existence of V 2 O 5 and VO 2 on the surface film is supported by x-ray photoelectron spectroscopy analysis. The reduction process in substrate surface was detected from 10%, content of O 2 which showed a local minimum associated with agglomeration of V-oxide in the surface substrate, and a possible heterostructure configuration. The electrochemical response showed a minimum in diffusion cathodic associated to kinetic phenomena of double layer. However, the diffusion anodic was constant, associated to rapid electronic transfer and maximum coloration efficiency during electrochromic experiment. The co-existence phases on the surface films generates electrochromic and thermochromic behaviour. © 2019 IOP Publishing Ltd.
Filiaciones:
Univ Nacl Autonoma Mexico, Inst Fis, Apdo Postal 20-364, Mexico Cdmx, Mexico
Univ Autonoma Metropolitana Azcapotzalco, Div Ciencias Basicas & Ingn, Av San Pablo 180, Ciudad De Mexico 02200, Mexico
HGM, UIDT, Doctor Balmis 148, Col Doctores Cuahutemoc 06726, Mexico
Univ Nacl Autonoma Mexico, Inst Invest Mat, Apdo Postal 70-360, Mexico Cdmx, Mexico
Instituto de Fisica, Universidad Nacional Autónoma de México, Cd. Universitaria, México CDMX, Apdo. Postal 20-364, Mexico
División de Ciencias Básicas e Ingenieria, Universidad Autónoma Metropolitana Azcapotzalco, Col. Reynosa Tamaulipas, Av. San Pablo 180, Azcapotzalco, Ciudad de México, 02200, Mexico
Unidad de Investigación y Desarrollo Tecnológico (UIDT-HGM), Hospital General de México, Doctor Balmis 148, col. Doctores. Del. Cuahutemoc, C. P 06726, Mexico
Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Cd. Universitaria, Apdo. Postal 70-360, México CDMX, Mexico
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