Photocatalytic Evaluation of TiO<sub>x</sub> Films Produced by Cathodic Arc-PVD with Silver Addition by UVC Photo-Reduction Method
Alma Yunuen Raya-Tapia,
Francisco Ung-Medina,
Guillermo César Mondragón-Rodríguez,
Eric Mauricio Rivera-Muñoz,
José Apolinar-Cortés,
Franklin J. Méndez,
Rafael Huirache-Acuña
Affiliations
Alma Yunuen Raya-Tapia
Facultad de Ingeniería Química, Universidad Michoacana de San Nicolás de Hidalgo, Francisco J. Múgica S/N, Ciudad Universitaria, Morelia 58060, Mexico
Francisco Ung-Medina
Potabilization Department, Water, Sewerage and Sanitation Operator Organization of Morelia, OOAPAS, OOAPAS, C. Manuel Carpio No.66, Morelia 58096, Mexico
Guillermo César Mondragón-Rodríguez
Conacyt, Center for Engineering and Industrial Development, CIDESI, Av. Playa Pie de la Cuesta No. 702, Desarrollo San Pablo, Santiago de Querétaro, Querétaro 76125, Mexico
Eric Mauricio Rivera-Muñoz
Centro de Física Aplicada y Tecnología Avanzada, Departamento de Nanotecnología, Universidad Nacional Autónoma de México, A.P. 1-1010, Santiago de Querétaro 76000, Mexico
José Apolinar-Cortés
Facultad de Ingeniería Química, Universidad Michoacana de San Nicolás de Hidalgo, Francisco J. Múgica S/N, Ciudad Universitaria, Morelia 58060, Mexico
Franklin J. Méndez
Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, CICATA Morelos, Instituto Politécnico Nacional, Boulevard de la Tecnología 1036 Z-1 P 2/2, Atlacholoaya 62790, Mexico
Rafael Huirache-Acuña
Facultad de Ingeniería Química, Universidad Michoacana de San Nicolás de Hidalgo, Francisco J. Múgica S/N, Ciudad Universitaria, Morelia 58060, Mexico
A titanium (Ti) commercial cathode material and high purity Ar and O2 were used in the cathodic arc physical vapor deposition (arc-PVD) process. The TiOx coating was deposited on the three sets of Raschig rings using decreasing ratios of Ar/O2:440/60, 400/100 and 300/100. The cross sections of the TiOx PVD coating were analyzed using field emission scanning electron microscopy (FE-SEM), X-ray energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). A homogeneous layer of Ti with small O content was observed, and the data suggest that a thin TiOx oxide film was deposited. For this reason, a thermal treatment was applied to the coating to oxidize it and form the rutile phase of TiO2 in the coating, which was demonstrated by grazing incidence XRD. In addition, the TiOx coatings absorb radiation, which was observed by diffuse reflectance band gap energy measurement. Silver (Ag) was added by the photo-reduction method, using UVC light to activate the TiO2 coating, and the band gap energy was analyzed by diffuse reflectance. The photocatalytic activities of the films were evaluated by degradation of the model dye rhodamine B and in the removal of fecal coliforms using two matrices, water from a secondary treatment effluent, and synthetic water.
