Synthesis and characterization of silver vanadates thin films for photocatalytic applications
Por:
Gonzalez-Zavala, F., Escobar-Alarcon, L., Solis-Casados, D. A., Espinosa-Pesqueira, M., Haro-Poniatowski, E., Rodriguez-Castellon, E., Rodriguez-Aguado, E.
Publicada:
1 may 2018
Resumen:
Silver vanadates thin films were deposited by a hybrid deposition system
combining laser ablation and thermal evaporation. A high purity vanadium
target was ablated using the third harmonic of a Nd:YAG laser whereas
high purity silver pellets were evaporated. The as-deposited thin films
were subjected to thermal treatments at 400 degrees C to obtain
crystalline films. For films without Ag amorphous V2O5 thin films were
deposited and as the Ag is incorporated in the material different silver
vanadates were obtained. The effect of the silver load on the
composition, structure, optical properties, surface morphology and
photocatalytic response of the deposited films was studied. The film
composition, determined by X-ray photoelectron spectroscopy, reveals Ag
contents from 5.5 to 18.9 at.%. The crystalline phases formed were
identified by micro-Raman Spectroscopy; the results indicate the
formation of three silver vanadates depending on the silver content. The
morphology was observed using scanning electron microscopy, the films
surface changes from a smooth surface to belts covering the surface and
finally Ag nanoparticles are observed at the higher Ag contens. Optical
properties determined from UV-vis reveal the presence of the surface
plasmon signal in films containing silver. The films were tested in the
photocatalytic degradation of Malachite Green dye reaching maximum
degradations degrees close to 53% under solar irradiation. Reactive
species trapping experiments suggest that O-2(-)center dot produced by
the O-2 reduction via the photogenerated electrons drives the
photodegradation mechanism.
Filiaciones:
Gonzalez-Zavala, F.:
Inst Nacl Invest Nucl, Dept Fis, Apdo Postal 18-1027, Mexico City, DF 11801, Mexico
UNAM, UAEM, Ctr Conjunto Invest Quim Sustentable, Toluca 50200, Estado De Mexic, Mexico
Univ Autonoma Estado De Mexico, Programa Posgrad Ciencia Mat, Toluca 50000, Estado De Mexic, Mexico
Inst Nacl Invest Nucl, Dept Fis, Apdo Postal 18-1027, Mexico City 11801, DF, Mexico
Escobar-Alarcon, L.:
Inst Nacl Invest Nucl, Dept Fis, Apdo Postal 18-1027, Mexico City, DF 11801, Mexico
Inst Nacl Invest Nucl, Dept Fis, Apdo Postal 18-1027, Mexico City 11801, DF, Mexico
Solis-Casados, D. A.:
UNAM, UAEM, Ctr Conjunto Invest Quim Sustentable, Toluca 50200, Estado De Mexic, Mexico
Espinosa-Pesqueira, M.:
Inst Nacl Invest Nucl, Dept Tecnol Mat, Apdo Postal 18-1027, Mexico City 11801, DF, Mexico
Haro-Poniatowski, E.:
Univ Autonoma Metropolitana Iztapalapa, Dept Fis, Apdo Postal 55-534, Mexico City, DF, Mexico
Rodriguez-Castellon, E.:
Univ Malaga, Fac Ciencias, Dept Quim Inorgan, Malaga 29010, Spain
Rodriguez-Aguado, E.:
Univ Malaga, Fac Ciencias, Dept Quim Inorgan, Malaga 29010, Spain
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