Abstracts Book - IMRC 2018

• SC4-P013
COMPARATIVE STUDY OF OPTICAL AND MICROSTRUCTURAL
PROPERTIES OF THIN FILMS OF NIALOX-ALXOY OBTAINED BY
AACVD, WITH APPLICATION IN SOLAR HEATERS
Carlos Alberto Hurtado Arambula 1 , Rubén Dorantes Rodríguez 1 , Roberto Tito Hernández
López 1 , Beatríz Cruz Muñoz 2 , Humberto González Bravo 1 , Mario Miki Yoshida 3 , Patricia
Amézaga Madrid 3 , Pedro Pizá Ruiz 3 , Mauro Santelis Carbajal 1
1 Universidad Autónoma Metropolitana, Ciencias Básicas e Ingeniería, Mexico. 2 Universidad
Tecnológica de Pereira, Departamento de Física, Colombia. 3 Centro de Investigación en
Materiales Avanzados, S.C., Física de Materiales, Mexico.
Thin films of NiAlOx-AlxOy Al and Ni nitrates were deposited on aluminum
substrates with different surface treatments (chemical, polishing and surface
roughing by sand blast), by means of the aerosol-assisted chemical vapor
deposition technique (AACVD). The deposit was made in two steps, first an Al2O3
film was obtained and the NiAlOx film was grown on it. The deposits were made
at the temperatures of the aluminum substrate of 400°C and 450°C, varying the
molar concentration and the nickel aluminum ratio. From the micrographs
obtained by SEM it was observed that, for the temperature of 400°C, the
morphology presented by the coatings was granular with few pores, without
cracks and areas with amorphous formations in which nickel accumulated. The
EDX studies indicated that the film was composed of O, Ni and Al and the
chemical composition was dependent on the temperature of the substrate. The
absorption graphs obtained by UV-Vis spectrometry in the wavelength range
200 to 2500 nm, indicated that the variation in the molar concentration of the
precursor solutions generates a variation in the optical properties of the coating.
The solar selective films of NiAlOx-AlxOy deposited, had a solar absorption α =
0.43 - 0.71 and a thermal emittance, measured with infrared thermography, of
ε = 0.11 - 0.13 (30°C to 150°C), depending on the conditions of deposit. The
results of the comparative study showed that the optical properties of the
NiAlOx-AlxOy films strongly depend on the deposition temperature and the
surface characteristics of the substrate used, polished substrates showing the
best results.
Acknowledgment:
The authors thank the “Fondo de Sustentabilidad Energetica CONACYT-
SENER” for the financial support to develop this project. We also thank M. Oscar
Solís Canto, Eng. Diana Vázquez and Alejandro Román Loya the “Laboratorio