Abstract

GONZALEZ, F.; BARRERA C., E.  and  ROSAS C., R.. Photothermal selective coatings of black molybdenum. Rev. Mex. Ing. Quím [online]. 2010, vol.9, n.1, pp.79-83. ISSN 1665-2738.

Thin and adherent coatings of molybdenum black solar selective coatings have been produced on copper substrates by immersion in solutions with different concentration of ammonium molybdate. The copper sheet was polished prior to immersion in the molybdate solution. XRD analyses showed that the coating consists of different oxides of copper and molybdenum. The maximum solar absorptance of the resulting molybdenum black coating was 0.87 for which the thermal emittance was 0.45. The best selectivity of 4.05 was obtained for a coating made in three days in an 8.0 mM solution of ammonium molybdate, for which the absorptance was 0.81 and thermal emittance, 0.2.

Keywords : solar selective coatings; optical properties; microstructural properties; chemical bath; molybdenum black.