Detalhes do Documento

Black chromium is an important coating material used in solar thermal systems as a spectrally selective surface. This coating is usually obtained by electrodeposition from sulphate free chromium (VI) aqueous solutions which represent a health and environmental hazard due to the presence of Cr(VI), a known toxic and carcinogenic agent. Recent developments in green chemistry have shown that ionic liquids can be used as electrolytes, allowing the deposition of a wide range of materials with negligible environmental and health impacts. In the present study, the electrodeposition of black chromium films from a solution of ionic liquid containing chromium (III) has been investigated by cyclic voltammetry and chronoamperometry. Homogeneous and well adherent black Cr films have been obtained on several substrates, by potentiostatic electrodeposition. The films morphology and composition have been characterised by SEM/EDS and GI-XRD.