Phase Manipulation on Tio2-Based Photocatalyst  For Solar Reduction of Cu

Abstract

Solar energy is abundant and economic, showing great attraction to the high-power consumption industries such as metallurgy. In this work, aiming at utilization of solar energy for photo-metallurgy, TiO2 nano-film were used as photocatalysts to reduce Cu2+ ions in ethanol-copper acetate aqueous solution by photocatalytic reduction. Cu and Cu2O was successfully prepared as confirmed by XRD, XPS and SEM/EDS. By comparing anatase and mixed phase TiO2, better photoreduction performance was confirmed in pure anatase-based phtocatalyst. By altering the copper concentration in precursor solution, different mixture of Cu, Cu2O and CuO was obtained. The feasibility was analyzed according to Pourbaix diagram, and photoreduction mechanism was proposed. This work proves the feasibility of utilizing photogenerated electrons as reducing agent in metallurgy, which may shed some light in the solar energy-based photo-metallurgy investigation.

Keywords: photo-metallurgy, Photocatalytic reduction, copper deposition, Titanium dioxide, anatase film