HETEROGENEOUS PHOTOCATALYTIC AND PHOTOSYNTHETIC DEPOSITION OF COPPER ON TIO2 AND WO3 POWDERS

The deposition of Cu from aqueous solutions on suspensions of TiO2 and WO3 under irradiation with a xenon lamp is reported. Deposition in the photosynthetic mode (Cu2+ 4- H2O + 2hv → Cu + 1/2O2 + 2H+) led to removal of as much as 83% of the Cu(II) from a solution containing 4.2 μg of Cu/mL. In the presence of acetate the reaction is photocatalytic (Cu2+ + 2CH3COO- + 2hv → Cu + C2H6 + 2CO2). A comparison is made between the photoprocesses at powders and the photoelectrochemical behavior at single crystal semiconductor electrodes. © 1979 American Chemical Society.