The composite membranes of zirconium oxide-cellulose acetate were prepared in a twostep procedure combining the phase-inversion method and deposition-hydrolysis technique. The first step allowed the preparation of membranes with different morphologies, and the second step allowed a highly dispersed metal oxide to be deposited on the membranes. The XPS O1s binding energy indicated that the interaction between the oxide and the cellulose matrix is probably of hydrogen bonding type. Phosphate retentions were 75 and 90% for the composite membrane in permeation experiments. The water fluxes for a pressure of 1.7 atm were (3.7 ( 1.7) × 10 -2 and (13.0 ( 2.1) × 10 -2 mL min -1 cm -2 . The membranes are very stable under continuous use. Regeneration of the membrane using NaOH 0.01 M eluent solution did not decrease significantly, ca. 10%, the membrane efficiency. The great advantage of these membranes is the low operational pressure required to obtain high phosphate retention.

Photocatalyst-coated self-cleaning ceramic tiles are in high demand for indoor and outdoor applications aimed at keeping a clean environment. Their industrial processing, however, often re-quires firing at temperature (1000–1200 °C)...

Composites of Keggin heteropolymetalates have been prepared and characterized by SEM, XPS, 31 P-magic angle spinning/nuclear magnetic resonance and differential scanning calorimetry. The phosphotungstic acid and phosphomolybdic acid form nanocomposites where the oxocluster structure is preserved and is highly dispersed over the material, probably inserted between the polymeric chains. Phosphovanadotungstic clusters suffer partial decomposition during composite formation, resulting in a biphasic microcomposite. The decomposition product, phosphotungstic acid presents surface segregation as shown by comparison of XPS and nuclear magnetic resonance results.