Titanium doped tin dioxide as potential UV filter with low photocatalytic activity for sunscreen products
Titanium doped tin dioxide nanopowders were produced using a simple precipitation method and displayed the same crystalline structure and decreasing particle size with increasing dopant concentration. Optical absorption studies showed broad absorption in the UV region for each sample and enhanced absorption relative to commercial zinc oxide (ZnO) but significantly less absorption than the uncoated commercial titanium dioxide nanopowder (P-25). Photocatalytic studies showed that the 5%Ti doped sample had the lowest methylene blue (MB) degradation rate of (1.9±0.4)x10-3 min-1, followed by the undoped ((2.6±0.4)x10-3 min-1) and 10% Ti-doped ((4.5±0.4)x10-3 min-1) samples. All of the nanoparticle samples demonstrated substantially lowered photocatalytic activity compared to commercial ZnO and P-25 reference particles.