The relative photoactivity of a series of nanophase ZnO powders with varying crystallite size (20-140nm) was determined using a chemical method based on the photobleaching behaviour of the stable radical 1,1-diphenyl-2-picrylhydrazyl (DPPH). It was confirmed that photoactivity behaviour increased (one to twofold) with decreasing crystallite size for crystallites <100nm. A further series of nanophase ZnO powders doped with metal ions showed that, depending on the type and/or level of dopant, the photoactivity behaviour of nanoparticles could be reduced by more than an order of magnitude.
Journal: TechConnect Briefs
Volume: 3, Technical Proceedings of the 2004 NSTI Nanotechnology Conference and Trade Show, Volume 3
Published: March 7, 2004
Pages: 370 - 374
Industry sector: Advanced Materials & Manufacturing
Topic: Nanoparticle Synthesis & Applications