Controlling the Photoactivity of Nanoparticles
P. Casey, S. Boskovic, K. Lawrence and T. Turney
Keywords: nanoparticles, photoactivity, doped, zinc oxide
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.
Nanotech 2004 Conference Technical Program Abstract