Metal Monoxide Diagnostics in Particle Synthesis Flames

Recent measurements of metal monoxides in powder producing flames are reviewed and discussed. While the mole fraction profiles of species such as SiO, AlO, and TiO can in principle be used to infer useful information about metalorganic decomposition in flames, the dominant features of these profiles appear to be due to the partial pressure of the solid product. Most monoxides do serve as good markers of the flame zone, but are no better than emission profiles of key excited intermediates. Monoxide profiles may, however, be of significant value in validating future comprehensive multiphase models of the synthesis process.