Synthesis of titania-silica composite nanoparticles in the case of combined injection of their precursor vapors into flow type plasmachemical reactor

Abstract

The numerical simulation of one-stage synthesis of ‘titania core-silica shell’ composite nanoparticles in the working zone of the plasmachemical reactor has been performed using the chloride method. In these calculations it is implied the joint oxidation of premixed vapors of silicon and titanium tetrachlorides. The computations have been carried out based on the model devised for the case of the separate oxidation of the above mentioned precursors. The present model accounts for the scenario of formation of the silica shell that covers the titania core incompletely. Based on the modified model the information regarding the core size of composite particles, the thickness of their shell as well as concentrations of titania particles with and without silica shell has been extracted. The flow rates and the mass fractions of the premixed precursors in gas mixture injected as side jets into the working zone of the reactor were chosen as those for experiments. The numerical results in the cases of separate and joint oxidation of vapors of silicon and titanium tetrachlorides have been compared.