.Z Aerosol Sci. Vol. 31, Suppl. I, pp. $909-$910, 2000 Pergamon www.elsevier.com/locate/j aerosci Poster Session II. Nanoparticles and nanomaterials TiO2 FILMS USING THE MOCVD METHOD AND TURBULENT FLOW U. BACKMAN, A. AUVINEN and J.JOKINIEMI VTT Energy, Aerosol Technology Group, P.O. Box 1401, FIN-02044 VTT, Finland. Keywords: Coating materials, Chemical Vapor Deposition, CVD, titanium dioxide INTRODUCTION Chemical vapor deposition of TiO2 at different conditions and substrate materials has been vastly studied. However, only a few studies are found on the deposition of TiO2 at atmospheric pressure (i.g. Collins 1994, Yang 1998). In this study TiO2 films were deposited on AISI 316L stainless steel using titanium tetraisopropoxide (TTIP) as precursor at atmospheric pressure with a turbulent gas flow. The aim of this work was to clarify how atmospheric pressure CVD functions with a turbulent gas flow. METHODS Nitrogen gas was bubbled through a flask containing the precursor held at 60°C or 80°C. The vapor was then transported through heated pipes to the tubular furnace acting as the reactor. A schematic figure of the experimental apparatus used is depicted in Fig. I. The dilution gas was pre-heated to 150°C to prevent condensation when let into contact with the TrIP saturated carrier gas. The flow rate of the carrier gas was 10 lpm and the total flow rate through the reactor was 100 lpm. One experiment with a total flow rate of 20 ipm was also carried out. Preheater , I Furnace Gas Wash Bottle Fume Hood [~>~] Control Valve DF<~ On/off Valve (~) Pressure Gouge D Critical Orifice Figure 1: Schematic figure of the apparatus used in these experiments. $909