J. Marc Whalen, Curtis R. Fekety, Andrey Filippov, Damon C. Osterhout, Shang-Cong Cheng, and Carlton M. Truesdale. Sullivan Park Research Center, Corning Inc., Corning, NY 14831
Flame spray pyrolysis (FSP)is a versatile method for generating multicomponent nanoparticles. Typically, a flammable solution is prepared with the desired ratio of cationic components, atomized and combusted to form nanoparticles of the same cationic composition. High degree of control over the particle deposition, relatively cold targets and high deposition rates are the features difficult to achieve simultaneously with commonly used thermophoretic (flame) deposition. This paper describes a high rate process for nanopowder generation and electrostatic deposition of the particles onto glass substrates using a two-stage charging-collection system. In the FSP system used, flammable alkoxide based solutions were pumped to an external mixing gas-assisted atomizer by a precision piston pump. The resulting spray formed a self sustaining flame when passed through a ring of twelve CH4/O2 pilot flames. The flow carrying nanoparticles produced in the FSP unit passed through corona discharge section (a set of corona brushes and the opposite sign planar electrode) slightly above the flame for ionic elec-trostatic charging. After that, the carrier gas with parti-cles cooled down in the vertical part of the generator. As examples, generation of several commercially relevant materials of very different composition, including crys-talline titania (TiO2) and a glass from the MgO-Al2O3-SiO2 system (cordierite) is discussed.