Suh, Won Hyuk Suslick, Kenneth S. Magnetic and Porous Nanospheres from Ultrasonic Spray Pyrolysis We have used an inexpensive high-frequency ultrasound generator from a household humidifier to create a useful source for ultrasonic spray pyrolysis and produced submicrometer silica particles that are porous on the nanometer scale. By using two heated zones, we first initiate polymerization of organic monomers in the presence of silica colloid, which creates <i>in situ</i> a composite of silica with an organic polymer, followed by a second heating to pyrolyze and remove the polymer. The morphology and surface area of the final porous silica are controlled by varying the silica-to-organic monomer ratio. In a single flow process, ferromagnetic cobalt nanoparticles can be easily encapsulated in the porous silica, and the resulting nanospheres are extremely resistant to air oxidation. Products were characterized by SEM, (S)TEM, EDS, XPS, and SQUID. submicrometer silica particles;flow process;surface area;spray pyrolysis;Porous Nanospheres;monomer;silica colloid;SEM;Ultrasonic Spray Pyrolysis;ultrasound generator;air oxidation;household humidifier;nanometer scale;XPS;polymer;EDS;cobalt nanoparticles 2005-08-31
    https://acs.figshare.com/articles/journal_contribution/Magnetic_and_Porous_Nanospheres_from_Ultrasonic_Spray_Pyrolysis/3270610
10.1021/ja050693p.s001