Synthesis of non-agglomerated nanoparticles by an electrospray assisted chemical vapor deposition (ES-CVD) method

• Published in: Journal of aerosol science 2003-07, Vol.34 (7), p.869-881
• Main Authors: Nakaso, K., Han, B., Ahn, K.H., Choi, M., Okuyama, K.
• Format: Article
• Language: English
• Subjects: Chemical vapor deposition (CVD); Chemistry; Colloidal state and disperse state; Electrospray; Exact sciences and technology; General and physical chemistry; Nanoparticle; Non-agglomerated particles; Particle charging; Physical and chemical studies. Granulometry. Electrokinetic phenomena
• ISSN: 0021-8502; 1879-1964
• DOI: 10.1016/S0021-8502(03)00053-3

Non-agglomerated spherical silicon, titanium and zirconium oxide nanoparticles were prepared using an electrospray assisted chemical vapor deposition (ES-CVD) process. Metal alkoxides in conjunction with an electrospray method were used to introduce charged precursors into a CVD reactor. The ions are produced during evaporation of the charged droplets, and they probably act as seed nuclei (i.e., ion-induced nucleation) and/or, they are attached to the produced particles. The experimental results were compared with those obtained using a conventional evaporation CVD method. The particles generated using the conventional evaporation method were agglomerated to a considerable extent irregardless of the type of particle. Whereas, at the same conditions, high concentrations of non-agglomerated nanoparticles having diameters in the range of 10– 40 nm were obtained using the ES-CVD method. This appears to be due to the charging effects of the generated particles, that is, the electrostatic dispersion of unipolarly charged particles. The size of the non-agglomerated particles in the ES-CVD method was reduced as the results of the decease in the concentration of precursors introduced by electrospray.