title: On the mechanism of nanoparticle formation in a flame doped by iron pentacarbonyl.
abstract: In this work we have investigated the mechanism of nanoparticle synthesis in a low pressure, premixed, laminar flat flame of CH4-O2, doped with iron pentacarbonyl using a combined quartz-crystal-microbalance-particle-mass-spectrometry apparatus. We have unambiguously demonstrated that the formation of nanoparticles in iron pentacarbonyl-doped flames occurs very early, in close proximity to the burner surface, prior to the flame front. This early rise of nanoparticle mass concentration is followed by a sharp drop in nanoparticle concentration at the high temperature flame front. This "prompt" nanoparticle generation is consistent with kinetic models describing iron cluster formation. The observation of this phenomenon in a quasi-one-dimensional premixed flat flame strengthens our previous findings and points out that the "prompt" nanoparticle formation is a general phenomenon, not limited to diffusion flames. It presents a challenge and a trigger for further development of the existing mechanisms for gas phase synthesis of iron oxide particles in flames.
authors.affiliation: School of Chemistry, Tel Aviv University, Tel Aviv 69978, Israel.
authors.forename: Marina
authors.initials: M
authors.lastname: Poliak
authors.forename: Alexey
authors.initials: A
authors.lastname: Fomin
authors.forename: Vladimir
authors.initials: V
authors.lastname: Tsionsky
authors.forename: Sergey
authors.initials: S
authors.lastname: Cheskis
authors.forename: Irenaeus
authors.initials: I
authors.lastname: Wlokas
authors.forename: Igor
authors.initials: I
authors.lastname: Rahinov
mesh_terms: D004867:Equipment Design; D006358:Hot Temperature; D058085:Iron Compounds / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000295:instrumentation; D010316:Particle Size; D011312:Pressure; D058525:Quartz Crystal Microbalance Techniques
chemical_list: D058085:Iron Compounds; C515100:iron pentacarbonyl