Effect of 2-propenyltrimethylsilane and magnetic field effect on photochemical Fe/Co fine particle formation from a ternary gaseous mixture

From a gaseous mixture of iron pentacarbonyl (Fe(CO)5), cobalt tricarbonyl nitrosyl (Co(CO)3NO), and 2-propenyltrimethylsilane (allyltrimethylsilane) (ATMeSi), spherical aerosol particles with a mean diameter of 0.36 μm were produced under UV light irradiation. Addition of ATMeSi accelerated the chemical reactions of Co(CO)3NO to produce aerosol particles efficiently, and decelerated those of Fe(CO)5 to inhibit the formation of crystalline deposits which were mainly composed of Fe2(CO)9 structure involving Fe–C(O)–Co bond. Chemical structure and chemical compositions of the sedimentary aerosol particles were investigated from FT-IR and SEM–EDS analyses. Co species were rich in the sedimentary particles, and efficient excitation of Co(CO)3NO molecules at 355 nm with a Nd:YAG laser resulted in a greater abundance of Co species. Under a magnetic field of up to 5 T, sedimentary aerosol particles were synthesized from the ternary gaseous mixture. Chemical composition of the particles was dependent on magnetic field strength, and atomic ratios of Fe and Si to Co atom increased above 3 T. Magnetic field effect on the nucleation reactions was discussed briefly.