The effects of process parameters on iron nanoparticle formation and properties while using ferrocene as a precursor in a low-pressure capacitively coupled plasma are investigated. The L18 array of the Taguchi method, followed by the L4 array, is used with the notional objective of increasing the yield of nanoparticles. A study of the size, shape and composition of the particles (using transmission electron microscopy, high-resolution transmission electron microscopy, Raman spectroscopy, x-ray diffraction, CHON and inductively coupled plasma-atomic emission spectroscopy analysis) gives an insight into the role played by various process parameters. Pressure is the most critical parameter in increasing nanoparticle yield, whereas hydrogen flow plays a key role in determining the nanoparticle size and composition. Atomic hydrogen helps in removing amorphous carbon and reducing the nanoparticle size. RF power plays an important role in the dissociation of ferrocene thus also affecting the composition. Nanoparticles obtained using optimized conditions are a mixture of Fe3O4 and Fe2O3 with cluster size 25–40 nm in diameter that are further made up of 2–4 nm crystallites. Magnetic property measurements indicate that the nanoparticles are super-paramagnetic in nature.
Iron oxide nanoparticles are synthesized using organometallic precursors namely, iron (III) acetylacetonate and cyclopentadienyliron dicarbonyl dimer in a capacitively coupled low pressure plasma system. They are characterized using High Resolution Transmission Electron Microscopy (HRTEM), X-ray Di®raction (XRD), magnetization studies and Raman spectroscopy. The role of hydrogen and RF (Radio Frequency) power on the crystalline and magnetic properties of the nanoparticles is studied. Incorporation of hydrogen to the Plasma-Enhanced Chemical Vapor Deposition (PECVD) chamber during the synthesis facilitates both crystallization of iron oxide nanoparticles and reduction of carbon content in the product. The saturation magnetization of iron oxide nanoparticles synthesized using iron (III) acetylacetonate and cyclopentadienyliron dicarbonyl dimer in presence of hydrogen at 200 W RF power is higher than that synthesized in the absence of hydrogen at 50 W RF power. In case of nanoparticles Int. J. Nanosci. Downloaded from www.worldscientific.com by NORTHWESTERN UNIVERSITY on 03/25/15. For personal use only.synthesized using iron (III) acetylacetonate, the saturation magnetization increases from 1.5 emu g À1 to 19 emu g À1 , and for the same synthesized from cyclopentadienyliron dicarbonyl dimer it increases from from 3.2 emu g À1 to 22.4 emu g À1 .
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.