The work presented here consists of two parts: The first focuses on the development of a novel Rapid Freeze-Out synthesis method for the fabrication of magnetic nanophases of Fe, Co, Ni and assorted binary systems. The second part concerns the synthesis and doping of alkaline earth sulfides with rare earth elements to enhance their luminescence properties for cathode ray tube phosphorescent material.; Rapid Freeze-Out versatile synthetical method was developed using high melting arenes to trap and control nanoparticle formation in statu nascendi of Fe, Co and Ni by matrix solidification from carbonyl precursors. The solid matrix was found to protect the particles from oxidation allowing long-term storage of these highly reactive materials. Nanoparticle formation in the 2--18 nm (Fe), 5--26 nm (Co) and 35--50 nm (Ni) range were confirmed by TEM micrographs. The Fe, Co and Ni phases exhibit superparamagnetism determined via SQUID measurements. XPS and XRD data indicate unusual electronic deshielding of the surface atoms. The developed synthesis approach has the potential for industrial scale-up and continuous manufacturing of nanoparticle materials in a wide range of compositions and stoichiometries demonstrated by fabrication of a variety (12) of binary nanophases using separate and single source precursors. Nanoparticle formation in the 6--26 nm range was confirmed for the FeCd phase. Very interesting results were obtained for the CoBi system with nanoparticles exhibiting the high pressure cubic Bi phase in the particle core with a rhombohedral shell. Other unusual phases were obtained with FeCu and FeCd. The developed synthesis allows access to intermetallic nanophases of immiscible metal combinations not possible in form of bulk alloys. It was shown that with the proper reaction design unusual nanophases are accessible, such as certain size clusters of one element surrounded by a nanophase matrix of another element as well as the fabrication of phases consisting of small particles of one composition coated with a layer of another material, promising the development of new materials with unusual properties.; In part two, chalcogenide metathesis reactions were studied. Metathesis reactions were used to synthesize CaS, SrS and their Eu-doped derivatives as well as HgCdTe (MCT) semiconductor nanophases. Phosphor materials such as SrS and CaS are of great interest because of their applications for use as cathode ray tube phosphorescent material due to their luminescent properties. A study of metathesis reaction to the formation of CaS and the Eu2+ doping of CaS for luminescence was preformed. Lastly, metathesis reactions to the formation of MCT nanoparticles and bulk powders were studied. MCT is of great interest because it allows the careful tuning of band gap. This can be used for applications in electronics such as solar cells and photoluminescence.
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