Wet chemical synthesis of surface passivated metal nanoparticles via decomposition of organometallic complexes

• Applicant: Professor Dr. Roland A. Fischer
• Subject Area: Inorganic Molecular Chemistry - Synthesis and Characterisation ; Physical Chemistry of Solids and Surfaces, Material Characterisation
• Term: from 2009 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 119070151

The primary objective of this proposal is the investigation of non aqueous organometallic synthesis of bimetallic alloy nanoparticles M1-xEx, where one component is a ferromagnetic transition metal M (Fe, Co, Ni), and the other is an oxophilic metal E (Al, Si, Zn). These materials can be accessed by cohydrogenolysis of two suitable molecular precursor complexes bearing hydrocarbon or amide ligands. One associated task is the dispersion of the nanoalloys as colloids in solution and basic studies on the variation of the particle size and shape by changing the reaction conditions (e.g. addition of surfactants). The second important aspect of this work will be the investigation of the oxidation behavior of the synthesized M1-xEx nanoparticles, i.e. the selective oxidation of the oxophilic metal E, respectively, which results in core-shell particles of the type M1-xEx-d@(EOn)d. Upon phase segregation, the core is enriched with the metal M, which is protected from further corrosion by an oxide shell of the oxophilic element E. Since small nano particles of ferromagnetic metals are prone to oxidation, which leads to a drastic decrease of their magnetic properties, the passivation of ferromagnetic metal nanoparticles is of high interest in material science. Hence, coated metal nanoparticles should exhibit a long term resistance versus corrosion, which would make them promising candidates in applications, e.g. data storage etc.

• DFG Programme: Research Grants
• International Connection: France
• Participating Person: Dr. Bruno Chaudret