Cobalt Ferrite Nanoparticles from Single and Multi‐Component Precursor Systems

Abstract

Highly crystalline CoFe 2 O 4 nanoparticles (ϽdϾ ϳ 5.6 nm) were synthesized by thermal decomposition of (i) single molecular precursor CoFe 2 (O t Bu) 8 and (ii) stoichiometric mixture of individual metal precursors. The precursors were thermolyzed in a highboiling solvent (Docosane, bp. 369°C) to produce uniformly dispersed cobalt ferrite nanoparticles in the case of molecular pre-

All‐alkoxide based deposition and properties of a multilayer La0.67Sr0.33MnO3/CoFe2O4/La0.67Sr0.33MnO3 film

“…The single-source CoFe 2 (O t Bu) 8 precursor, was obtained from the laboratory of Prof. Sanjay Mathur, University of Cologne, Germany, as a sublimed powder. [24] An analogous structure is shown in Figure 2. The CoFe 2 (O t Bu) 8 powder was dissolved in toluene : moeH to yield a solution with a total metal concentration of 0.33 M. This solution was filtered through a 20 nm Anotop alumina membrane (from Whatman) to remove suspended particles and get a clear dark coloured solution.…”

“…CFO : A single‐source molecular precursor, CoFe 2 (O t Bu) 8 was previously developed for CVD synthesis and thermal decomposition into nanoparticles of CoFe 2 O 4 at low temperatures [24] . An analogous alkoxide is shown in Figure 2.…”

“…0.5 M (metal) solution with the composition La : Sr:Mn (2 : 1 : 3). The single‐source CoFe 2 (O t Bu) 8 precursor, was obtained from the laboratory of Prof. Sanjay Mathur, University of Cologne, Germany, as a sublimed powder [24] . An analogous structure is shown in Figure 2.…”

Molecular Level Synthesis of InFeO3 and InFeO3/Fe2O3 Nanocomposites

“…Heterometallic alkoxides are intrinsically efficient precursors to mixed-metal oxides due to preformed heterometallic bridges connected through the alkoxide oxygen (−M–(O)­R–M′−) which generally allows their conversion to desired oxide ceramics without lengthy heat treatments since the formation of solid-state phases is not only driven by Fickian diffusion. The selective conversion of a large number of metal alkoxides to ternary ceramics and composites has been demonstrated to verify the role precursor chemistry plays in the synthesis of phase pure material. ,,− ,,− ,− The formation of nanoscaled composites from molecular sources allows to tailor the material properties not possible by conventional synthesis methods, which generally lead to elemental segregation and phase separation. The sol–gel processing and gas phase depositions of monometallic metal alkoxides as single-source precursors are comprehensively studied; however, mixed-metal compositions are relatively less investigated. ,− ,,,,− Despite the potential advantages of chemical processing, the major constraint in the application of heterometallic alkoxides is related to their limited synthetic access and dearth of structural data on metal alkoxide frameworks.…”

Monomeric Iron Heteroarylalkenolates: Structural Design Concepts and Investigations on Their Application in Chemical Vapor Deposition

“…The production of phase selective and homogeneous metal oxide materials requires precursors that ensure specific and well-defined properties, such as oxidation state, volatility, and stability against air and moisture, essential for routine handling as starting materials. − A judicious balance between chemical reactivity and kinetic stability is often achieved by the interplay of steric and electronic factors . Nevertheless, there exist only few examples of successful precursor design as the incorporation of larger ligands adversely influences the vapor pressure due to the increase of the molecular weight .…”