From Hybrid Films to Mesoorganized Multi-metal-oxide Nanocrystalline Films(M_3NF),preparation and characterization.

摘要

High quality and reproducible thin silica and non-silica mesoporous films were obtained with mono-oriented organised mesoporosity,fitting various symmetry groups(i.e.p6m,Pm3n,Im3m,...).The Evaporation Induced Self Assembly(EISA)mechanism of structuration was studied through in-situ time-resolved SAXS,interferometry and spectroscopic ellipsometry investigations during dip-coating.A Modulable Steady State(MSS)was found during which the system is in quasi-equilibrium with its environment and during which the final structure is formed.The corresponding Self-Assembly mechanism was found to be governed by a competition between evaporation,micellization and condensation that depend on various critical chemical and processing parameters the influence of which have been summarized into directly usable phase diagrams.Calcined SiO_2 and TiO_2 mesoporous films structure(pore size and anisotropy,porous volume and surface)and mechanical properties(young modulus)were investigated by UV-Visible spectroscopic ellipsometry.Finally,thanks to a specially designed block copolymer,one further step was accomplished by achieving the dip coating and controlled nano-crystallisation of various metallic and multi-metal-oxides films(M3NF)of composition Co_xTi_((1-X))O_((2-X))with ilmenite or doped Anatase structure,and SrTiO_3 and MgTa_2O_6 with perovskite structure.Attending the well known magnetic,dielectric and catalytic properties of these structures,M3NF are highly compatible with high technology applications in microelectronic,energy transfer devices,spintronic,nano-mechanical adjustments,data storage,oxide fuel cells ...