Molecular precursor approach to nano-scaled ceramics and metal/metal oxide composites

Heterometal alkoxides are rued as single-source precursors to obtain nano-scaled thin layers and powders of a variety of oxide ceramics and composites. The hydride alkoxide [Mg{H2Al(OBut)(2)}(2)] has been used for low-temperature deposits of crystalline MgAl2O4 spinel. The mixed-metal alkoxide [BaZr(OPri)(5)(OH) ((PrOH)-O-i)(3)](2), based on 1:1 stoichiometry of the metals, has been used for clean and selective synthesis (sol-gel) of nanocrystalline BaZrO3 ceramic. Using heterometal alkoxide [Ni2Sn2(OBut)(8)] in a CVD process gave a binary intermetallic compound (Ni3Sn4) in an oxide matrix (SnO2) The composite system Ni/Al2O3 obtained on reducing NiO with [H2Al(OBut)](2) shows remarkably high catalytic activity in hydrogenation of C-C double bonds. Thin layers of a composite containing nano-sized Ni/Al2O3 have been deposited using [Ni{Al(OPri)(4)}(2)] in a CVD process. (C) 1999 Acta Metallurgica Inc.