ISSN:
1551-2916
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
This paper describes the preparation of homogeneous Bi7Ti4NbO21 single-phase ceramic powders of ∼55 nm crystallite size, at temperatures as low as 400°–500°C using a metal citrate complex method based on the Pechini-type reaction route. The thermal decomposition/oxidation of the polymerized resin, as investigated by TG/DTA, XRD, and SEM, led to the formation of a well-defined orthorhombic Bi7Ti4NbO21 compound with lattice parameters a= 0.544, b= 0.540, and c= 2.905 ± 0.0005 nm. Reaction takes place through an intermediate binary phase with a stoichiometry close to Bi20TiO32 which forms between 300° and 375°C. The metal-organic precursor synthesis method, where Bi, Ti, and Nb ions are first chelated to form metal complexes and then polymerized to give a gel, allows control of the Bi/Ti/Nb stoichiometric ratio leading to the rapid formation of nanosized bismuth titanate niobate (Bi7Ti4NbO21) ceramic powders, at temperatures much lower than usually needed by conventional processing of mixed-oxide powders.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1151-2916.2000.tb01325.x
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