کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1653519 | 1007664 | 2007 | 5 صفحه PDF | دانلود رایگان |
Preparation of BaTiO3 nanopowders (37–42 nm) is carried out by a controlled reconstructive thermal decomposition and crystallization from an amorphous polymeric precursor with polyvinyl alcohol (PVA) and sucrose at 400–600 °C in air. The Rietveld refinement of the XRD profile, processed at 600 °C in 2 h, infers the P4mm tetragonal crystal structure (95% of tetragonality) of the as prepared BaTiO3 nanopowders, with a = 0.3994 nm and c = 0.4024 nm. A cubic symmetry (Pm3m) of 5% in amount with a = 4.0057 is also detected in addition with tetragonal symmetry. The characteristic tetragonal splitting of 002/200 XRD peaks also supports the tetragonal symmetry (c / a = 1.0075) of the as prepared BaTiO3 nanopowders. The average particle size (D) of the BaTiO3 powders, estimated with the help of the specific surface area, measured by BET method, is 39.91 nm. Average D value, calculated by Δ2θ1 / 2 in the XRD peaks with the Debye Scherrer relation is ∼ 40 nm. TEM study measures the particle size of the BaTiO3 powders with an average diameter of 37 to 42 nm.
Journal: Materials Letters - Volume 61, Issue 3, February 2007, Pages 850–854