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:
Thin fibrils (usually 20–100 nm in diameter) of ferroelectric PbZr0.52Ti0.48O3 have a preferred nucleation and growth in the [001] direction in small particles. X-ray diffraction with the X-ray beam facing the fibril surfaces, which lie along the [001] direction, thus involves reflections of manifested intensity from (100) and (010) planes. No reflection occurs from the perpendicular planes to the [001] fibrils. A transmission electron micrograph with the corresponding electron diffraction from fibrils confers the results of the preferred growth. The fibrils have a modified orthorhombic crystal structure of lattice parameters a=0.4038 nm, b=0.4017 nm, and c=04148 nm, with an enhanced 8.033 g/cm3 density over 8.006 g/cm3 in the usual tetragonal structure of a=0.4036 nm and c=04146 nm. Surface anisotropy in a fibril that imposes (and drives) a shear stress over growing crystallites (within the fibril) along the [001] surface favors this specific crystal structure in them according to the precursor structure. A single-phase sample is obtained in 2 h by heating of an amorphous template of precursor (of the metal cations with a polymer of polyvinyl alcohol and sucrose) at 500°–800°C in air.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1551-2916.2005.00638.x
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