Upon characterization the morphology of CAO sample by electron
microscopy (Fig. 3(a) and (b)), the morphology characterized
by TEM was distinctly similar to that by SEM. The CAO sample was
composed of quite distorted plates with 200e350 nm thick. The
present morphology of CAO sample is quite different from that
synthesized by microwave processing (irregular particles with
unclear facets) [13] and conventional heating method: ~1 mmgrains
[2] and loose agglomerates of ~200 nmgrains [5]. The SAED pattern
(Fig. 3(c)) was recorded on the CAO crystalline plate of Fig. 3(b).