Local Structure Analysis of KNbO₃ Nanocrystals with Cubic Shape

抄録

KNbO₃ nanocrystals were grown by solvothermal technique assisted by a microwave treatment. The morphology of nanocrystals is a cubic shape and the crystal structure is also cubic system. This is an ideal case for the so-called Sherrer's equation. We performed high- energy X-ray scattering to extract various structural parameters. The particle size can be evaluated by the Sherrer's equation. The unit cell size of the KNbO₃ nanocrystals was reduced as the particle size increased. The local structure of the nanocrystals was found to be a rhombohedral structure similar to that of the bulk KNbO₃. Although the periodic structure of the perovskite system unchanged locally, the first-nearest neighbor and the second-nearest neighbor bond distances corresponding to Nb-O and K-O was changed as the particle size increased.