Extended X-ray absorption fine structure, X-ray diffraction and Raman analysis of nickel-doped Ba(Mg1/3Ta2/3)O3

• Published in: Journal of the European Ceramic Society Vol. 27; no. 8-9; pp. 2995 - 2999
• Main Authors: MEI YU CHEN, CHANG, P. J, CHIA, C. T, LEE, Y. C, LIN, I. N, LIN, L.-J, LEE, J. F, LEE, H. Y, SHIMADA, T
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier 2007
• Subjects: Applied sciences; Building materials. Ceramics. Glasses; Ceramic industries; Chemical industry and chemicals; Electrotechnical and electronic ceramics; Exact sciences and technology; Technical ceramics; Extended X-ray absorption fine structure (EXAFS); Tantalum oxide; Electrical properties; Property composition relationship; Magnesium oxide; Dielectric properties; Doping; Barium Magnesium Tantalum Oxides Mixed; Experimental study; X ray diffraction; Oxide ceramics; EXAFS spectrometry; Barium oxide; Impurity effect; Nickel addition; Raman spectrum; Electroceramics
• ISSN: 0955-2219; 1873-619X
• DOI: 10.1016/j.jeurceramsoc.2006.11.025

Raman, XRD and EXAFS measurements of xBa(Ni1/3Ta2/3)O3 + (1-x)Ba(Mg1/3Ta2/3)O3 samples with x = 0-0.03 were performed to reveal the effect of nickel doping on the microwave properties. EXAFS showed that the nickel was located on the Mg lattice site. It was also found that, as the nickel concentration increased, the microwave dielectric constant decreased with the Ta-O and Ni-O bond distances. XRD showed that the 1:2 ordered structure was degraded with increasing of nickel concentration. The stretching phonon of the TaO6 octahedra, i.e. A1g(O) phonon near 800 cm-1, was strongly correlated to the microwave properties of xBa(Ni1/3Mg2/3)O3 + (1-x)Ba(Mg1/3Ta2/3)O3 samples. The large Raman shift and the large width of the A1g(O) implied rigid but distorted oxygen octahedral structure. Therefore, nickel doping lowered the dielectric constant and the Qxf value of the Ba(Mg1/3Ta2/3)O3 ceramic. 23 refs.