Phase, microstructure and microwave dielectric properties of Ca1−x La x Ti1−x/4O3 (x = 0–1) ceramics
La-doped CaTiO3 compounds with general formula Ca1−x La x Ti1−x/4O3 (x = 0–1) were prepared via a mixed oxide solid state sintering route. X-ray diffraction analysis revealed the formation of single phase compounds with orthorhombic (Pbnm) symmetry for x ≤ 0.25. At x ≥ 0.5, A n B n−1O3n type B-site deficient hexagonal perovskite phases formed along with minor secondary phases. The grain size and morphology and hence, the microwave dielectric properties varied substantially with change in dopant concentration (x). The optimum microwave dielectric properties (εr = 45.3, Q × f o = 20506 GHz and τf = −14.8 ppm/°C) were achieved at x = 0.75.
KeywordsMicrowave Dielectric Property Dielectric Resonator Increase Sinter Temperature Optimum Sinter Temperature Electron Scanning Electron Microscope
The authors acknowledge the financial support of the Higher Education Commission of Pakistan under the IRSIP program and Prof. I. M. Reaney electro-ceramics group for facilitating the authors at the Electro-ceramics laboratory, Department of Material Science and Engineering, University of Sheffield (UK). The financial support extended to Materials Research Laboratory by the Khyber Pakhtunkhwa Government through the Directorate of S&T, Peshawar is highly acknowledged.
- 4.R. Muhammad, Y. Iqbal, C. Rambo, J. Mater. Sci. Mater. Electron. doi: 10.1007/s10854-014-2630-7
- 6.M. Saleem, Y. Iqbal, S. Qin, X. Wu, R. Muhammad, F. Zhu, J. Mater. Sci. Mater. Electron. doi: 10.1007/s10854-014-2568-9
- 14.R. Muhammad, Y. Iqbal, C. Rambo, J. Mater. Sci. Mater. Electron. doi: 10.1007/s10854-014-2662-z