Journal of Materials Science

, Volume 50, Issue 9, pp 3510–3516 | Cite as

Structure and microwave dielectric properties of La5−x Sr x Ti4+x Ga1−x O17 ceramics

  • Raz Muhammad
  • Yaseen Iqbal
  • Ian M. Reaney
Original Paper


Single phase polycrystalline ceramics in the La5−x Sr x Ti4+x Ga1−x O17 (x = 0–1) system with A5B5O17 type layered perovskite structure were prepared via a mixed-oxide, solid state sintering route. X-ray diffraction revealed orthorhombic, Pnnm symmetry with Raman spectra consistent with this space group. The sintered ceramics exhibited a plate-like grain structure with a relative density, 94–97.5 %. The end member, La5Ti4GaO17 had ε r = 42.31, Q × f o = 17,093 GHz, τ f = −34.53 but τ f could be tuned close to zero by Sr and Ti substitution at the A- and B-sites, respectively. An optimum composition La4.5Sr0.5Ti4.5Ga0.5O17 was achieved at x = 0.5 with ε r = 51, Q × f o = 15,290 GHz and τ f = −2.2 ppm/oC.


Relative Permittivity Ga2O3 Microwave Dielectric Property Dielectric Resonator Small Ionic Radius 
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The authors acknowledge the financial support of the Higher Education Commission of Pakistan under the IRSIP program. The financial support extended by the Khyber Pakhtunkhwa Government through the Directorate of S&T, Peshawar for the upgradation of Materials Research Laboratory, University of Peshawar is highly acknowledged.


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.Materials Research Laboratory, Department of PhysicsUniversity of PeshawarPeshawarPakistan
  2. 2.Department of Materials Science and EngineeringUniversity of SheffieldSheffieldUK

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