Structural and dielectric properties of phosphorous-doped PLZT ceramics

PUJA GOEL¹, SUBHASH SHARMA¹, KANHAIYA LAL YADAV^1,*

and AJIT RAM JAMES²

¹Smart Materials Research Laboratory, Department of Physics, Indian Institute

of Technology, Roorkee 247 667, India

²Defence Metallurgical Research Laboratory, Kanchanbagh,

Hyderabad 500 058, India

^*Corresponding Author: E-mail: klyadav35@yahoo.com

Abstract. In the present work we have reported the unique effects

of P$_{2}$O$_{5}$-doped PLZT ceramics with composition

(Pb$_{0.92}$La$_{0.08})$(Zr$_{0.65}$Ti$_{0.35})$O$_{3}$ + $x$ wt{\%}

of P$_{2}$O$_{5}$ (where $x =1$, 3 and 5) prepared chemically by

co-precipitation method. X-ray diffraction studies suggest that the

prepared compound was very fine (10--25 nm), homogeneous and of

rhombohedral symmetry. The apparent density of samples decreased

with the P$^{5+}$ additions. Studies of dielectric constant and

dielectric loss as a function of frequency (10--1000 kHz) and

temperature suggest that the compound undergoes diffuse type of

phase transition without any sign of relaxor behaviour. With

increasing $x$, dielectric constant was found to decrease appreciably,

whereas Curie temperature ($T_{\rm C}$) was found to increase.

Keywords. Ceramics; X-ray diffraction; pyrochlore phase; PLZT; dielectric properties.

PACS Nos 77.84.Dy; 77.84.-s; 77.80.-e; 70