Contents lists available at ScienceDirect Ceramics International journal homepage: www.elsevier.com/locate/ceramint Enhanced functional response of high temperature stabilized (1-x)PMN- xPT ceramics Pius Augustine a,b, ⁎ , Martando Rath a , M.S. Ramachandra Rao a,⁎⁎ a Department of Physics, Nano Functional Material Technology Centre and Material Science Research Centre, Indian Institute of Technology Madras, Chennai 600036, India b Department of Physics, Sacred Heart College (Autonomous), Kochi 682013, India ARTICLE INFO Keywords: A. Powders: solid state reaction B. Grain size C. Electrical properties D. Perovskites E. Capacitors ABSTRACT Synthesis of single phase (1-x)Pb(Mg 1/3 Nb 2/3 )O 3 -xPbTiO 3 ceramics with enhanced electrical response was achieved by excluding excess PbO from the precursor, making them suitable for device applications. This report is an inquiry into the effect of high temperature stabilization used for the realization of single phase PMN-PT ceramics on the electrical properties exhibited by the compositions in the morphotropic phase boundary. Functional response exhibited by the high temperature stabilized ceramics is correlated with the structural fluctuations in the morphotropic phase boundary and the grain pattern observed in the microstructure. Gradual transition from diffuse relaxor ferroelectric system to normal ferroelectric system was also studied. Enhanced ferroelectric response of the composition x=0.35 (P sat =32.03 μC/cm 2 ,P r =25.11 μC/cm 2 ,E C =6.04 kV/cm, R sq =1.28, Absolute area=3768, range of electric field=-37 to +37 kV/cm and recoverable energy density= 59.86 mJ/cm 3 ), the improved dielectric behavior of the composition x=0.325 (ε r(max) =15,703, Tanδ max =0.02 and γ=1.79 (at 1 kHz)) and the high piezoelectric coefficient d 33 (390 pC/N and 365 pC/N for x=0.325 and x=0.35 respectively), obtained in the study have confirmed the device worthiness of the synthesized ceramic compositions. This study was carried out to establish that, modulated high temperature synthesis will not deteriorate the electrical properties of the lead based system like PMN-PT, rather will assist the completion of perovskite phase formation, and thus enhance the functional response of the ceramic. 1. Introduction The characteristic phenomenological definition of the relaxor ferro- electric derives from its temperature dependent diffuse phase transi- tion behavior and relaxors exhibit anomaly in the proximity of ferro- electric/paraelectric phase transition with improved electrical response [1,2]. Pure PMN (x=0) is a cubic relaxor material with transition temperature (T C )~ - 10 °C, whereas PT (PbTiO 3 ) is a normal ferro- electric with tetragonal symmetry and T C ~490 °C [3]. The addition of lead titanate (PT) causes shift in the B-site group of cations and O 2- ions relative to Pb 2+ ions, which in turn induces non-centrosymmetry in PMN-PT system, resulting in excellent relaxor and ferroelectric properties [4,5]. While pure PMN and (1-x)PMN-xPT with ׳x ׳below 13% exhibit incipient ferroelectric nature with cubic symmetry, the remaining compositions display appreciable ferroelectric response. If the PT content in the solid solution of (1-x)PMN-(x)PT is greater than 40%, it behaves like normal ferroelectric [6]. Among the different compositions, a narrow window with ׳x ׳in the range of 0.31–0.37, called morphotropic phase boundary (MPB), has excellent electrical, optical and electromechanical characteristics making PMN-PT a smart material. Although the response of an ensemble of polar nano regions (PNR) to external stimuli partially explains the behavior of mesoscopic ordered PMN-PT like relaxor material, a unique theory comprehen- sively illustrating the properties of relaxor material is lacking, despite extensive studies [7,8]. The super-paraelectric model, with the rotation of the resultant electric polarization, or the dipolar glass model with random field, was proposed to describe the behavior of PMN-PT ceramic with a greater degree of accuracy [8]. PMN-PT system is expected to show gradual increase in hysteresis and decrease in strain along the MPB due to the structural change from pseudocubic to tetragonal crystal symmetry [9]. Further, addition of lead titanate (PT) causes substitution of Ti 4+ ion for complex B-site (Mg 1/3 Nb 2/3 ) 4+ ion, which reduces the ferroelectric ordering in PMN, and in turn impairs the relaxor character with temperature and dielectric dispersion with http://dx.doi.org/10.1016/j.ceramint.2017.04.111 Received 23 December 2016; Received in revised form 28 March 2017; Accepted 19 April 2017 ⁎ Corresponding author at: Department of Physics, Nano Functional Material Technology Centre and Material Science Research Centre, Indian Institute of Technology Madras, Chennai 600036, India. ⁎⁎ Corresponding author. E-mail addresses: piustine@gmail.com (P. Augustine), msrrao@iitm.ac.in (M.S. Ramachandra Rao). Ceramics International xxx (xxxx) xxx–xxx 0272-8842/ © 2017 Elsevier Ltd and Techna Group S.r.l. All rights reserved. Please cite this article as: Augustine, P., Ceramics International (2017), http://dx.doi.org/10.1016/j.ceramint.2017.04.111