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Physical and Electrical Properties of Srtio3 and Srzro3

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Physical and Electrical Properties of Srtio3 and Srzro3 EPJ Web of Conferences 162, 01052 (2017) DOI: 10.1051/epjconf/201716201052 InCAPE2017 Physical and electrical properties of SrTiO3 and SrZrO3 Norhizatol Fashren Muhamad1, 2*, Rozana Aina Maulat Osman1, 2, Mohd Sobri Idris2, 3 and Mohd Najib Mohd Yasin1 1School of Microelectronic Engineering, Universiti Malaysia Perlis, Pauh Putra Campus, 02600 Arau, Perlis, Malaysia. 2CEO Frontier Material Research Centre, School of Material Engineering, Universiti Malaysia Perlis, 01000 Kangar, Perlis, Malaysia. 3School of Materials Engineering, Universiti Malaysia Perlis, jejawi, 02600 Arau, perlis, Malaysia. Abstract. Perovskite type oxide strontium titanate (SrTiO3) and strontium zirconate (SrZrO3) ceramic powder has been synthesized using conventional solid state reaction method. The powders were mixed and ground undergone calcinations at 1400oC for 12 h and sintered at 1550oC for 5h. X-ray Diffraction exposes physical properties SrTiO3 which exhibit cubic phase (space group: pm-3m) at room temperature meanwhile SrZrO3 has Orthorhombic phase (space group: pnma). The electrical properties such as dielectric constant (εr), dielectric loss (tan δ), and conductivity (σ) were studied in variation temperature and frequency. High dielectric constant of SrTiO3 and SrZrO3 were observed at 10 kHz for both samples about 240 and 21 respectively at room temperature. The dielectric loss of SrTiO3 and SrZrO3 is very low loss value approximately 0.00076 and 0.67512 indicates very good dielectric. 1 Introduction stability inside SrTiO3 are widely required for the application of high energy storage density dielectrics. Ceramic with perovskite crystal structure have long been Numerous attempts have been explored to further investigated due to their excellent ferroelectric, improve the properties of SrTiO3 based ceramics. paraelectric properties and chemically stable-structure. Among them, doping was considered as an effective Its applicable in displays, Multilayer Ceramic Capacitor approach for altering their properties. ZrO2 was selected (MLCC), electronic/piezoelectric devices, sensors, as cation substitute the B-type site of SrTiO3, because 4+ 4+ actuators, transducers, wireless communications [1-5]. Zr ions in SrTiO3 can stabilize the charge of Ti and The ideal Perovskite structure, which have the general suppress the oxygen dissociation when sintered at high formula ABX3 are consisting of two different cations (A temperature [13]. SrTiO3–SrZrO3 solid solution is one of and B) in equal ratio and an anion (X), which is usually them, which shows a super lattice structure due to its cell oxygen. enlargement as a result of tilting of BO6 (B = Ti, Zr) SrTiO3 and SrZrO3 are such materials that have octahedral [14]. This type of disorder perovskite solid been current interest to study due high dielectric constant solution offers exciting new possibilities both in the and its a lead free material. At room temperature, SrTiO3 investigation of fundamental physical behaviour and in has a simple cubic perovskite structure with space group the exploitation of novel properties for various (pm-3m) meanwhile SrZrO3 has orthorhombic structure applications. with space group (pnma) but both composition In this study, the electrical properties of SrTiO3 and undergoes a series of phase transitions by varying the SrZrO3 prepared via solid state reaction method were temperature. SrTiO3 undergoes phase transitions from investigated as respect to its physical structure high to low symmetry [6], while low to high symmetry properties. So, the system is expected to provide access for SrZrO3 [7]. to the desired phase or properties at convenient SrTiO3 and SrZrO3 is a perovskite dielectric temperatures. material applied to many application fields such as integrated microelectronic and microwave device [8]. These features are attributed by their unique properties 2 Experimental procedure such as high dielectric constant, low dielectric loss, tunability, high breakdown strength and low leakage The Perovskite-type oxide were prepared by mixing high current density [9-11]. Besides, the melting point of purity SrCO3 (99.9% Aldrich), TiO2 (99.0% Sigma o SrTiO3 and SrZrO3 is 2080 C and 2600°C respectively, Aldrich), and ZrO2 (99% Aldrich) in the appropriate making it applicable at high temperatures. In 2001, stoichiometric ratios. Sample was mixed and ground Shende et al. [11] claim that SrTiO3 and SrZrO3 can be using pestle and mortar with acetone as mixing medium. used in high-voltage applications because of its high The obtained powders were pressed into pellets of breakdown strengths which these materials are not diameter 13mm and heated at high temperature 1400oC expected to experience electromechanical failure for 12h with heating rate 5oC/m in the furnace. The mechanisms that may result in dielectric breakdown. samples were sintered for 1550oC for 5h in air followed Parida et al. [12] in 2012 report that SrTiO3 and SrZrO3 by characterization. has high permittivity and low loss make it suitable for X-ray Diffraction (XRD) were conducted at microwave antenna application. Based on Wang et al room temperature to determine the crystalline structure [13] study, high dielectric constant and favourable bias of all samples by using X-Ray Diffractometer (Model: D2 PHASER from Bruker AXS) in a 2θ range from 10o * Corresponding author: [email protected] © The Authors, published by EDP Sciences. This is an open access article distributed under the terms of the Creative Commons Attribution License 4.0 (http://creativecommons.org/licenses/by/4.0/). EPJ Web of Conferences 162, 01052 (2017) DOI: 10.1051/epjconf/201716201052 InCAPE2017 to 0o, using Cu Kα1 radiation. The electrical properties conductivity(σ) as well as impedance (Z) were studied such as dielectric constant (εr), dielectric loss (tan δ), by aking se of mpedance-capacitance-resistance 1(b). A th peaks sharp d er is no nwanted (LCR) meter Mod OKI 522-50 iTESTER) peak ound pattern, epresenting h crysta is mperatur 0-600oC. or is urpose, intered sing phas withou y mpurities nd en to e p wer coated with ilver aste trode. pdf reported SrTiO3=PDF00-035-0734] n [SrZrO3 Samples measured ver h frequency ang of 0 PDF01-076-9442]. om h diffraction attern, e – 100 with ifferen temperature. arameter along with th erag ys size for oth samples as een lculated shown n Table 1. iO3 was dexed ub phas (spac group: P -3 ) ith un ce with constan formulated 3 Results and Discussion by = 3.9000Å whic r in ntr to e orthorhomb structur of he rO with un l with Th structur f the oxid SrTiO3 and ZrO3 wer irst constant ormulated y 5.7915Å, 5.8129Å studied using owder -ray diffraction within 0° c=8.2000Å. to 80° value of 2θ in range as shown in Figure 1(a) and (a) SrZrO SrTiO3 (b) 3 (110) (200) (211) Intens u) (111) (220) (310) (402)(323)(204) (100) (111) (131) (210) (021) (300) 10 20 30 40 50 60 70 80 10 20 30 40 50 60 70 80 2Theta e) 2The gree) Fig. 1. Index X pattern f SrTiO3 (b rZrO3 Table 1 Latic arameter,crystallit i d p roup o SrTiO and rZrO3 SrTiO3 SrZrO3 a (Å) 3.900 (1) 5.7915 (1) b - 5.8129 (1) (Å) c (Å) - 8.2000 (1) V (Å3) 59.5 (1) 276.1 1) Crystallite Size 973.14 796.86 Space Group P - P Figure 3(a) and 3(b) shows the apacitance The Dielectric Constant (εr) was calculated against frequency, h spectrum isplace ward igher from h measured pacitance Cp) btain y CR meter etween 0 - 600oC mperatures. h variations of ielectr constan with mperatur at om selected frequency. iO3 exhibit pacitance f verage -9 - frequenc or SrTiO3 and rZrO3 ceram shown 10 0 meanwhile rO show o ve -10 - i Figure 2(a) and 2(b). r SrTiO3 ceram he capacitance alu in rang of 0 0 F, hus he dielectr constan decreases radually p certain rang of pacitance robably elonged grain temperatur and creases apidly with ncreasing boundary 16]. he high capacitance alu is btain o - temperature. Similar henomenon f h dielectric temperatur 00 C which ve 2.9x10 or SrTiO and - constan was bserved n ZrO3 ceram Ther is o 1.3x10 or SrZrO3 a kHz. Th capacitance elated cur peak etected for oth sample he whole to e ility f iO3 and rZrO3 sample llect nd measuremen mperatur range. Th dielectr onstant stor energy in h form f electr charge. of iO3 much igher mpared rO dielectr Figure 4(a) and 4(b) shows th dielectr ss constan is ecrease in from ɛr = (SrTiO3) to ɛr = (tan δ) of SrTiO3 and ZrO3. he dielectr ss for he o (SrZrO3) u to decreas in n polarization 15]. SrTiO3 measured below temperatur 200 shows very m ss which ou 0.001 t by increasi th temperatur from 00oC oC, dielectr loss 2 EPJ Web of Conferences 162, 01052 (2017) DOI: 10.1051/epjconf/201716201052 InCAPE2017 value fluctuate d increased abou . However, for ceram seems to emain similar end ut giv much o SrZrO3 below 00 C h dielectr loss is s an but higher f ss compared iO3 o increasing after 00 C. h dielectr loss f ZrO3 5000 5000 1 10 Hz 4500 4900 SrTiO3 (a) 4800 SrZrO (b) 4000 3 180 r 3500 r 160 3000 140 2500 120 2000 100 80 1500 60 Dielectr onstan 1000 Dielectr onstant, 40 500 20 0 0 50 100 150 200 250 300 350 400 450 500 550 600 50 100 150 200 250 300 350 400 450 500 550 600 Temperatu C) Temperetu C) Fig. 2. Temperatur ependen of ielectri nstant (εr) fo ) SrTiO3 (b) SrZrO3 -8 10 10-9 SrTiO (a) (b) 300 3 300 SrZrO3 350 350 400 400 450 450 500 500 550 550 600 -9 10 600 -10 10 Capacitance, F) -10 10 -11 10 3 4 5 3 4 5 10 10 10 10 10 10 Frequency ) Frequency z) Fig. 3.
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