Large Electrostrain from Ferroelectric Aging Effect around

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Large Electrostrain from Ferroelectric Aging Effect around Morphotropic Phase Boundary Yang Yang, Zhijian Zhou, Lipeng Xin, Chao Zhou, Lixue Zhang, Andong Xiao, and Xiaobing Ren J. Phys. Chem. C, Just Accepted Manuscript • DOI: 10.1021/acs.jpcc.8b10764 • Publication Date (Web): 23 Jan 2019 Downloaded from http://pubs.acs.org on January 25, 2019

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The Journal of Physical Chemistry

Large Electrostrain from Ferroelectric Aging Effect around Morphotropic Phase Boundary Yang Yang1,*, Zhijian Zhou1,ϯ, Lipeng Xin1, Chao Zhou1, Lixue Zhang1, Andong Xiao1, Xiaobing Ren1,2, †

1Multi-Disciplinary

Materials Research Center, Frontier Institute of Science and

Technology, and State Key Laboratory of Mechanical Behavior of Materials, Xi’an Jiaotong University, Xi’an 710049, China 2National

Institute for Materials Science, 1-2-1 Sengen, Tsukuba, 305-0047, Ibaraki,

Japan

ABSTRACT:

A

intrinsic-acceptor-doped

large

electrostrain

morphotropic

of

phase

~0.245%

emerged

boundary

(MPB)

in

an

system

Ba(Ce0.1Ti0.9)O3-x(Ba0.7Ca0.3)TiO3 under an electric field of 30kV/cm at 0.1Hz. It is almost twice as that of hard lead zirconate titanates and larger than the strains of other barium titanate-based systems with either aging effect or MPB effect. This large electrostrain is induced by the coupling of aging effect and MPB effect in the MPB composition. More interestingly, it is found that, different from the aged single phase samples, the aged MPB sample shows a more obvious increase in electrostrain but a slighter decrease in saturation polarization. The explanation for this abnormal aging effect around MPB has been proposed based on the symmetry-conforming principle of point defects. This work demonstrates that the ferroelectric aging effect around 1

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MPB could be an effective tool to achieve large electrostrain in ferroelectrics.

1. INTRODUCTION As a kind of functional material that can actualize the converting from electrical voltage to mechanical strain,1,2 electromechanical materials have extensive applications in telecommunications, ultrasonic imagers, and actuators.1,3–5 Generally, the electric-field-induced strain (known as electrostrain) is one of the most valuable parameter of electromechanical materials.6–8 A large electrostrain is crucial to designing smart and miniaturized electromechanical energy conversion devices. Ferroelectric materials with asymmetric or polar structures are the mainstays of the electromechanical materials. The common approach to obtaining large electrostrain in ferroelectrics is to control the composition in the proximity of a morphotropic phase boundary (MPB), where the polarization state is extremely unstable and usually accompanied by the phase transition process under an external field.9–12 The MPB with the coexistence of different phases has been recognized as a “golden rule” to design ferroelectric materials with high performances. Therefore, since the discovery of Pb(Ti ,Zr)O3 in the 1950s, the MPB has been extensively studied in many ferroelectric systems.9,13,14 Furthermore, aging effect, the spontaneous change of ferroelectric, dielectric and piezoelectric properties with time, is a common phenomenon in ferroelectrics.1,15–18 It is an important issue for both fundamental and practical applications, which can strongly affect the properties of materials. Although, aging is usually regarded as an 2


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undesired effect due to its impacts on the reliability of ferroelectric devices,1 it is not always detrimental. In single ferroelectric phase region, the aging effect induced by acceptor-doping is utilized to obtain enhanced recoverable electrostrain owing to the point-defect-mediated reversible domain switching process.19–25 An interesting question arises that what is the impact of aging on the MPB and associated electrostrain performance. Does the reversible domain switching mechanism of aging effect still work in the MPB region? Here

we

design

a

lead-free

piezoelectric

system,

(1-x)Ba(Ti0.9Ce0.1)O3-x(Ba0.7Ca0.3)TiO3 (denoted as BTC-xBCT hereafter), to explore the aging effect around MPB. Unlike other (1-x)Ba(Ti,X)O3-x(Ba,Ca)TiO3 (X= Zr, Hf, Sn) systems, it is essential to note that there are inherent oxygen vacancies in BTC-xBCT system due to the concurrence of +4 and +3 valences of Ce cations. In this regard, this system is desirable to study the aging effect because it can exclude the impact of additional acceptor doping. The experimental results show that although all the aged samples present a double hysteresis loop, the aging effect is weaker at the MPB composition, in contrast with the single phase compositions. But the enhancement of electrostrain is more obvious in the MPB region and can reach up to 34%. This abnormal electrostrain enhancement can be ascribed to the coupling of morphotropic phase boundary and aging effect in the MPB sample. Based on the symmetry-conforming short-range ordering (SC-SRO) principle, we propose a possible mechanism for this unique behaviour.

3



2. EXPERIMENT The BTC-xBCT (0.1≤x≤0.85) system ceramics were fabricated via the conventional solid-state method using a stoichiometric mixture of BaCO3 (99.8%), TiO2 (99.8%), CaCO3 (99.8%) and CeO2 (99.99%) by ball milling processing. The following calcination and sintering were performed at 1350 oC and 1450 oC in air, respectively. The sintered samples were held at 300 oC for 2 hours and followed by air-quenching to room temperature acting as “unaged samples”. And then the unaged samples were aged at 22 oC for four weeks as the “aged samples”. The crystalline structures of different samples were determined by powder X-ray diffraction (XRD) using Cu Kα radiation (Shimadzu 7000, Japan) at room temperature, and the dielectric properties were evaluated using a HIOKI3532 LCR meter at 1 kHz. X-ray photoelectron spectroscopy (XPS) measurements were carried out with a spectrometer (AXIS ULtrabl, Kratos) with Al Kα radiation. Polarization hysteresis loops were measured using a ferroelectric test system (Radiant Workstation) and the bipolar electrostrain measurements were determined on a MTI-2000 photonic sensor.

3. RESULTS AND DISCUSSION Our target system is the solid solutions of two fixed terminals Ba(Ce0.1Ti0.9)O3 (abbreviated as BTC) and (Ba0.7Ca0.3)TiO3 (abbreviated as BCT). The XRD patterns of the BTC-xBCT system samples indicate that pure perovskite phase was obtained for all ceramics (see supporting information Fig. S1). And the different valence states of Ce ions are confirmed by X-ray photoelectron spectra (see supporting information 4


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Fig. S2). As shown in Fig. 1(a), the phase diagram of this system was established by combining the XRD pattern (Fig. 1(b)) and corresponding temperature-dependent dielectric

permittivity

results

(Fig.

1(c)).

It

is

characterized

by

a

ferroelectric-ferroelectric phase boundary separating a ferroelectric rhombohedral (R) phase and a ferroelectric tetragonal (T) phase around x ~0.34. According to the phase diagram, the samples 0.1BCT with rhombohedral structure, 0.4BCT around MPB, and 0.7BCT with tetragonal phase were selected as typical specimens for the following aging effect research.

Figure 1. (a) Phase diagram of the lead-free Ba(Ti0.9Ce0.1)O3-x(Ba0.7Ca0.3)TiO3 system; (b) XRD profiles of BTC-0.1BCT, BTC-0.4BCT, BTC-0.7BCT ceramics of (200), (220), (222) peaks at room temperature; (c) Temperature-dependent dielectric permittivity upon cooling and heating process of BTC-0.1BCT, BTC-0.4BCT, BTC-0.7BCT samples, respectively.

5



Figure 2(a-c) shows the comparison of polarization hysteresis loops of the selected typical specimens at unaged and aged state. For the unaged samples, when an electric field is applied, the increase of electric field could enhance the polarization values. When the field drops to zero, there is the intrinsic remnant polarization due to the irreversible domain switching process. All the samples present the normal polarization hysteresis loops except for the 0.1BCT “unaged sample”, which may change into weak aged state during the air-quenching process. In contrast, after aged for enough time, all samples present double polarization hysteresis loops. The polarization value increases to maximum with the electric field increasing to maximum but drops to zero as the field decreases to zero. It is interesting to note that weaker aging effect exists in the MPB region, which is manifested in the less “pinching” of P-E loop and the slighter decrease in saturation polarization value as compared with single phase region samples. The electrostrain behaviors for different specimens at unaged and aged state are shown as Fig. 2(d-f). Different from the “butterfly-shaped” strain curves of the unaged ferroelectrics, the aged samples show the recoverable electrostrain curves, except for the MPB (0.4BCT) sample. The aged MPB ferroelectric does not present the perfect recoverable electrostrain curve, but shows the maximum enhancement of electrostrain up to 34%. The obtained electrostrain value of aged MPB (0.4BCT) sample is almost twice as large as that of hard lead zirconate titanate.

6


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Figure 2. Polarization hysteresis loops for unaged and aged (a) BTC-0.1BCT, (b) BTC-0.4BCT, (c) BTC-0.7BCT ceramics; Electrostrain of unaged and aged (d) BTC-0.1BCT, (e) BTC-0.4BCT, (f) BTC-0.7BCT ceramics at room temperature (RT, 22oC) and 10Hz.

We further investigated the stability of electrostrain of the aged samples upon different electric field frequencies and cyclic numbers. As shown in Fig. 3(a1-a3), it is found that the aging-induced large electrostrain persists down to the ultra-low frequency (~0.1Hz) in all samples. As the field frequency decreases, the strain level of all samples increases. Surprisingly, this effect is particularly noticeable in the 0.4BCT sample with a large strain up to 0.245% and corresponding d33* (d33* =Smax/Emax) up to 817pC/N under 30 kV/cm electric field. The field frequency dependent electrostrain is vital for the practical applications. In addition, the field cycling stability of electrostrain is another important parameter for the applications. The obtained strain value is increased with the increasing of cyclic number (Fig. 3(b1-b3)). The strain value of the aged MPB sample reaches 0.217% after 100 electric field cycles. 7



Figure 3. Field frequency dependent electrostrain for the aged (a1) BTC-0.1BCT, (a2) BTC-0.4BCT, (a3) BTC-0.7BCT samples; Field cyclic number dependence of electrostrain for aged (b1) BTC-0.1BCT, (b2) BTC-0.4BCT, (b3) BTC-0.7BCT ceramics.

The phenomenon of electrostrain enhancement of the aged MPB sample verifies that the point-defect-mediated reversible domain switching mechanism can still work in the MPB region. Next, based on the symmetry-conforming short-range ordering principle (SC-SRO) of point defects, we propose a possible microscopic explanation for the observed unusual aging effect around MPB. The SC-SRO principle describes a relationship between crystal symmetry and the statistical short-range-order point defects (here point defects include vacancies, dopants) symmetry.18–21 The point defects tend to adopt the statistical symmetry to follow the crystal symmetry in the equilibrium state (after aging). Consequently, the polar defect symmetry in the well-aged crystal creates a defect polarization (PD) aligning along the spontaneous polarization (PS) direction, which can stabilize the existing domains and create a 8


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restoring force for a reverse domain switching.21–24 For the unaged single phase samples, defects cannot provide the restoring force during domain switching process due to their statistical cubic symmetry.21,23 The quantity of non-180o domain is decreased after first applying and removing the electric field cycle. Because the exchange of non-equal crystallographic axes of the non-180o domain can generate large strain effect,19,25 the electrostrain of the unaged single phase samples is significantly decreased after the first electric field cycle. For the aged single phase samples, defect symmetry follows the crystal symmetry, which can provide the significant restoring force during domain switching process. The restoring force can reverse the domain switching and re-establish the initial domain state.19,21 And the reversible non-180o domains switching contributes to the enhanced recoverable electrostrain of the aged single phase samples. It should be mentioned that although the restoring force of aged samples generates the enhancement effect in electrostrain in most of cases, it is also a resistance hindering the domain switching process and stabilizing the domain configuration.21,26 Therefore, the maximum enhancement of electrostrain should appear in an optimal state which possesses the appropriate quantity of non-180o domains and relative low resistance. In comparison with the single crystal symmetry ferroelectrics, the MPB region ferroelectrics have the coexistence of tetragonal and rhombohedral crystal symmetry. After aged for enough time in the ferroelectric state, defect symmetry follows the crystal symmetry (see Fig. 4). Consequently, the polar tetragonal defect symmetry in the well-aged tetragonal crystal part creates a defect polarization PD aligning along the 9



spontaneous polarization PS direction . The polar rhombohedral defect symmetry in the well-aged rhombohedral crystal part creates a defect polarization PD aligning along the spontaneous polarization PS direction .21 Due to the unstable state of the MPB sample, there exists the phase transition when applying electric field (here assuming the phase transition from tetragonal phase to rhombohedral phase).26,27 In this case, part of defects symmetry is not consistent with the crystal symmetry. It is unable to provide an effective restoring force for the reversible switching of domains. Thus the aged MPB sample possesses the weaker restoring force as compared with single phase region samples. And the weaker restoring force of MPB sample is responsible for the weaker aging effect. As mentioned above, the weaker restoring force of MPB sample corresponds to the weaker resistance (see Fig. 4), which makes the domain switching easier and allows more domains to switch as compared with single phase region samples. Simultaneously, the weaker restoring force and reversible phase transition can guarantee the appropriate quantity of non-180o domains of MPB specimen.26,27 Thus the unstable structure in MPB region and the restoring force from defects give rise to a synergetic effect for the observed large electrostrain enhancement of MPB sample. It should be noticed that the quantity of non-180o domains has no effect on saturation polarization value. The aged MPB sample with weaker resistance shows the less decrease in saturation polarization.

10


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Figure 4. Reversible domain switching mechanism in both single phase region and MPB region. Large square represents single domain, PS refers to spontaneous polarization. Small rectangle represents defect polarization (PD), and the area of small rectangles indicates the magnitude of the defect polarization. The color (blue or red) indicates different polarization directions.

The mechanism for the increased strain behaviors of the aged samples with low-frequency field or increased field cyclic number is similar, both due to the migration of a part of oxygen vacancies during the slow process. Low-frequency field or filed cycling may assist some defect dipoles to align along the external electric field direction. This process can change the symmetry-conforming configuration, leading to a decreased resistance. For the unstable MPB region, it will be more sensitive to the fluctuation of resistance. Thus the MPB sample presents a more pronounced strain enhancement effect than others. In this work, the largest strain (~0.245%) is obtained (d33* ~ 817pC/N) in the MPB composition at the low frequency 0.1Hz. This remarkable result can rival the strain level of classical soft PZT ceramics (~ 0.2%) and is close to the theoretical value of BaTiO3 ceramic (~ 0.368%). 11



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4. CONCLUSIONS In summary, the aging effect has been systemically studied in an intrinsic-acceptor-doped

morphotropic

phase

boundary

(1-x)Ba(Ti0.9Ce0.1)O3-x(Ba0.7Ca0.3)TiO3 system. Aging-induced double hysteresis loops can be clearly observed in both single phase region and MPB region. Due to the inherent unstable state of MPB region, the most pronounced increase in electrostrain occurs in the aged MPB sample (~0.245%) with the most unconspicuous decrease in saturation polarization. This abnormal phenomenon can be explained based on the symmetry-conforming short-range ordering principle. In light of this study, the coupling of aging effect and MPB effect will be a powerful tool for tuning large electrostrain in perovskite oxides.

AUTHOR INFORMATION Corresponding Authors *E-mail:

[email protected]. Tel: +81-29-859-3312.

ϯE-mail:


†E-mail:


Notes The authors declare no competing financial interest.

ACKNOWLEDGEMENTS 12


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The authors gratefully acknowledge the support of the National Natural Science Foundation of China (51320105014, 51321003, 51431007) and Country China Scholarship Council.

Supporting Information Available: More detailed information on the XRD results and X-ray photoelectron spectra

REFERENCES (1) Uchino, K. Ferroelectric Devices; CRC Press: Boca Raton, FL, 2000; Vol. 16. (2) Gandhi, M. V.; Thompson, B. S. Smart Materials and Structures; Academic: London, 1992. (3) Cross, L. E. Ferroelectric Materials for Electromechanical Transducer Applications. Mater. Chem. Phys. 1996, 43, 108–115. (4) Whatmore, R. W.; Osbond, P. C.; Shorrocks, N.M. Ferroelectric Materials for Thermal IR Detectors. Ferroelectrics 1987, 76, 351–367. (5) Uchino, K. Piezoelectric Actuators and Ultrasonic Motors; Kluwer Academic Publishers: London, 1996. (6) Narayan, B.; Malhotra, J. S.; Pandey, R.; Yaddanapudi, K.; Nukala, P.; Dkhil, B.; Senyshyn, A.; Ranjan, R. Electrostraion in Excess of 1% in Polycrystalline Piezoelectrics. Nat. Mater. 2018, 17, 427–431. (7) Jo, W.; Dittmer, R.; Acosta, M.; Zang, J.; Groh, C.; Sapper, E.; Wang, K.; Rodel, J. Giant Electric-field-induced Strains in Lead-free Ceramics for Actuator Applications – Status and Perspective. J. Electroceram. 2012, 29, 71–93. 13



(8) Gao, J.; Xue, D.; Liu, W.; Zhou, C.; Ren, X. Recent Progress on BaTiO3-based Piezoelectric Ceramics for Actuator Applications. Actuators 2017, 6, 24. (9) Liu, W.; Ren, X. Large Piezoelectric Effect in Pb-Free Ceramics. Phys. Rev. Lett. 2009,103, 257602. (10) Zhao, L.; Ke, X.; Wang, W.; Zhang, L.; Zhou, C.; Zhou, Z.; Zhang, L.; Ren, X. Electrostrain Enhancement at an Invisible Boundary in a Single Ferroelectric Phase. Phys. Rev. B 2017, 95, 020101. (11) Ahart, M.; Somayazulu, M.; Cohen, R. E.; Ganesh, P.; Dera, P.; Mao H.; Hemley, R. J.; Ren, Y.; Liermann, P.; Wu, Z. Origin of Morphotropic Phase Boundaries in Ferroelectrics. Nature 2008, 451, 545–548. (12) Damjanovic, D. A Morphotropic Phase Boundary System Based on Polarization Rotation and Polarization Extension. Appl. Phys. Lett. 2010, 97, 062906. (13) Zeches, R. J.; Rossell, M. D.; Zhang, J. X.; Hatt, A. J.; He, Q.; Yang, C.-H.; Kumar, A.; Wang, C. H.; Melville, A.; Adamo, C.; Sheng, G.; Chu, Y.-H.; Ihlefeld, J. F.; Erni, R.; Ederer, C.; Gopalan, V.; Chen, L. Q.; Schlom, D. G.; Spaldin, N. A.; Martin, L. W.; Ramesh, R. A Strain-Driven Morphotropic Phase Boundary in BiFeO3. Science 2009, 326, 977–980. (14) Eitel, R. E.; Randall, C. A.; Shrout, T. R.; Rehrig, P. W.; Hackenberger, W.; Park, S. New High Temperature Morphotropic Phase Boundary Piezoelectrics Based on Bi(Me)O3-PbTiO3 ceramics. Japan. J. Appl. Phys. 2001, 40, 10. (15) Colla, E. V.; Chao, L. K.; Weissman, M. B.; Viehland, D. D. Aging in a Relaxor Ferroelectric: Scaling and Memory Effects. Phys. Rev. Lett. 2000, 85, 3033–3036. 14


Page 14 of 16

Page 15 of 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(16) Lambeck, P. V.; Jonker, G. H. The Nature of Domain Stabilization in Ferroelectric Perovskites. J. Phys. Chem. Solid. 1986, 47, 453–461. (17) Bradt, R. C.; Ansell, G. S. Aging in Tetragonal Ferroelectric Barium Titanate. J. Am. Ceram. Soc. 1969, 52, 192–199. (18) Xue, D.; Gao, J.; Zhang, L.; Bao, H.; Liu, W.; Zhou, C.; Ren, X. Aging Effect in Paraelectric State of Ferroelectrics: Implication for a Microscopic Explanation of Ferroelectric Deaging. Appl. Phys. Let. 2009, 94, 082902. (19) Ren, X. Large Electric-field-induced Strain in Ferroelectric Crystals by Point-defect-mediated Reversible Domain Switching. Nat. Mater. 2004, 3, 91. (20) Feng, Z.; Or, S. W. Aging-induced Defect-mediated Double Ferroelectric Hysteresis Loops and Large Recoverable Electrostrains in Mn-doped Orthorhombic KNbO3-based Ceramics. J. Alloy. Compd. 2009, 480, L29–L32. (21) Zhang, L.; Ren, X. In situ Observation of Reversible Domain Switching in Aged Mn-doped BaTiO3 Single Crystals. Phys. Rev. B 2005, 71, 174108. (22) Zhang, L.; Chen, W.; Ren, X. Large Recoverable Electrostrain in Mn-doped (Ba,Sr) TiO3 Ceramics. Appl. Phys. Lett. 2004, 85, 5659–5660. (23) Zhang, L.; Ren, X. Aging Behavior in Single-domain Mn-doped BaTiO3 Crystals: Implication for a Unified Microscopic Explanation of Ferroelectric Aging. Phys. Rev. B 2006, 73, 094121. (24) Feng, Z.; Ren, X. Striking Similarity of Ferroelectric Aging Effect in Tetragonal, Orthorhombic and Rhombohedral Crystal Structures. Phys. Rev. B 2008, 77, 134115. (25) Park, S. E., Wada, S., Cross, L. E., Shrout, T. R. Crystallographically engineered 15



BaTiO3 single crystals for high-performance piezoelectrics. J. Appl. Phys. 1999, 86, 2746–2750. (26) Fan, Z., Tan, X.

In-situ TEM study of the aging micromechanisms in a

BaTiO3-based lead-free piezoelectric ceramic. J. Eur. Ceram. Soc. 2018, 38, 3472– 3477. (27) Liu, X., Tan, X. Giant Strains in Non-Textured (Bi1/2Na1/2)TiO3-Based Lead-Free Ceramics. Adv. Mater. 2016, 28, 574–578.

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Large Electrostrain from Ferroelectric Aging Effect around

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