Acting like thermal resistances, ferroelectric domain walls can be manipulated to realize dynamic modulation of thermal conductivity (
AC-poling of Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3(PIN-PMN-PT) single crystals with a thickness of 0.06–0.16 mm was studied in this paper. Compared with DC-poled samples, enhancements in piezoelectric and dielectric properties can be obtained when the thickness is above 0.1 mm. However, inconsistency in poling effects was found in the crystals with thickness below 0.1 mm. To elucidate why such scaling effect arises, surface roughness was measured by an atomic force microscopy to correlate surface morphology and poling effects. It was found that non-uniform surface roughness led to inconsistent and decreased properties. Furthermore, temperature-dependent dielectric permittivity spectra were measured to explore how crystal thickness affects the thermal stability of ferroelectric phases. It is noted that complex changes in crystallographic symmetries emanate by decreasing thickness. Such phenomena can be attributed to more influential effects of surface morphology when thickness is reduced. We hope this work suggests a clue for solving the scaling effects of AC-poling on relaxor-PbTiO3single crystals.
more » « less- NSF-PAR ID:
- 10365087
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- Applied Physics Letters
- Volume:
- 120
- Issue:
- 14
- ISSN:
- 0003-6951
- Page Range / eLocation ID:
- Article No. 142901
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract k ), which is essential for developing novel phononic circuits. Despite the interest, little attention has been paid to achieving room‐temperature thermal modulation in bulk materials due to challenges in obtaining a high thermal conductivity switching ratio (k high/k low), particularly in commercially viable materials. Here, room‐temperature thermal modulation in 2.5 mm‐thick Pb(Mg1/3Nb2/3)O3–x PbTiO3(PMN–x PT) single crystals is demonstrated. With the use of advanced poling conditions, assisted by the systematic study on composition and orientation dependence of PMN–x PT, a range of thermal conductivity switching ratios with a maximum of ≈1.27 is observed. Simultaneous measurements of piezoelectric coefficient (d 33) to characterize the poling state, domain wall density using polarized light microscopy (PLM), and birefringence change using quantitative PLM reveal that compared to the unpoled state, the domain wall density at intermediate poling states (0<d 33<d 33,max) is lower due to the enlargement in domain size. At optimized poling conditions (d 33,max), the domain sizes show increased inhomogeneity that leads to enhancement in the domain wall density. This work highlights the potential of commercially available PMN–x PT single crystals among other relaxor‐ferroelectrics for achieving temperature control in solid‐state devices. -
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Abstract Piezoelectric materials enable the conversion of mechanical energy into electrical energy and vice‐versa. Ultrahigh piezoelectricity has been only observed in single crystals. Realization of piezoelectric ceramics with longitudinal piezoelectric constant (
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Abstract Lead‐based relaxor ferroelectrics are characterized by outstanding piezoelectric and dielectric properties, making them useful in a wide range of applications. Despite the numerous models proposed to describe the relation between their nanoscale polar structure and the large properties, the multiple contributions to these properties are not yet revealed. Here, by combining atomistic and mesoscopic‐scale structural analyses with macroscopic piezoelectric and dielectric measurements across the (100–
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Ever-increasing demands for energy, particularly being environmentally friendly have promoted the transition from fossil fuels to renewable energy.1Lithium-ion batteries (LIBs), arguably the most well-studied energy storage system, have dominated the energy market since their advent in the 1990s.2However, challenging issues regarding safety, supply of lithium, and high price of lithium resources limit the further advancement of LIBs for large-scale energy storage applications.3Therefore, attention is being concentrated on an alternative electrochemical energy storage device that features high safety, low cost, and long cycle life. Rechargeable aqueous zinc-ion batteries (ZIBs) is considered one of the most promising alternative energy storage systems due to the high theoretical energy and power densities where the multiple electrons (Zn2+) . In addition, aqueous ZIBs are safer due to non-flammable electrolyte (e.g., typically aqueous solution) and can be manufactured since they can be assembled in ambient air conditions.4As an essential component in aqueous Zn-based batteries, the Zn metal anode generally suffers from the growth of dendrites, which would affect battery performance in several ways. Second, the led by the loose structure of Zn dendrite may reduce the coulombic efficiency and shorten the battery lifespan.5
Several approaches were suggested to improve the electrochemical stability of ZIBs, such as implementing an interfacial buffer layer that separates the active Zn from the bulk electrolyte.6However, the and thick thickness of the conventional Zn metal foils remain a critical challenge in this field, which may diminish the energy density of the battery drastically. According to a theretical calculation, the thickness of a Zn metal anode with an areal capacity of 1 mAh cm-2is about 1.7 μm. However, existing extrusion-based fabrication technologies are not capable of downscaling the thickness Zn metal foils below 20 μm.
Herein, we demonstrate a thickness controllable coating approach to fabricate an ultrathin Zn metal anode as well as a thin dielectric oxide separator. First, a 1.7 μm Zn layer was uniformly thermally evaporated onto a Cu foil. Then, Al2O3, the separator was deposited through sputtering on the Zn layer to a thickness of 10 nm. The inert and high hardness Al2O3layer is expected to lower the polarization and restrain the growth of Zn dendrites. Atomic force microscopy was employed to evaluate the roughness of the surface of the deposited Zn and Al2O3/Zn anode structures. Long-term cycling stability was gauged under the symmetrical cells at 0.5 mA cm-2for 1 mAh cm-2. Then the fabricated Zn anode was paired with MnO2as a full cell for further electrochemical performance testing. To investigate the evolution of the interface between the Zn anode and the electrolyte, a home-developed in-situ optical observation battery cage was employed to record and compare the process of Zn deposition on the anodes of the Al2O3/Zn (demonstrated in this study) and the procured thick Zn anode. The surface morphology of the two Zn anodes after circulation was characterized and compared through scanning electron microscopy. The tunable ultrathin Zn metal anode with enhanced anode stability provides a pathway for future high-energy-density Zn-ion batteries.
Obama, B., The irreversible momentum of clean energy.
Science 2017, 355 (6321), 126-129.Goodenough, J. B.; Park, K. S., The Li-ion rechargeable battery: a perspective.
J Am Chem Soc 2013, 135 (4), 1167-76.Li, C.; Xie, X.; Liang, S.; Zhou, J., Issues and Future Perspective on Zinc Metal Anode for Rechargeable Aqueous Zinc‐ion Batteries.
Energy & Environmental Materials 2020, 3 (2), 146-159.Jia, H.; Wang, Z.; Tawiah, B.; Wang, Y.; Chan, C.-Y.; Fei, B.; Pan, F., Recent advances in zinc anodes for high-performance aqueous Zn-ion batteries.
Nano Energy 2020, 70 .Yang, J.; Yin, B.; Sun, Y.; Pan, H.; Sun, W.; Jia, B.; Zhang, S.; Ma, T., Zinc Anode for Mild Aqueous Zinc-Ion Batteries: Challenges, Strategies, and Perspectives.
Nanomicro Lett 2022, 14 (1), 42.Yang, Q.; Li, Q.; Liu, Z.; Wang, D.; Guo, Y.; Li, X.; Tang, Y.; Li, H.; Dong, B.; Zhi, C., Dendrites in Zn-Based Batteries.
Adv Mater 2020, 32 (48), e2001854.Acknowledgment
This work was partially supported by the U.S. National Science Foundation (NSF) Award No. ECCS-1931088. S.L. and H.W.S. acknowledge the support from the Improvement of Measurement Standards and Technology for Mechanical Metrology (Grant No. 22011044) by KRISS.
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Abstract The discovery of superconductivity in twisted graphene bilayers with a magic twisting angle ≈1.1° has opened up a wide range of potential twistronic device possibilities. In this work, the twisting effects in spintronic devices are explored. In particular, a material prototype integrating spintronics, straintronics, and twistronics is developed by stacking a twisted CoFe2O4(CFO) bilayer membrane on a Pb(Mg1/3Nb2/3)O3‐PbTiO3(PMN‐PT) membrane. Phase‐field simulations are performed to study the magnetic domain configurations and switching in CFO bilayers under piezostrains. An emerging interlayer parallel‐to‐antiparallel magnetic transition of the twisted CFO bilayer induced by appropriate piezostrain pulses generated from the PMN‐PT membrane is discovered. Such a strain‐induced parallel‐to‐antiparallel magnetic transition is non‐volatile and reversible, arising from the synergistic interaction among spin, strain, and twisting order parameters. The present work provides a paradigm for designing novel spinotropic devices by taking advantage of the emerging phenomena generated by twisting.
