PZT Nanorods Research Articles

Enhanced intrinsic piezoelectric response in (001)-epitaxial single c-domain Pb(Zr,Ti)O3 nanorods

In this study, (001)-epitaxial tetragonal phase Pb(Zr, Ti)O3 (PZT) nanorods were fabricated on SrRuO3/SrTiO3 substrates by pulsed laser deposition. The PZT nanorods were self-assembled and grown on the substrate at an elevated oxygen pressure, and showed a complete c-domain structure. Time-resolved x-ray diffraction measurements under an applied electric field show that the fabricated PZT nanorods exhibit a piezoelectric constant, d33, that is significantly higher than that of thin PZT films and comparable to that for unclamped single-domain bulk crystals, which is thought to be due to a significant reduction in substrate clamping. The obtained results demonstrate that the self-assembled nanorods can achieve an enhanced intrinsic piezoelectric response, which makes them attractive for a range of practical applications.

Wafer‐Scale Single‐Crystalline Ferroelectric Perovskite Nanorod Arrays

1D ferroelectric nanostructures are promising for enhanced ferroelectric and piezoelectric performance on the nanoscale, however, their synthesis at the wafer scale using industrially compatible processes is challenging. In order to advance the nanostructure‐based electronics, it is imperative to develop a silicon‐compatible growth technique yielding high volumetric density and an ordered arrangement. Here, a major breakthrough is provided in addressing this need and ordered and close‐packed single crystalline ferroelectric nanorod arrays, of composition PbZr0.52Ti0.48O3 (PZT), grown on commercial grade 3 in. silicon wafer are demonstrated. PZT nanorods exhibit enhanced piezoelectric and ferroelectric performance compared to thin films of similar dimensions. Sandwich structured architecture utilizing 1D PZT nanorod arrays and 2D reduced graphene oxide thin film electrodes is fabricated to provide electrical connection. Combined, these results offer a clear pathway toward integration of ferroelectric nanodevices with commercial silicon electronics.

Flexible Nanocomposite Generator Using PZT Nanorods and Ag Nanowires

This study presents a piezoelectric composite generator using PDMS polymer, PZT nanorods, and Ag nanowires. To enhance output power of the generator, we inserted the Ag NWs into the PDMS‐PZT composite, which play very important roles in our generator: First, it enables the PZT NRs well distributed in PDMS polymer. Second, it is to reinforce the applied stress of the device by enhancing its flexibility. Finally, conduction paths formed by the Ag networks can reduce the internal resistance of the device. To assess these effects, we have compared and evaluated output voltage and current of four different generators.

Domain structure of tetragonal Pb(Zr,Ti)O3 nanorods and its size dependence

We fabricated {100} Pb(Zr0.35Ti0.65)O3 (PZT) nanorods by partly etching a film grown on a Nb-doped SrTiO3 substrate using a focused ion beam, followed by annealing to recover the etching damage and promote the formation of a stable domain structure in the form of nanorods. The application of synchrotron micro-X-ray diffraction enabled the detection of the diffraction intensity from a single nanorod, which allowed us to clarify the size dependence of the domain structure of the fabricated nanorods. We found that the a-domain fraction in the tetragonal PZT nanorods decreased with decreasing rod width and that an exclusively c-domain structure was formed in nanorods of ≤1 µm width. The preferred formation of the c-domain in these nanorods can be rationalized in terms of the large depolarizing field in the a-domain and/or the in-plane compressive strain near the PZT/substrate interface.

Template-free formation of Pb (Zr0.52Ti0.48) O3 (PZT) nanorods

Lead Zirconate titanate nanorods Pb (Zr0.52Ti0.48) O3 were synthesized via a molten salt route. In this research, milled PZT nanopowder and sodium chloride were mixed together with triton X-100 as surfactant. In the first stage, the starting materials at molar ratio 1:5:10 (PZT:NaCl:Triton X-100) was heat treated at 800 °C for 3, 6 and 12 h. In the second stage the molar ratio of starting materials was fixed at 1:10:15 (PZT:NaCl:Triton X-100) following the same heat treatment plans. The resulting products were characterized using X-ray diffraction (XRD) and scanning electron microscopy. XRD patterns confirmed the presence of both monoclinic and triclinic structures. No PZT nanorods were produced when short time (3 h) heat treatment was applied regardless of the molar ratio of the starting materials. Cylindrical nanorods with average length of 2 μm and diameter of 50 nm were produced when the molar ratio was adjusted at 1:5:10 and heat treatment was carried out for 6 h. The nanorods are seemed to be partly destroyed when the heat treatment time was extended to 12 h. Nanorods with square shape cross section were achieved when the molar ratio was adjusted at 1:10:15 where the diameter and length were found to be 40–400 and 60–600 nm with heat treatment time of 6 and 12 h respectively.

(001)-orientation single crystalline Pb(Zr0.3Ti0.7)O3 pyroelectric nanorod array synthesized by hydrothermal reaction

The fabrication and pyroelectric coefficient of Pb(Zr0.3Ti0.7)O3 (PZT) nanorod array on Nb:SrTiO3 (NSTO) substrates were reported. XRD and TEM revealed that PZT nanorods were (001) orientation single crystalline. Dense PZT nanorod array were synthesized on NSTO using optimal 0.8 g/L poly(vinyl alcohol) (PVA) and 3.2 g/L poly(acrylate acid) (PAA). Maximum pyroelectric coefficient, 5.8 × 10−9 C/(cm2·K), was measured for samples synthesized at 230 °C and poled under 5 V. The single crystalline PZT nanorod array material has potential application in small spatial (1–10 µm) infrared detectors, benefiting to achieve distinguished detector performances.

J2240201 PZT薄膜及びナノロッドの圧電特性に及ぼす基板拘束の影響([J224-02]『マイクロ・ナノ機械の信頼性』のための材料創製・測定・解析技術 マイクロ・ナノ実験力学と機能材料)

J2240201 PZT薄膜及びナノロッドの圧電特性に及ぼす基板拘束の影響([J224-02]『マイクロ・ナノ機械の信頼性』のための材料創製・測定・解析技術 マイクロ・ナノ実験力学と機能材料)

A new method of depositing high figure-of-merit porous PZT pyroelectric thick film using [001]-oriented PZT nanorod by electrophoresis deposition

The effects of hydrothermal synthesized [001]-oriented PZT nanorods on the pyroelectric properties of PZT thick film fabricated by electrophoresis deposition were studied in a range from 750 to 900 °C. It was revealed by scanning electron microscopy that the pores are mainly distributed in the film body but not at the electrode interface, which would improve the adhesion and electric contact between the thick film and electrode. The formation and distribution of the pores resulted from the PZT nanorods were schematically explained. It was found that the relative dielectric constant (er) of the PZT nanorod-doping film sintered at 800 °C was lowered by approximate 46.5 %. Accordingly, the calculated figures of merit for voltage responsivity (FV) and detectivity (FD) were improved by 125 and 114 %, respectively. These results demonstrated that a new way to deposit PZT porous thick film with low dielectric constant and high figures of merit was established.