Achieving Single-Crystal Performance in Polycrystalline Materials: Mechanistic Characterisation Using Critus In-Situ Measurement Technology

A major advance published in Science shows that textured PZT ceramics can rival single crystals in piezoelectric performance, enabled by in-situ measurements using Critus Pty Ltd's Transmission Geometry Cell, revealing polarization rotation as the key mechanism.

by John Daniels · June 24th, 2025 – 4 minutes to read

Textured PZT Ceramics

Polarization Rotation

In-Situ X-Ray Diffraction

Based on: Li, J., et al. "Lead zirconate titanate ceramics with aligned crystallite grains." Science 380, 87–93 (2023). DOI: 10.1126/science.adf6161

Instrumentation: Critus Transmission Geometry Cell

Revolutionary Texturing Process Yields Unprecedented Performance

A landmark study published in *Science* has demonstrated that polycrystalline lead zirconate titanate (PZT) ceramics can achieve piezoelectric performance comparable to single crystals through a novel seed-passivated texturing process. This breakthrough, achieved by researchers from Xi'an Jiaotong University and international collaborators, relied critically on real-time structural characterization using Critus Pty Ltd's Transmission Geometry Cell at the European Synchrotron Radiation Facility (ESRF) to understand the mechanisms of material response.

The Research Achievement

The research team, led by Professor Fei Li, successfully developed textured PZT ceramics with extraordinary properties:

Piezoelectric coefficient d₃₃ of 760 pC/N
Electromechanical coupling factor k₃₃ of 0.85
Voltage coefficient g₃₃ of 100 mVm/N
Curie temperature of 360°C

These values represent a 60-100% improvement over conventional PZT ceramics while maintaining high temperature stability - a combination previously thought impossible. The textured ceramics achieved >99% crystallographic alignment along the <001> direction, resulting in strain levels exceeding 0.57% at 50 kV/cm electric field.

Critical Role of Critus Transmission Geometry Cell

The Critus Transmission Geometry Cell provided essential capabilities that made these challenging experiments possible:

High-Energy X-ray Transmission Measurements

The Critus system's transmission geometry design was ideally suited for the high-energy X-rays at ESRF's ID15A beamline, enabling:

Real-time monitoring of lattice strain evolution under electric fields up to 50 kV/cm
Simultaneous texture and strain information at multiple crystallographic orientations
Precise measurement of polarization rotation mechanisms
Detection of domain switching behavior in textured grains

Critus T-Cell at ESRF Facility

Synchronized Electromechanical Characterization

The integrated electrical measurement capabilities allowed researchers to:

Apply controlled electric fields up to ±7.5 kV while collecting diffraction data
Measure strain-electric field hysteresis loops in-situ
Correlate structural changes with macroscopic electromechanical response
Verify the polarization rotation mechanism driving enhanced performance

Temperature-Dependent Studies

The system's temperature capability (room temperature to 200°C) enabled:

Characterization of material strain mechanisms across a broad temperature range
Validation of consistent material performance from room-temperature to 200°C
Confirmation of stable rhombohedral phase structure

Technical Insights from In-Situ Measurements

The Critus instrumentation revealed crucial mechanistic insights:

Polarization Rotation Mechanism: Real-time diffraction showed that enhanced strain arises from polarization rotation from <111> rhombohedral directions toward the [001] field direction, rather than domain switching.
Minimal Domain Switching: The (111) diffraction peaks remained stable under electric field, confirming that grain orientation prevented conventional 71° domain switching.
Reversible Lattice Strain: The system captured 0.47% reversible lattice strain with minimal remnant strain, demonstrating the elastic nature of the polarization rotation process.
Texture Quality Validation: Multi-angle diffraction measurements confirmed >94% grain alignment and quantified the 6% misaligned grain fraction.

Image from Science Paper

Advantages of the Critus Transmission Geometry Design

The Critus Transmission Geometry Cell offered several key advantages for this study:

High-Field Capability: Applied voltages up to ±7.5 kV enabled full characterization of the polarization rotation process
Large Angular Range: Wide scattering angle access allowed comprehensive reciprocal space mapping
Silicon Oil Bath: Prevented electrical breakdown at high fields while maintaining X-ray transparency
Compact Design: Integrated seamlessly with synchrotron beamlines for efficient data collection
Safety Interlocks: Ensured safe operation with high voltages in the experimental environment

Impact on Piezoelectric Technology

This research demonstrates how advanced in-situ characterization tools enable breakthrough discoveries in materials science. The ability to achieve single-crystal-like performance in polycrystalline ceramics while maintaining high Curie temperatures promises to revolutionize:

Medical ultrasound transducers requiring high sensitivity and thermal stability
Precision actuators for semiconductor manufacturing
High-temperature sensors for automotive and aerospace applications
Energy harvesting devices with enhanced efficiency
Next-generation SONAR systems

Future Directions

The success of this work opens new avenues for materials development. The Critus Transmission Geometry Cell's ability to provide real-time structural insights under extreme electrical conditions will be crucial for:

Optimizing texturing processes for other piezoelectric systems
Developing lead-free alternatives with comparable performance
Understanding domain engineering in complex ferroelectric compositions
Advancing multi-functional materials with coupled properties

Conclusion

The groundbreaking results achieved in developing textured PZT ceramics underscore the critical importance of advanced in-situ characterization in modern materials research. Critus Pty Ltd's Transmission Geometry Cell, with its unique combination of high-field capability, temperature control, and compatibility with high-energy X-ray scattering geometries, proved instrumental in unlocking the mechanisms behind this revolutionary advance in piezoelectric materials.

As the field moves toward even more complex material systems and extreme operating conditions, the demand for sophisticated characterization tools will continue to grow. Critus remains at the forefront of enabling these discoveries through innovative instrumentation design.

For more information about Critus Pty Ltd's Transmission Geometry Cell and other in-situ diffraction systems, visit critus.com.au or Contact Us

John Daniels

CEO, Critus Pty Ltd

John Daniels is currently an Associate Professor at the UNSW School of Materials Science and Engineering. John was awarded his PhD in 2007 from the School of Physics at Monash University, Melbourne, Australia for work in the field of time-resolved neutron scattering in ferroelectric materials. John spent three years as a postdoctoral researcher within the Structure of Materials group at the European Synchrotron Radiation Facility, Grenoble, France. During this time John specialised in the application of high-energy x-ray scattering techniques to the study of functional and mechanical properties of materials. John's current research is in the application of advanced neutron and x-ray scattering techniques for multi-length-scale structural analysis of functional materials.