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Updated: Jan 7, 2026
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Synthesis and Microdiffraction at Extreme Pressures and Temperatures
Published on: October 7, 2013
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Structural Evolution of CoMoO4 under Pressure: Multiphase Transformations and Reconstructive Behaviors.
Xinxin Gao1,2, Zhi Zheng1, Mengjun Xiong1,2
1Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya 572000, China.
Inorganic Chemistry
|December 29, 2025
Summary
Thin cobalt molybdate (CoMoO4) samples show two phase transitions under high pressure, demonstrating enhanced structural resistance. This research clarifies their behavior under extreme conditions.
Area of Science:
- Materials Science
- Solid State Chemistry
- Geophysics
Background:
- Binary transition metal molybdates exhibit diverse properties and applications.
- Limited data exists on the high-pressure behavior and phase transition resistance of multiphase molybdates.
Purpose of the Study:
- To investigate the high-pressure structural characteristics and phase transitions of cobalt molybdate (CoMoO4).
- To assess the pressure-induced structural reconstruction and phase transition resistance in thin CoMoO4 samples.
Main Methods:
- Utilized a diamond anvil cell for high-pressure generation.
- Employed in situ laboratory Raman spectroscopy and X-ray diffraction (XRD).
- Conducted synchrotron radiation X-ray diffraction for detailed structural analysis up to 28 GPa.
Main Results:
- β-CoMoO4 underwent two gradual phase transitions up to 28 GPa.
- An initial transition to the α-phase occurred around 1 GPa.
- A high-pressure phase (HP-phase) emerged around 12 GPa, becoming dominant by 17-18 GPa with hysteresis.
- Thin samples showed enhanced structural resistance compared to previous studies.
- Upon pressure release, CoMoO4 largely reverted to the β-phase, retaining a trace of the HP-phase.
Conclusions:
- Elucidated the two-stage phase transitions and pressure-induced structural reconstruction of thin CoMoO4.
- Demonstrated enhanced structural resistance in thin CoMoO4 samples under high pressure.
- Contributed to the fundamental understanding of binary transition metal molybdates under extreme conditions.
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