Pressure induced structural transition and optoelectronic modification in inorganic metavanadate phosphor

Area of Science:

• Solid-state chemistry
• Materials science
• Luminescence

Background:

• Alkali metal AVO3 metavanadates are promising inorganic phosphors for white-light emission.
• Their luminescence originates from self-activated broadband emission due to charge transfer in VO4 tetrahedra.
• Cesium metavanadate (CsVO3) exhibits particularly high quantum efficiency.

Purpose of the Study:

• Investigate the optical and structural properties of CsVO3 under high pressure.
• Understand the impact of pressure-induced phase transitions on luminescence.
• Explore CsVO3 as a tunable inorganic luminescent material.

Main Methods:

• Crystal structure prediction
• High-pressure X-ray diffraction
• Raman spectroscopy
• Absorption spectra analysis
• First-principles calculations

Main Results:

• A pressure-induced structural transition from orthorhombic to monoclinic phase was identified.
• The transition involves distortion and reorientation of VO4 tetrahedra.
• Emission peak position (542–672 nm) and FWHM (158–194 nm) showed ultrabroad tunability.
• A direct-indirect bandgap transition occurred around 12 GPa, coinciding with the structural phase transition.
• CsVO3 exhibited white-light emission characteristics under pressure.

Conclusions:

• High pressure effectively modulates the structural and optical properties of CsVO3.
• The observed tunability and white-light emission under pressure highlight its potential for advanced luminescent applications.
• This study provides insights into pressure-induced phenomena in metavanadate phosphors.