The Influence of Defects on the Luminescence of Trivalent Terbiumin Nanocrystalline Yttrium Orthovanadate

Author(s)

Perrella, Rafael Vieira ; Walker, Marc ; Chamberlain, Thomas W. ; Walton, Richard, I ; de Sousa Filho, Paulo Cesar

• Document type: Journal article
• Source: Nano Letters; v. 22, n. 9, p. 7-pg., 2022-05-11.

Abstract

Terbium-doped YVO4has been considered anonluminescent solid since thefirst classic studies on rare-earth-doped phosphors in the 1960s. However, we demonstrate thatdefect engineering of YVO4:Tb3+nanoparticles overcomes themetal-metal charge transfer (MMCT) process which is respon-sible for the quenching of the Tb3+luminescence. Tetragonal(Y1-xTbx)VO4nanoparticles obtained by colloidal precipitationshowed expanded unit cells, high defect densities, and intimatelymixed carbonates and hydroxides, which contribute to a shift of theMMCT states to higher energies. Consequently, we demonstrateunambiguously for thefirst time that Tb3+luminescence can beexcited by VO43--> Tb3+energy transfer and by direct populationof the5D4state in YVO4. We also discuss how thermal treatmentremoves these effects and shifts the quenching MMCT state tolower energies, thus highlighting the major consequences of defect density and microstructure in nanosized phosphors. Therefore,ourfindings ultimately show nanostructured YVO4:Tb3+can be reclassified as a UV-excitable luminescent material (AU)

• FAPESP's process: 20/10518-0 - Inorganic nanoparticles as new optical tools for nanoscale sensing
• Grantee: Paulo Cesar de Sousa Filho
• Support Opportunities: Regular Research Grants
• FAPESP's process: 17/19909-0 - Multimodal luminescent nanoparticles for thermometry and oxygen reactive species sensing
• Grantee: Rafael Vieira Perrella
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 18/08334-9 - New advanced materials for sensing applications: a collaborative project on structural and spectroscopic characterisation of novel rare-earth solids
• Grantee: Paulo Cesar de Sousa Filho
• Support Opportunities: Regular Research Grants