Synthesis and luminescence tunability studies in new upconverting BaGeTeO6:Yb3+/Ho3+ phosphors

Liu Shengyi, Gao Duan, Wang Li, Song Wenbin, Zhang Zhiliang, Zhu Ying, Xiao P., Gao S., Zhang Qi

For Russian citation (Opticheskii Zhurnal):

Liu S., Gao D., Wang L., Song W., Zhang Z., Zhu Y., Xiao P., Gao S., Zhang Q. Synthesis and luminescence tunability studies in new upconverting BaGeTeO₆:Yb³⁺/Ho³⁺ phosphors [in English] // Opticheskii Zhurnal. 2026. V. 93. № 7. P. 88–100. DOI: 10.17586/1023-5086-2026-93-07-88-100

Liu S., Gao D., Wang L., Song W., Zhang Z., Zhu Y., Xiao P., Gao S., Zhang Q. Synthesis and luminescence tunability studies in new upconverting BaGeTeO₆:Yb³⁺/Ho³⁺ phosphors (Исследования технологии синтеза и характеристик перестраиваемости люминесценции в люминофорах BaGeTeO₆:Yb³⁺/Ho³⁺) [на англ. яз.] // Оптический журнал. 2026. Т. 93. № 7. С. 88–100. DOI: 10.17586/1023-5086-2026-93-07-88-100

For citation (Journal of Optical Technology):

Abstract:

Subject of the study. Luminescent and temperature-sensitive properties of BaGeTeO₆ phosphors doped with Ho³⁺/Yb³⁺. Purpose of the work. Synthesis and experimental study the structural and optical properties of BaGeTeO₆:Ho³⁺/Yb³⁺ phosphors to assess their suitability as environmentally friendly luminescent materials with enhanced optical radiation conversion and as temperature sensors. Method. BaGeTeO₆ phosphors doped with Ho³⁺ and Yb³⁺ ions were obtained by high-temperature solid-phase synthesis. The phosphor composition was controlled by X-ray diffraction on the crystal lattice; the Rietveld refinement was used to obtain structural information. The phosphor composition was monitored by X-ray diffraction on a crystal lattice, with the results processed using the Rietveld method. Main Results. Analysis of the synthesized phosphor revealed the required changes in the unit cell parameters and volume upon doping with Ho³⁺ and Yb³⁺, confirming the substitution of Ho³⁺ and Yb³⁺ ions for Ba²⁺. When excited by 980 nm radiation, the resulting phosphor exhibited enhanced emission with increasing conversion, concentrated at 546 nm, along with weaker emission at 666 and 757 nm, attributed to Ho³⁺ transitions (⁵S₂, ⁵F₅ ® ⁵I₈, ⁵F₅ ® ⁵I₈, ⁵S₂, ⁵F₄ ® ⁵I₇). The optimal doping concentrations were determined: Ho³⁺ — 5 mol % and Yb³⁺ — 30 mol %. The relative sensitivity for temperature measurement was calculated at 0.0072 K^–1. Practical significance. The obtained results confirm the effectiveness of using the studied environmentally friendly phosphors with an increased conversion efficiency. The studied materials could potentially serve as the basis for the development of highly sensitive temperature sensors, expanding their application in promising optical sensing technologies.

Keywords:

lanthanides, up-conversion luminescence, thermal quenching, BaGeTeO6

Acknowledgements:

National Natural Science Foundation of Liaoning Province, China (2025-MS310), National Natural Science Foundation of China (52201065).

OCIS codes: 300.6280

References:

1. Auzel F. Upconversion and anti-Stokes processes with f and d ions in solids // Chem. Rev. 2004. V. 104. № 1. P. 139‒173. DOI: 10.1021/cr020357g

2. Haase M., Schafer H. Upconverting nanoparticles // Angew. Chem. Int. Ed. 2011. V. 50. № 26. P. 5808. DOI: 10.1002/anie.201005159

3. Hou X.R., Zhou S.M., Jia T.T. Effect of Nd concentration on structural and optical properties of Nd transparent ceramic // J. Lumin. 2011. V. 131. P. 1953‒1958. DOI: 10.1016/j.jlumin.2011.03.059

4. Li T., Guo C.F., Yang Y.M. Efficient green up-conversion emission in Yb³⁺/Ho³⁺ co-doped CaIn₂O₄ // Acta Mater. 2013. V. 61. P. 7481‒7487. DOI: 10.1016/j.actamat.2013.08.060

5. Sun J.Y., Xue B., Sun G.C. Yellow upconversion luminescence in Ho³⁺/Yb³⁺ co-doped Gd₂Mo₃O₉ phosphor // J. Rare Earths. 2013. V. 31. № 8. P. 741. DOI: 10.1016/S1002-0721(12)60351-2

6. Singh V., Rai V.K., Haase M. NIR to visible frequency upconversion in Er³⁺ and Yb³⁺ codoped ZrO₂ phosphor // J. Appl. Phys. 2012. V. 113. № 3. P. 747‒753. DOI: 10.1007/s00339-013-7583-9

7. Dong B., Cao B.S., He Y.Y. Temperature sensing and in vivo imaging by molybdenum sensitized visible upconversion luminescence of rare earth oxides // Adv. Mater. 2012. V. 24. P. 1987‒1993. DOI: 10.1002/adma.201200431

8. Zhao D., Xue Y.L., Fan Y.C. A new series of rare-earth borate phosphate family CsNa₂Ln₂(BO₃)(PO₄)₂ (Ln = Ho, Er, Tm, Yb): Tunnel structure, upconversion luminescence and optical thermometry properties // J. Alloys Compd. 2021. V. 866. P. 158801. DOI: 10.1016/j.jallcom.2021.158801

9. Erdem M., Orücü H., Cantürk S.B., et al. Upconversion Yb³⁺/Er³⁺: Gadolinium gallium garnet nanocrystals for white-light emission and optical thermometry // ACS Appl. Nano Mater. 2021. V. 4. P. 7162. DOI: 10.1021/acsanm.1c01140

10. Brites C.D.S., Fiaczyk K., Ramalho J.F.C.B. Widening the temperature range of luminescent thermometers through the intra- and interconfigurational transitions of Pr³⁺ // Adv. Opt. Mater. 2018. V. 6. P. 1701318. DOI: 10.1002/adom.201701318

11. Jlassi I., Mnasri S., Elhouichet H. Concentration dependent spectroscopic behavior of Sm³⁺-doped sodium fluoro-phosphates glasses for orange and reddish-orange light emitting applications // J. Lumin. 2018. V. 199. P. 516–527. DOI: 10.1016/j.jlumin.2018.03.023

12. Yin X.M., Wang H. High color purity red emission of Y₂Ti₂O₇, Er³⁺ under 1550 and 980 nm excitation // J. Lumin. 2017. V. 182. P. 183–188. DOI: 10.1016/j.jlumin.2016.10.032

13. Kolobkova E., Mironov L.Yu., Apanasevich P.A. Cooperative energy transfer as a probe of clustering in Yb³⁺ doped fluoroaluminate glasses // J. Lumin. 2023. V. 257. P. 119755‒119762. DOI: 10.1016/j.jlumin.2023.119755

14. Grzyb T., Balabhadra S. Upconversion luminescence in BaYF₅, BaGdF₅ and BaLuF₅ nanocrystals doped with Yb³⁺/Ho³⁺, Yb³⁺/Er³⁺ or Yb³⁺/Tm³⁺ ions // J. Alloys Compd. 2015. V. 649. P. 606–616. DOI: 10.1016/j.jallcom.2015.07.151

15. Du S., Wang D., Qiang Q. The dual-model up/down-conversion green luminescence of Gd₆O₅F₈: Yb³⁺, Ho³⁺, Li⁺ and its application for temperature sensing // J. Mater. Chem. C. 2016. V. 4. P. 7148‒7155. DOI: 10.1039/C6TC01812B

16. Liu S.Y., Gao D., Wang L. Influence of Tm³⁺ concentration on long afterglow and photostimulated luminescence properties of Eu²⁺-doped Sr₁Al₂Si₂O₈ blue phosphors // Russ. Phys. J. 2023. V. 66. P. 655–665. DOI: 10.1007/s11182-023-02989-y

17. Cao Q., Yu Y., Wang X. Up-conversion luminescence, temperature dependence and ferroelectric properties in Ho³⁺ and Yb³⁺ co-doped Bi₃TiNbO₉ multifunctional ceramics // Ferroelectrics 2015. V. 489. P. 51‒59. DOI: 10.1080/00150193.2015.1071645

18. Jiang Y., Shen R., Li X. Concentration effects on the upconversion luminescence in Ho³⁺/Yb³⁺ co-doped NaGdTiO₄ phosphor // Ceram. Int. 2012. V. 38. P. 5045‒5051. DOI: 10.1016/j.ceramint.2012.03.006

19. Etchart I., Hernández I., Huignard A. Efficient oxide phosphors for light upconversion; green emission from Yb³⁺ and Ho³⁺ co-doped Ln₂BaZnO₅ (Ln = Y, Gd) // J. Mater. Chem. A. 2011. V. 21. P. 1387‒1394. DOI: 10.1039/C0JM01652G

20. Liu Z., Jiang G., Wang R. Temperature and concentration effects on upconversion photoluminescence properties of Ho³⁺ and Yb³⁺ codoped 0.67Pb(Mg_1/3Nb_2/3)O₃–0.33PbTiO₃ multifunctional ceramics // Ceram. Int. 2016. V. 42. P. 11309‒11313. DOI: 10.1016/j.ceramint.2016.04.049