Photoluminescence properties and structural analysis of Tb³⁺-doped K₃Gd(BO₂)₆: A first study on negative thermal quenching
| dc.contributor.author | Souadi G. | |
| dc.contributor.author | Madkhli A.Y. | |
| dc.contributor.author | Kaynar U.H. | |
| dc.contributor.author | Gok C. | |
| dc.contributor.author | Aydin H. | |
| dc.contributor.author | Coban M.B. | |
| dc.contributor.author | Kaynar S.C. | |
| dc.contributor.author | Ayvacikli M. | |
| dc.contributor.author | Can N. | |
| dc.date.accessioned | 2025-04-10T11:01:45Z | |
| dc.date.available | 2025-04-10T11:01:45Z | |
| dc.date.issued | 2025 | |
| dc.description.abstract | In this study, Tb³⁺-doped K₃Gd(BO₂)₆ phosphors were synthesized using the microwave-assisted sol-gel method to explore their photoluminescence (PL) properties and thermal stability. XRD and Rietveld refinement confirmed the incorporation of Tb³⁺ ions, without secondary phases. PL analysis revealed a strong green emission near 542 nm, attributed to the ⁵D₄ → ⁷F₅ transition of Tb³⁺ ions. An optimal Tb³⁺ concentration of 3 wt% was identified, beyond which concentration quenching significantly reduced luminescence intensity. Radiative energy transfer, occurring via reabsorption, was observed at lower concentrations, facilitating efficient energy migration. Conversely, at higher concentrations, non-radiative processes such as cross-relaxation dominated. Remarkably, negative thermal quenching (NTQ) was observed up to 470 K, with an activation energy of 0.96 eV. Additionally, Na⁺ co- doping introduced lattice distortions that enhanced energy transfer between Tb³⁺ ions and improved luminescence efficiency. The chromaticity diagram highlighted a shift towards the yellow-green region with increasing the Tb³⁺ concentration, demonstrating tunable emission properties for solid-state lighting applications. © 2024 Elsevier B.V. | |
| dc.identifier.DOI-ID | 10.1016/j.jallcom.2024.178147 | |
| dc.identifier.uri | http://hdl.handle.net/20.500.14701/43624 | |
| dc.publisher | Elsevier Ltd | |
| dc.title | Photoluminescence properties and structural analysis of Tb³⁺-doped K₃Gd(BO₂)₆: A first study on negative thermal quenching | |
| dc.type | Article |