Photoluminescence properties of aeschynite‐type LaNbTiO₆:RE³⁺ (RE = Tb, Dy, Ho) down‐converting phosphors

Abstract

In this study, a series of LaNbTiO6:RE(3+) (RE = Tb, Dy, Ho) down-converting phosphors were synthesized using a modified sol-gel combustion method, and their photoluminescence (PL) properties were investigated as a function of activator concentration and annealing temperature. The resultant particles were characterized using X-ray diffraction, transmission electron microscopy, scanning electron microscopy, UV/Vis diffuse reflectance spectroscopy and PL spectra. The highly crystalline LaNbTiO6:RE(3+) (RE = Tb, Dy, Ho) phosphors with an average size of 200-300 nm obtained at 1100°C have an orthorhombic aeschynite-type structure and exhibit the highest luminescent intensity in our study range. The emission spectra of LaNbTiO6:RE(3+) (RE = Tb, Dy, Ho) phosphors under excitations at UV/blue sources are mainly composed of characteristic peaks arising from the f-f transitions of RE(3+), including 489 nm ((5) D4 → (7) F6) and 545 nm ((5) D4 → (7) F5) for Tb(3+), 476 and 482 nm ((4) F9/2 → (6) H15/2) and 571 nm ((4) F9/2 → (6) H13/2) for Dy(3+), and 545 nm ((5) F4 + (5) S2 → (5) I8) for Ho(3+), respectively. The luminescent mechanisms were further investigated. It can be expected that these phosphors are of intense interest and potential importance for many optical applications.

A Novel Scheme to Obtain Y2O2S:Er3+ Upconversion Luminescent Hollow Nanofibers via Precursor Templating

“…(5) Formation Mechanism for Y 2 O 2 S:Er 3+ Hollow Nanofibers Figure 9 shows the formation mechanism of Y 2 O 2 S:Er 3+ hollow nanofibers. PVP, Y(NO 3 ) 3 crystallites, many crystallites were combined into nanoparticles, then some nanoparticles were mutually connected to generate hollow-centered Y 2…”

“…I N the past a few years, as a kind of important optical functional materials, rare-earth ions (RE 3+ ) doped upconversion luminescent materials 1 have received extensive researches due to their peculiar 4f electron configuration and unique properties, 2,3 and wide applications in many fields such as solar cell, 4,5 infrared detection, 6 labeling, 7 and bioimaging. 8 Y 2 O 2 S is one of the most important matrixes for lanthanide-doped phosphors, 9 providing a wide band gap (4.6-4.8 eV) 10 and suitable Y 3+ sites where Y 3+ can be easily substituted by other trivalent rare-earth ions without additional charge compensation.…”

“…, and Er(NO 3 )3 were mixed with DMF to form spinning solution. Y 3+ , Er 3+ , and NO 3 À were mixed or absorbed onto PVP to form sol with certain viscosity, and then PVP/[Y(NO 3 ) 3 + Er(NO 3 ) 3 ] composite nanofibers were fabricated via electrospinning of the spinning solution.…”

Enhanced orange–red emission of SrZn2(PO4)2:Sm3+ via codoping Eu2+ as a sensitizer

“…In recent years, one of the key factors limiting the progress of white light‐emitting diodes (LEDs) has been a general lack of red‐emitting phosphors that can improve the performance of white light blends in terms of color rendering and lumen equivalency . Taking into account Sm 3+ 4 G 5/2 – 6 H J emission in the red region, the development of Sm 3+ ‐activated samples is of interest because such phosphors are expected to possess superior red color purity .…”

Mechanistic investigation on up and down conversion of Er3+ and Gd3+ co-doped YTiNbO6 phosphors

“…16,17 What is more, our previous work has demonstrated that RETiNbO 6 (RE ¼ Y, La) doped with Eu 3+ , Er 3+ , Dy 3+ and Ho 3+ has great down-conversion (DC) emission as the RE 3+ doped into the YNbTiO 6 host may offer more probability of gaining many multi-stage transition pathways and broadly distributed emission spectra. [18][19][20][21] However, to the best of our knowledge, there are few reports about the UC of YTiNbO 6 . On the one hand, Y 3+ can be easily replaced by RE 3+ , which induced some novel up-conversion luminescence (UCL) phenomena without any charge compensation problems.…”