Novel Emitting‐Color Tunable Phosphors Ba₃Y₂(BO₃)₄:Ce³⁺,Tb³⁺ with Efficient Energy Transfer for Near‐UV Light‐Emitting Diodes

Abstract

This work presents the ultraviolet–visible spectroscopic properties of Ba3Y2(BO3)4:Ce3+,Tb3+ phosphors prepared by a high‐temperature solid‐state reaction. Under ultraviolet light excitation, tunable emission from the blue to yellowish‐green region was obtained by changing the doping concentration of Tb3+ when the content of Ce3+ is fixed. The efficient energy transfer process between Ce3+ and Tb3+ ions was observed and confirmed in terms of corresponding excitation and emission spectra. In addition, the energy transfer mechanism between Ce3+ and Tb3+ was proved to be dipole–dipole interaction in Ba3Y2(BO3)4:Ce3+,Tb3+ phosphor. By utilizing the principle of energy transfer and appropriate tuning of Ce3+/Tb3+ contents, Ba3Y(BO3)4:Ce3+,Tb3+ phosphors can have potential application as an UV‐convertible phosphor for near‐UV excited white light‐emitting diodes.

Multicolor Emission in a Single‐Phase Phosphor Ca3Al2O6:Ce3+,Li+: Luminescence and Site Occupancy

“…As a result, the emission color of Ce 3+ -activated phosphors can be tuned from blue to red, such as blue-emitting Ca 8 La 2 (PO 4 ) 6 O 2 :Ce 3+7 and Ba 3 Y 2 (BO 3 ) 4 :Ce 3+ , 8 green-emitting Ca 3 Sc 2 Si 3 O 12 :Ce 3+ , 9,10 yellow-emitting LaSr 2 AlO 5 :Ce 3+11,12 and c-Ca 2 SiO 4 : Ce 3+ , 13 yellow-orange emitting CaAlSiN 3 :Ce 3+ , 14 red-emitting a-(Y, Gd)FS:Ce 3+ , 15 and so forth. As the 5d orbits of Ce 3+ ions are on the outer shell, the positions of the excitation and emission bands are sensitive to the host lattice, to be precise, the surroundings of the crystalline site for Ce 3+ ions.…”

Luminescence and energy transfer of emission tunable phosphors YBa3B9O18:Ce3+, Tb3+

“…By monitoring Ce 3+ -emission at 388 nm, the excitation spectrum was obtained, in which the broad bands should be assigned to the electronic transitions from the ground state to the different crystal field splitting bands of excited 5d states of Ce 3+ [6,14] Fig. 2(a) can be observed, indicating the efficient ET process between Ce 3+ and Tb 3+ in YBa 3 B 9 O 18 :0.04Ce 3+ , 0.1Tb 3+ exist truly and the Tb 3+ emission can be sensitized greatly by Ce 3+ ions in UV region [1]. Fig.…”

“…Thus, Ce 3+ , Tb 3+ co-activated phosphors can achieve the tunable emission in visible region under UV excitation, which can match well with the UV chips-based w-LEDs [8]. Over the past few years, more and more researchers have focused on the luminescence properties of Ce 3+ , Tb 3+ co-activated inorganic phosphors [1,[8][9][10] In 2004, Li et al [11] first reported a kind of borate compound YBa 3 B 9 O 18 , the structure of which was characterized with a space group of P6 3 /m and was made up of planar B 3 O 6 groups parallel to each other along the (0 0 1) direction, regular REO 6 octahedra and irregular BaO 6 and BaO 9 polyhedra to form an analog structure of ␤-BaB 2 O 4 [11]. Recently, some works have been published on the luminescence properties of rare earth ion doped with YBa 3 B 9 O 18 [12,13].…”

“…Many researchers have paid more and more attention to the sensitizing effect of Ce 3+ ion on Tb 3+ , Eu 2+ , Mn 2+ , and Yb 3+ ions [1][2][3][4]. As a sensitizer, Ce 3+ often shows intense 4f5d absorption band in ultraviolet (UV) region in many oxide hosts and enhance the light yield of the activator through the energy transfer (ET) process from Ce 3+ to activator under UV excitation, which is of great value to improve the luminescence efficiency of phosphors for white light-emitting diodes w-LEDs application.…”

Chemical behavior and spectroscopic properties of rare earth borates in glazes

“…We should also mention here recent investigations on alkali and alkaline earth borate phases (e.g. of compositions NaSr 4 (BO 3 ) 3 , Ba 3 Y 2 (BO 3 ) 4 , NaCaBO 3 ) doped with Ce 3 þ , Tb 3 þ and Mn 2 þ , the latter of which displayed efficiencies of the green emission of 36% under 347 nm excitation [14][15][16]. Due to the still moderate quantum yields and higher energy excitation maxima given for NaCaBO 3 , as well as of the undiluted CeBO 3 :Tb, we decided to focus on borate compositions comprising Y 3 þ , Ce 3 þ and Tb 3 þ .…”