near-UV Light Excitation Research Articles

Quenching mechanism and luminescence enhancement strategy of Eu2+-activator in fluoroborate host Ba5B4O10F2

Fluoroborates have garnered significant research interest due to their intricate structure and unique nonlinear optical properties. In this work, pure and Eu-activated Ba5B4O10F2 were prepared via the high-temperature solid-state ceramic method. Ba5B4O10F2 is a wide band semiconductor (Eg = 4.51 eV) with an indirect transition characteristic. The optical absorption, photoluminescence, and dynamic spectra of Eu2+/3+ activators were investigated. Luminescence intensities of Eu2+ and Eu3+ had distinctly different responses to doping content. The residual Eu3+ centers in Ba5-5xEu5xB4O10F2 (x > 0.03) cannot be avoided even it was sintered in a reducing atmosphere. Time-resolved spectra and decay curves also confirm the presence of Eu3+ with Eu2+. Under near-UV light excitation, a strong emission band from the 5d→4f transition of Eu2+ was detected overlapping with sharp peaks from (5D0→7F0,1,2,3,4) of Eu3+ in Ba5-5xEu5xB4O10F2 (x > 0.03). As the Eu-doping level increases, the intensity ratio of Eu2+ and Eu3+ changes regularly, and the luminescent intensity of Eu3+ obviously and systematically becomes stronger. As the temperature changes from 25 °C to 150 °C, the luminescent intensity of Eu3+ increases, while that of Eu2+ gradually decreases. The results confirm the energy transfer (ET) from Eu2+ to Eu3+ in Ba5B4O10F2. Eu3+ can act as killers, leading to the luminescence quenching of Eu2+ activators. The heterovalent substitution of Eu and NaF in Ba5B4O10F2 not only reduces the content of Eu3+ but also significantly enhances the efficiency of Eu2+. The experiments demonstrate that to improve the luminescence efficiency of Eu2+, it is important to focus on reducing the residual Eu3+ in the lattice through enhancing the reduction from Eu3+ to Eu2+.

A new rare-earth orthoborate Ba2CdSm2(BO3)4: Synthesis, crystal structure, vibrational spectra, and luminescent properties

A new rare-earth orthoborate Ba2CdSm2(BO3)4 was prepared using the high temperature molten salt method and structurally characterized by single-crystal XRD analysis with following crystallographic data: Pna21, a ​= ​7.6621(1) Å, b ​= ​26.2866(4) Å, c ​= ​16.4563(3) Å, V ​= ​3314.47(9) Å3, and Z ​= ​12. It exhibits a complicated three-dimensional framework constructed from (Cd/Sm)On (n ​= ​7, 8, and 9) distorted polyhedra and BO3 planar triangles, with the open channels and the pockets on the wall of the channels hosting Ba2+ and Ba2+/Sm3+ cations. In addition, the phase purity, morphology, IR, Raman, XPS, UV–vis absorption spectra and luminescent properties of this compound were studied. Upon excitation at 401 ​nm, Ba2CdSm2(BO3)4 displays the orange-red emission with CIE coordinates of (0.5869, 0.4122), which is associated with the characteristic transitions from the excited state 4G5/2 to the ground state 6HJ (J ​= ​5/2, 7/2, 9/2, 11/2) of Sm3+ ion. The phosphor shows the stable luminescence at elevated temperature, and its room temperature fluorescent decay profile exhibits a biexponential shape with the average lifetime of 0.7297 ​ms. As it is expected, Ba2CdSm2(BO3)4 may be a potential orange-red phosphor under near-UV light excitation.

Effects of Eu3+ doping on the luminescence properties of novel Sr2CaLa(VO4)3 from partial substitution of Sr2+ by Ca2+ in Sr3La(VO4)3

Eu 3+ -activated Sr 3 −x Ca x La(VO 4 ) 3 phosphors were fabricated via citric-acid-assisted sol combustion. Characterization of the Sr 3 −x Ca x La(VO 4 ) 3 :Eu 3+ samples with different concentrations of Ca 2+ revealed a hexagonal crystal structure belonging to the R -3 m space group. The amount of Ca 2+ added ( x ) was controlled within 0 ≤ x ≤ 2 to yield high-purity phosphors. Scanning electron microscopy results showed that an increase in Ca 2+ concentration resulted in a decrease in the particle size of Sr 3 −x Ca x La(VO 4 ) 3 :Eu 3+ , with the shape gradually changing from nearly equiaxed to lath-shaped. The Sr 2 CaLa(VO 4 ) 3 :Eu 3+ phosphor (denoted as SCLVO:Eu 3+ ) exhibited the strongest photoluminescence (PL) intensity at 618 nm among the samples under excitation of 394-nm near-UV (NUV) light. The study of Eu 3+ doping concentration confirmed that Eu 3+ could enter the lattice of the SCLVO matrix without altering its crystal structure. SCLVO:Eu 3+ was found to strongly absorb 394 nm NUV light and 464 nm blue light. The optimal concentration of the Eu 3+ dopant in the SCLVO host was 0.11, which resulted in the phosphor achieving an excellent PL intensity and a color purity of 98.68%. Tunable luminescence from the orange area (0.5280, 0.4522) of Commission Internationale de l'éclairage (CIE) to the red area (0.6313, 0.3650) was achieved by adjusting the concentration of Eu 3+ . Under 394 nm excitation, SCLVO:0.11Eu 3+ phosphor has a quantum yield (QY) of 28.2% and excellent thermal stability with 0.383 eV activation energy. Consequently, White-light-emitting diode (WLED) based on SCLVO:0.11Eu 3+ phosphor yielded a high color rendering index (CRI), low correlated color temperature (CCT), and CIE coordinates of 91.8, 5196 K, and (0.3407, 0.3612), respectively, under the 20 mA driven current. These results indicated the tremendous potential of SCLVO:0.11Eu 3+ phosphors for application in WLEDs excited by NUV or blue light.

Tuning Emission from Greenish to Blue via Chemical Composition Modulation in Solid Solutions (Sr1–yCay)2Sb2O7:Bi3+ under near-UV Light Excitation

Tuning Emission from Greenish to Blue via Chemical Composition Modulation in Solid Solutions (Sr_1–<i>y</i>Ca_<i>y</i>)₂Sb₂O₇:Bi³⁺ under near-UV Light Excitation

New red phosphor Na3EuB8O15 with an open-window tubular structure.

A new rare-earth polyborate, trisodium europium octaborate, Na3EuB8O15, was prepared using the high-temperature molten-salt method and structurally determined by single-crystal X-ray diffraction analysis. It crystallizes in the triclinic space group P-1 and contains a one-dimensional [B8O15]∞ tube structure that is constructed from BO3 and BO4 polyhedra. The Eu3+ and Na+ cations reside in this structure to ensure cohesion and neutrality. The excitation spectra, emission spectra, decay time and Commission Internationale de l'Éclairage (CIE) chromaticity index of Na3EuB8O15 were studied. Under near-UV light excitation (393 nm), the polyborate shows an intense red emission, which mainly originates from the highest intensities of the 5D0→7F1 and 5D0→7F2 transitions.

Near-UV-excited photoluminescence of terbium (Ⅲ)-activated lithium sodium borophosphate phosphor

At present, borophosphate-based fluorescent powder with doped rare earth activators becomes a hot issue in lighting and display industry. Series of Tb3+-activated Li2NaBP2O8 (LNBP) products were constructed via a solid state reaction procedure. The absorption behavior, dopant Tb3+ concentration- and temperature-dependent photoluminescence, and colorimetric properties have been studied in depth. The photoluminescence optimization is as follows: Upon the excitation of near-UV light, the LNBP:Tb3+ product can produce strong visible light with a dominant peak at 544 nm because of the intrinsic 4f optical transitions of Tb3+, and tuning dopant Tb3+ concentration results in the variation of the emitting light color from white to yellowish-green to yellow-green. The LNBP:0.03Tb3+ phosphor possesses the maximal photoluminescence intensity. The finding indicates that the title product with good thermal stability is a promising phosphor for solid state light applications.

Cation substitution and luminescence properties of Eu2+/Ga3+-codoped Na2ZrSi2O7

Eu2+/Ga3+ co-doped Na2ZrSi2O7 phosphors were prepared via a facile solid-state reaction route. The structural characteristics, photoluminescence spectra, and application performances of Na2-x Eu x Zr1-x Ga x Si2O7 (x= 0, 0.02, 0.04, 0.06, 0.08, 0.10) were investigated. The main motivation of Ga3+ co-doping on Zr4+ is to eliminate the charge imbalance created by the aliovalent substitution of Eu2+ on Na+ sites in the lattices. The results indicated that the Eu2+/Ga3+ co-doped Na2ZrSi2O7 kept a good esseneite-like structure with a triclinic space group of P-1. The phosphor presents a narrow cyan-emitting band centered at 485 nm under near-UV light excitation. The luminescence efficiency of Eu2+ activator was significantly improved through the co-doping of Ga3+ for Zr4+ ions in Na2ZrSi2O7. The maximum luminescence absolute quantum efficiency of 43% was observed in Na2-x Eu x Zr1-x Ga x Si2O7 (x = 0.1) under the excitation of the near-UV light. The phosphor has good thermal stability with an activation energy of 0.31 eV. To realize charge compensation via cation co-substitution could be a practical strategy to improve luminescence in Eu2+-activated phosphors on aliovalent sites.

Synthesis and characterization of near UV excitable Y2O2S:Eu3+ entrapped ZnO for white light emitting diode applications

Near UV excitable, white light emitting Y2O2S:Eu3+ entrapped ZnO has been prepared by sol-gel combustion method from zinc acetate, urea and Y2O2S:Eu red phosphor. In order to study the generation of white light, red phosphor has been entrapped in ZnO in various weight ratios (90:10, 50:50, 70:30). At the excitation of near UV light at 375 ​nm, this phosphor entrapped ZnO composite shows an white light emission, and it also comprises bluish green and red light emission in the wide range of wavelength starting from 420 to 650 ​nm, originated from the ZnO and Y2O2S:Eu3+, respectively. A highest photo-luminescent intensity with white light could be obtained for Y2O2S:Eu3+ and ZnO in the weight ratio of 70:30.The obtained light shows a warm white light with a CRI of 75 and color co-ordinates of (x ​= ​0.44, y ​= ​0.35). This phosphor composite could be useful for white light emitting diode applications.

Broad-Band Excited and Tunable Luminescence of CaTbAl3O7:RE3+ (RE3+ = Ce3+ and/or Eu3+) Nanocrystalline Phosphors for Near-UV WLEDs.

Here, we demonstrate a novel donor-intermediate-receptor energy transfer model through a Ce3+ → Tb3+ → Eu3+ scheme in a CaTbAl3O7:Ce3+,Eu3+ nanocrystalline phosphor. A new type of CaTbAl3O7 and CaTbAl3O7:RE3+ (RE3+ = Ce3+ and/or Eu3+) nanocrystalline phosphors were prepared by a simple sol-gel method. There exist efficient energy transfers of Ce3+ → Tb3+, Tb3+ → Eu3+, and Ce3+ → Tb3+ → Eu3+ in CaTbAl3O7:RE 3+ (RE 3+ = Ce3+ and/or Eu3+) nanocrystalline phosphors. With near-UV or UV light excitation, the as-prepared CaTbAl3O7:RE 3+ (RE 3+ = Ce3+ and/or Eu3+) nanocrystalline phosphors' luminous color can be regulated from green to green-yellow, yellow, orange, and orange-red by adjusting the doping concentration, categories, and different proportions of codoping Ce3+ to Eu3+ ions in the CaTbAl3O7 matrix. The luminescence mechanism with respect to the CaTbAl3O7:RE3+ (RE3+ = Ce3+ and/or Eu3+) nanocrystalline phosphors has been tentatively proposed. Due to their excellent luminescence properties, the as-prepared CaTbAl3O7, CaTbAl3O7:Ce3+, CaTbAl3O7:Eu3+, and CaTbAl3O7:Ce3+,Eu3+ nanocrystalline phosphors exhibit bright prospects in NUV-LEDs and other photoelectric field.

Synthesis of G-La2Si2O7:Eu2+ phosphors by addition of AlF3: Experimental and theoretical analysis

The Eu2+-doped G-La2Si2O7 phosphor was successfully prepared through the high-temperature solid-state reaction method with the aid of AlF3 flux. The results of Eu L3-edge XANES characterization showed that only Eu3+ can be detected in as-received G-La2Si2O7 phosphor and that Al2O3 addition leads to a partial reduction of Eu3+ to Eu2+, while complete reduction occurs with AlF3 addition. The obtained Eu2+-doped G-La2Si2O7 phosphor exhibited typical Eu2+ blue-green emission under the near-UV light excitation. The analysis of Fourier transform infrared spectroscopy (FT-IR) and 27Al nuclear magnetic resonance (NMR) results suggests that Al occupies the Si sites and F occupies the O sites. The positive influence of Al–F doping is related to the structure of the produced phosphors, which was analyzed with the aid of first-principles density functional calculations. The results of the theoretical calculations are a good match to the experimental findings.

Design and realization of an orange–red phosphor samarium-activated diphosphate Na5Bi1−xSmx(P2O7)2

Recently, rare-earth-activated phosphors have been excessively studied for applications in field of white light-emitting diodes (W-LEDs). In this work, a series of Sm3+-doped Na5Bi(P2O7)2 phosphors have been synthesized via traditional high-temperature solid-state reaction method. The purity and phase structure were verified by powder X-ray diffraction (XRD) analysis. Owing to the 4G5/2→6H7/2 transition of Sm3+, Na5Bi1−xSmx(P2O7)2 phosphors show intense orange–red emission centered at 600 nm under near-UV light (403 nm) excitation. The 4% Sm3+ ion is the optimum doping concentration. The concentration quenching dominant mechanism is the d−d interaction. Moreover, phosphors Na5Bi0.96Sm0.04(P2O7)2 show good thermal stability, restraining 79.4% at 150 °C of that measured at 25 °C. The CIE coordinates of phosphor Na5Bi0.96Sm0.04(P2O7)2 were calculated to be (0.573, 0.414). Therefore, phosphor Na5Bi1−xSmx(P2O7)2 could be potentially used as an orange–red phosphor for W-LEDs.

Tunable photoluminescence and energy transfer of novel phosphor Sr9La2W4O24:Sm3+, Eu3+ for near-UV white LEDs

Novel Sr9La2W4O24:xSm3+ and Sr9La2W4O24:0.15Sm3+, yEu3+ orange-red phosphors with double perovskite tungsten structure are synthesized by high-temperature solid-phase reaction method. X-ray diffraction patterns indicate the prepared phosphors are pure phase with a tetragonal structure and the SEM image displays the long string structure with a diameter of one micron. Under the excitation of near-UV light, the Sm3+ and Eu3+ ions activated Sr9La2W4O24 phosphors exhibit their characteristic emissions in the orange-red region, and the emitting light color of the Sr9La2W4O24:0.15Sm3+, yEu3+ phosphors can be adjusted from orange to red by increasing the concentration of Eu3+ ions implying their potential applications as orange-red emitting phosphor for LED in solid-state lighting. The optimal doping concentration of Sm3+ ions in Sr9La2W4O24:xSm3+ phosphors is around 15 mol%. The energy transfer from Sm3+ to Eu3+ is discussed and the major mechanism for concentration quenching is the dipole–dipole (d–d) interaction.

Realizing near-UV light excitation of Mn2+ via efficient energy transfer from Eu2+ for white LEDs

A series of Eu2+ and Mn2+ co-activated Al5O6N multi-color phosphors were fabricated through the gas-pressure sintering method, and they displayed intense blue-green emitting at near-ultraviolet irradiation due to efficient energy transfer. Dipole-dipole interaction was proved to be the leading role for Eu2+-Mn2+energy transfer and the highest energy transfer efficiency was obtained about 78 %. Furthermore, tunable emissions from blue to green were observed through regulating the concentration of Eu2+ and Mn2+. In addition, the temperature-dependent luminescence behavior of Al5O6N:Eu2+, Mn2+ was examined, and the emission intensity at 150℃ maintains 82 % of initial intensity, which indicates superior thermal stability. These outcomes illustrate that the Al5O6N: Eu2+, Mn2+ phosphors may be potentially used in white LEDs.

Mn4+ doped tetratungstate Sr9Gd2W4O24 far-red phosphor: Synthesis, luminescence properties, and potential applications in indoor plant cultivation

The red oxide phosphors activated by Mn4+ have become a research hotspot because of their excellent physical/chemical stability, which can be applied in the field of light-emitting diodes (LED) plant growth lighting. Here, a new type of Sr9Gd2W4O24 (SGWO):Mn4+ red phosphor was prepared by traditional high temperature solid state reaction method. The phase compositions and morphologies of powders were analyzed by X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). The luminescent properties of the samples with varying Mn4+ concentrations were investigated, and the photoluminescence excitation (PLE) spectra illustrate that samples can be effectively excited by near-ultraviolet/blue light. Furthermore, typical concentration quenching occurs when the doping concentration of Mn4+ exceeds 0.4 mol%. In addition, the thermal activation energy of the sample was calculated to be 0.3641 eV. Importantly, under the excitation of near-UV light at 365 nm, SGWO:0.004Mn4+ phosphor can emit bright far-red light. All the results indicated that SGWO:Mn4+ phosphors have potential application value in indoor plant cultivation.

Synthesis of intense red light-emitting β-Ca2SiO4:Eu3+ phosphors for near UV-excited light-emitting diodes utilizing agro-food waste materials

The sugarcane baggage ash and chicken shells are the abundant by-products of agro-food waste materials. These waste materials have hazardous impact on environment and thus require proper utilization to get valuable products. The present report is a detailed study to use these materials to fabricate intense red light-emitting Eu-doped Ca2SiO4 (C2S) phosphors via conventional solid-state method. For this purpose, silica (SiO2) is extracted from sugarcane baggage ash at 600 °C via alkali extraction followed by acid precipitation method. The raw eggshells were washed, dried, and calcined in furnace at 900 °C in order to get calcium oxide (CaO). The structural, morphological, elemental, optical, and luminescent properties were characterized via X-ray diffraction, scanning electron microscopy, energy dispersed X-ray spectroscopy, transmission electron microscopy, UV–Visible spectroscopy, Fourier transform infrared spectroscopy, and photoluminescence techniques. The effect of Eu concentration (0.1 to 0.5 mol%) on the structural, optical, and luminescent properties of Ca2SiO4 has been studied in detail. The agro-food waste-derived phosphors exhibited intense emission at 625 nm corresponding to 5D0 → 7F2 transitions of Eu3+ ions under near-UV light excitation at 393 nm. The quenching mechanism and type of energy transfer interactions involved are studied via Blasse and Dexter’s theory. The photometric parameters such as CIE coordinates, CCT values, and color purity are calculated from emission spectra. Judd–Ofelt (Ω2, Ω4) and other spectral parameters (radiative rates, branching ratio, radiative lifetime, and radiative cross-sectional area) are calculated as a probe to investigate the luminescent environment of Eu3+ ions in the Ca2SiO4 host lattice. The present agro-food waste-derived phosphors are expected to be promising candidates for UV-excited white light-emitting diodes in solid-state lightning and optoelectronic devices.

Phase-formation and luminescence properties of Eu3+-doped Bi2O3 on synthetic process

This work developed a new method to modify the phase formation, morphological characteristics and photoenergy conversion of Eu3+-doped bismuth oxides via solvothermal preparation and post-annealing treatments. As-prepared products are the tetragonal-structured Bi/t-Bi2O2.75:Eu3+ nanocomposites via introducing metallic Bi0 by in-situ reduction, which showed a ball-like profile (100 nm). After the post-annealing treatments, as-prepared Bi/t-Bi2O2.75:Eu3+ developed into cubic phase crystals of Eu3+-stabilized δ-Bi2O3 (δ-Bi2O3:Eu3+), which had a plate-like shape with the length and width of 1–2 μm. The dark colored Bi/t-Bi2O2.75:Eu3+ shows a very broad absorption band from UV to 735 nm. The post-annealed δ-Bi2O3:Eu3+ shows a yellow nature color and an abrupt cut-off of absorption edge around 570 nm. The investigations focused on different photo-energy conversion modes of two samples, i.e., photoluminescence and photocatalysis. The photo-degradation abilities on RhB solutions were evaluated with the excitation of visible light. As-prepared Bi/t-Bi2O2.75:Eu3+ showed much more excellent photocatalytic behaviors than the post-annealed δ-Bi2O3:Eu3+. Compared with pure δ-Bi2O3, δ-Bi2O3:Eu3+ has comparable photocatalytic ability. The post-annealed δ-Bi2O3:Eu3+ shows very efficient red-luminescence with preferable excitation of near UV-light. The photo-energy conversion mechanisms were proposed to discuss the luminescence properties, decay lifetimes and multivalent ions. Eu3+-doped Bi2O3 could be a good candidate with multimodal photo-energy conversion applications, i.e., photocatalyst and phosphor, depending on the reductant in the synthesis and post-annealing treatment.

K3Eu5(PO4)6: hydrothermal synthesis, crystal structure and photoluminescence properties.

An anhydrous orthophosphate, K3Eu5(PO4)6 (tripotassium pentaeuropium hexaphosphate), has been prepared by a high-temperature solid-state reaction combined with hydrothermal synthesis, and its crystal structure was determined by single-crystal X-ray diffraction analysis (SC-XRD). The results show that the compound crystallizes in the monoclinic space group C2/c and the structure features a three-dimensional framework of [Eu5(PO4)6]∞, with the tunnel filled by K+ ions. The IR spectrum, UV-Vis spectrum and luminescence properties of polycrystalline samples of K3Eu5(PO4)6, annealed at temperatures of 650, 700, 750, 800 and 850 °C, were investigated. Although with a full Eu3+ concentration (9.96× 1021 ions cm-3), the self-activated phosphor K3Eu5(PO4)6 shows s strong luminescence emission intensity with a quantum yield of 37%. Under near-UV light excitation (393 nm), the series of samples shows the characteristic emissions of Eu3+ ions in the visible region from 575 to 715 nm. The sample sintered at 800 °C gives the strongest emission and its lifetime sintered at 800 °C (1.88 ms) is also the longest of all.

Single Crystal Growth and Crystal Structure Analysis of Novel Orange-Red Emission Pure Nitride CaAl2Si4N8:Eu2+ Phosphor.

Single crystal of novel orange-red emission CaAl2Si4N8:Eu2+ phosphor was grown by our original vapor phase technique, and the precise crystal structure was investigated for the first time by single crystal X-ray diffraction analysis. The crystal structure of CaAl2Si4N8:Eu2+ single crystal was verified to be an α-Si3N4-type trigonal structure (space group P31c) with a = 0.79525(9) nm, c = 0.57712(8) nm, and z = 2. The Ca atoms were coordinated to seven nitrogen atoms and located in the three-dimensional framework formed by (Al, Si)N4 tetrahedra. The single-crystal CaAl2Si4N8:Eu2+ phosphors exhibited a broad reddish-yellow emission with a peak at 600 nm under near-UV and blue light excitation. When increasing the temperature up to 150 °C, the emission intensity of the CaAl2Si4N8:Eu2+ phosphor decreased to 88% of the initial value at 25 °C.

Optimized photoluminescence and electronic properties of europium doped phosphate red phosphor

Abstract The exploration of red inorganic phosphor component with excellent performance for the development of the display domain is a scientific focus in recent years. In this work, NaAlP2O7:xEu3+ (x = 0, 1, 3, 5, 7, 9, 11, 13%) phosphors have been synthesized using a facile solid-state reaction method. In the solid solution, Eu3+ ion successfully replaces Na+ ion in NaAlP2O7 host. To determine absorption properties of pure and Eu3+ doped NaAlP2O7, theoretical computations and diffuse reflectance absorption measurements have been implemented. Photoluminescence spectra show the red light emission under the broad irradiation wavelength region from near-UV to visible light. Under near-UV light (395 nm) excitation, it exhibits a strong red light emission peaking at 612 nm (5D0 → 7F2 of Eu3+). The emission intensity reaches maximum at doping level of 9 mol% Eu3+, and the concentration quenching mechanism have been discussed in detail. For NaAlP2O7:9%Eu3+, the color purity of the red light is as high as 90%, and the internal quantum efficiency is 35.8%. The performances mean that NaAlP2O7:Eu3+ materials may be potentially applied as red phosphor for near-UV white LEDs.

Strong f-f Excitation and Bright Red Emission in Cd4 Gd1-x Eux O(BO3 )3 (0≤x≤1): Near-UV LED Pumped Red Phosphor with Low Thermal Quenching.

Searching efficient red phosphors under near-UV or blue light excitation is practically important to improve the current white light-emitting diodes (WLEDs). Eu2+ - and Mn4+ -based red phosphors have been extensively studied. Here we proposed that Eu3+ is also a promising activator when it resides on a noncentrosymmetric coordination site. We proved that Cd4 GdO(BO3 )3 is a good host, which has a significantly distorted coordination for Eu3+ . A careful crystallographic study was performed on the solid solutions of Cd4 Gd1-x Eux O(BO3 )3 (0≤x≤1) by Rietveld refinements. The as-doped Eu3+ cations locate at the Gd3+ site and are well separated by CdO8 , CdO6 and BO3 groups; thus, only a slight concentration quenching was observed at ≈80 atom % Eu3+ . Most importantly, the parity-forbidden law of 4f-4f transitions for Eu3+ are severely depressed, thus the absorptions at ≈393 and ≈465 nm are remarkable. Cd4 Gd0.2 Eu0.8 O(BO3 )3 can be pumped by a 395 nm LED chip to give a bright red emission, and when mixed with other commercial blue and green phosphors, it can emit the proper white light (0.3657, 0.3613) with a suitable Ra ≈87 and correlated colour temperature ≈4326 K. In-situ photoluminescence study indicated the low thermal quenching of these borate phosphors, especially under 465 nm excitation. Our case proves the practicability to develop near-UV excited red phosphors in rare-earth-containing borates.