UV LED Research Articles

Facile Synthesis of Highly Emissive All-Inorganic Manganese Bromide Compounds with Perovskite-Related Structures for White LEDs

Lead-free all-inorganic halide materials with different Mn2+-based crystal structures (Cs3MnBr5 and CsMnBr3) were obtained using a convenient synthetic method. Cs3MnBr5 had a bright green emission (522 nm), with a unique single-exponential lifetime (τavg = 236 µs) and a high photoluminescence quantum yield (82 ± 5%). A red emission was observed in the case of the CsMnBr3 structure with a two-exponential fluorescence decay curve, and the lifetime was 1.418 µs (93%) and 18.328 µs (7%), respectively. By a judicious tuning of the synthetic conditions, a mixed phase of Cs3MnBr5/CsMnBr3 was also produced that emitted white light, covering almost the entire visible spectrum. White-light-emitting diodes (WLEDs) with color coordinates (0.4269, 0.4955), a color temperature of (3773 K), and a color rendering index (68) were then fabricated using the as-prepared powder of mixed phases of Cs3MnBr5/CsMnBr3 with a commercial UV LED chip (365 nm).

UV-LEDs combined with persulfate salts as a method to inactivate microalgae in ballast water

The Ballast Water Management Convention (BWMC) establishes limits for viable organisms in discharged ballast water. UV-based ballast water management systems (BMWS) are among the most common, especially those with low pressure (LP) and medium pressure (MP) mercury lamps. An interesting alternative to mercury lamps could be UV LEDs that have been developing over recent years. UVA, UVB, and UVC LEDs have been tested as a method to inactivate microalgae in ballast water. For this study, the diatom Phaeodactylum tricornutum was selected as a target organism. Comparing the D2 (dose required to achieve two log reductions) for P. tricornutum from different UV treatments, it was observed that UVC LEDs were 74.2 % more efficient than UVB LEDs and, compared with previous studies, 48.1 % more efficient than UVC LP mercury lamps. If a five day dark post-treatment was combined with the UV irradiation to avoid photoreactivation, UVC LEDs were 90 % more efficient than UVB LEDs and, compared with previous studies, 36.8 % more efficient than UVC LP mercury lamps. No damage with or without photoreactivation was caused by UVA irradiation with doses up to 4·104 mJ cm−2. The combination of peroxymonosulfate (PMS) with UVA, UVB and UVC LEDs did not significantly increase the inactivation, and the combination of the peroxydisulfate (PDS) with UVC LEDs slightly decreases the inactivation compared with UVC irradiation alone. In conclusion, UVC LEDs were the most efficient for inactivating P. tricornutum, and the combination of PMS and PDS with UV LEDs did not notably improve it.

Survey and Habitat Assessment of King's Hairstreak (Satyrium kingi) in Maryland Coastal Plain Forests

We surveyed for caterpillars and adults of King's Hairstreak, Satyrium kingi (Klots and Clench, 1952), a globally vulnerable species found along the Atlantic Coastal Plain. Surveys were conducted at three study sites with abundant Symplocos tinctoria (L.) L'Hér. (Family: Symplocaceae), the caterpillar host plant. We found caterpillars at only one site using UV LED flashlights and adults at two of the three sites. Mating was not observed, and eggs were not found. We discuss observations of S. kingi adults and caterpillars, management of our study sites, data from habitat assessments, and recommendations for further study of S. kingi.

Zero-thermal-quenching of LiAl5O8: Eu2+, Mn2+ phosphors by energy transfer and defects engineering

The photoluminescence behavior of inorganic phosphors is generally influenced by thermal stability, which determines the luminescence efficiency of the corresponding devices. Here, a series of Eu2+, Mn2+ co-doped LiAl5O8 blue-green-emitting phosphors with thermal robust are successfully fabricated. The concentration-dependent emission spectra and the decay curves of the as-obtained LiAl5O8: Eu2+, Mn2+ samples manifest the occurrence of the energy transfer from Eu2+ to Mn2+ ions via dipole-dipole interaction, and the corresponding emitted colors are gradually modulated from blue to green under the excitation of 310 nm. Moreover, the zero-thermal-quenching luminescence is observed when the operation temperature is up to 423 K, which is attributed to the energy release from the trapping centers to emitting centers (Eu2+ and Mn2+) at high temperature. Furthermore, a warm white light-emitting diodes (WLEDs) device with correlated color temperature of 5061 K, a color rendering index of 80.6 and long-term stability is fabricated by combining UV LED chip (λex = 310 nm), as-obtained LiAl5O8: Eu2+, Mn2+ phosphor, commercially available red phosphor and green phosphor. These results prove the potential application of the as-obtained LiAl5O8: Eu2+, Mn2+ phosphor for UV-pumped WLEDs devices.

An improved design of the fused silica capillary flow cell for absorbance detection in microcolumn liquid chromatography

Efficient absorbance detection of a low-volume chromatography peak is a difficult task. In this work, an improved design of the fused silica capillary flow cell for absorbance detection in microcolumn liquid chromatography is described. The cell was fabricated from 0.15 mm I. D. fused silica capillary and silica optical fibres. Optical fibres were fully integrated into the cell design and enabled a convenient and effective connection of the cell with the light source and light detector (265 nm UV LED and photodiode in this work). Manufactured cells covered the range of physical lengths 3.1–9.9 mm (55–175 nL) and were used without any focusing optics and slits. Baseline noise was typically below 0.05 mAU and the effective optical path determined in the experiments was 83–97% of the cell's physical length. The level of stray (parasitic) light indicated by a 1% deviation from linearity at 1.7 AU was 0.08% only. The proposed cell design was found to be moderately susceptible to the refractive index change (20–35 mAU baseline change in 5–95% (v/v) gradient of acetonitrile or methanol in a mixture with water, G index up to 4 AU·s/RIU). Manufactured cells were finally applied for absorbance detection of components of test the mixture eluted off 0.3 mm I. D. microcolumn. 9.9 mm cell (175 nL) with an effective optical path of 8.9 mm exhibited contribution to the broadening of chromatography peak comparable with commercial 6 mm (80 nL) rectangular flow cell.

Evaluation of disinfection efficacy of single UV-C, and UV-A followed by UV-C LED irradiation on Escherichia coli, B. spizizenii and MS2 bacteriophage, in water

Ultraviolet light-emitting diodes (UV LEDs) have shown ability to inactivate microorganisms and viruses in water. The unique characteristic of the UV-LEDs' diversity in wavelengths ranging from UV-C, UV-B, and UV-A, allows for wavelengths to be combined in different manners for polychromatic irradiation. Previous studies reported no synergy from simultaneous or sequential UV-C and UV-B as well as UV-C or UV-B followed by UV-A irradiation. However, synergy was reported for UV-A followed by UV-C or UV-B irradiation on various microorganisms. Nevertheless, no clear ground has been reached on whether to adopt single UV-C wavelengths or UV-A followed by UV-C LED, irradiation on inactivation of microorganisms and viruses in water. Therefore, this work evaluates the disinfection efficacy of single UV-C as well as UV-A followed by UV-C LED irradiation on Escherichia coli, Bacillus spizizenii spores and MS2 bacteriophage in water. The UV-C wavelengths were represented by 267 and 278 nm UV LEDs, and UV-A by 368 nm UV LEDs. In this study, E. coli was highly susceptible to UV radiation followed by B. spizizenii spores, and lastly MS2. Repair following UV inactivation was only observed in E. coli. The synergistic effect found in both E. coli, and B. spizizenii spores was attributed to the different inactivation mechanisms of the UV-C and UV-A wavelengths. In both single UV-C, and UV-A followed by UV-C LED irradiations, single 267 nm UV-C LED showed higher inactivation efficacy. Meanwhile, single 278 nm UV-C LED showed higher efficacy in terms of suppression of repair, and electrical energy consumption. Using single UV-C LEDs in a water disinfection system cuts down on related extra costs by avoiding combined wavelengths while still attaining better levels of microorganism inactivation, repair suppression and electrical energy consumption. These findings are applicable for the design and implementation of UV LED water disinfection systems.

Aggregation-Induced Emission Poly(meth)acrylates for Photopatterning via Wavelength-Dependent Visible-Light-Regulated Controlled Radical Polymerization in Batch and Flow Conditions.

A robust wavelength-dependent visible-light-regulated reversible-deactivation radical polymerization protocol is first reported for the batch preparation of >20 aggregation-induced emission (AIE)-active polyacrylates and polymethacrylates. The resulting polymers possess narrow molar mass distributions (Đ ≈ 1.09-1.25) and high end-group fidelity at high monomer conversions (mostly >95%). This demonstrated control provides facile access to the in situ generation of complex sequence-defined tetrablock copolymers in one reactor, even while chain extending from less reactive monomers. Polymerizations can be successfully carried out under various irradiation conditions, including using UV, blue, green, and red LED light with more disperse polymers obtained at the longer, less energetic, wavelengths. We observe a red shift and wavelength dependence for the most efficient polymerization using LED illumination in a polymerization reaction. We find that the absorption of the copper(II) complex is not a reliable guide to reaction conditions. Moreover, the reported protocol is readily translated to a flow setup. The prepared AIE-active polymers are demonstrated to exhibit good photopatterning, making them promising materials for applications in advanced optoelectronic devices.

Thickness dependent wavelength selective NIR-UV-visible photoresponse in ZnO nanowires and silicon heterojunction

In this paper, we report ZnO nanowires (NWs) and silicon-based type-II PN heterojunction for UV–Visible–Infrared self-powered photodetection. The as-grown ZnO NWs were highly crystalline and aligned along the c-axis in the [002] direction revealed in the HRTEM and XRD measurements. The Hall measurements revealed the n-type behavior for ZnO and p-type for p-Si with carrier concentrations of 4.09 × 1016 cm−3 and 1.38 × 1017 cm−3, respectively. The depletion widths were estimated to be ∼35 nm and ∼120 nm, respectively for p-Si and n-ZnO NWs. The Ag/n-ZnO NWs/p-Si/Ag PN heterojunction showed large photoresponse, even at zero bias, under the illumination of commercially available UV–Visible–NIR LEDs, thus acting as a self-powered photodetector. It was interesting to observe that the photoresponse was dependent on the growth time and hence the thickness of ZnO NWs thin film. A maximum zero bias responsivity of ∼0.1 A/W at green (515 nm) was observed and was large for the junction with thicker ZnO NWs film (5 h growth), compared with thinner (3 h growth) device under IR (950 nm) LED illumination, however, it was observed otherwise for UV (395 nm) LED. This suggests that tuning the thickness of the ZnO NWs thin film results in the wavelength selective photoresponse, consequently, paving the way towards UV blind IR-visible photodetector based on ZnO NWs. The transient short circuit current (Isc vs t) and open circuit voltage (Voc vs t) properties showed fast and large responses under periodic illumination of all LEDs (UV–Vis–NIR). The response was observed to depend on the intensity of light and the maximum Voc comes out to be ∼102 mV and Isc ∼5.58 μA, under the illumination of a red laser diode.

Tuning the Red Emission to Instigate Intrinsic White-Light Emission in Single-Phase Phosphor with Excellent Color Rendering Index.

There is ever-growing interest to develop intrinsic white light emitting single-phase phosphors that have high CRI, devoid of bluish tinge, ease of synthesis and are scalable. Herein, manipulating vacuum pressure to instigate white light emission in Cu2+ -doped-ZnS phosphors is reported. The detailed X-ray diffraction and electron microscopy confirm the cubic phase of Cu2+ -doped-ZnS phosphor having agglomerated particles (∼130-150 nm). The incorporation of Cu2+ in the ZnS lattice is substantiated by the anti-Stokes shift of Raman peaks and shifting of XRD peaks to higher 2θ values. Upon increasing Cu2+ doping concentration, the resulted decrease in the FWHM of XRD peaks implies shrinkage of the ZnS lattice. Interestingly, by tailoring the excitation wavelength, the stoichiometry of dopant ion, and defect states by varying the vacuum pressure, the optimized ZSC-3 (3% Cu2+ -doped-ZnS) displays the origin of clear blue, green and red emission bands, consequently giving rise to white light emission (CIE values: 0.345:0398). The PLQY and average lifetime calculated for ZSC-3 are 5.98% and 1.5 ms, respectively. Such intense white light emission prompted to fabricate a prototype using a 310 nm UV LED. It exhibits high CRI (97) and warm CCT (4538 K), meeting highly desired values for a white light-emitting phosphor for different lighting and electroluminescence applications.

Can postpolymerization for 3D-printed interim restorations be improved?

Statement of problemPostpolymerization methods influence the properties of 3-dimensionally (3D) printed materials. Nevertheless, it is a time-consuming step that could lead dentists to avoid the chairside use of 3D printing. Information assessing the impact of different postpolymerization workflows on flexural strength and color stability is sparse. PurposeThe purpose of this in vitro study was to analyze the impact of different postpolymerization methods on the flexural strength and color stability of 3D-printed resins used for interim restorations. Material and methodsThree resin materials: CT (Cosmos Temp; Yller Biomaterials), DT (Denture Teeth; Formlabs), and CB (C&B MFH; NextDent) were submitted to 4 methods of postpolymerization: a Form Cure polymerization chamber (FC) (Form Cure; Formlabs), a broadband LED device (Valo Grand; Ultradent Products, Inc) operating at 1000 mW/cm2 for 2 different polymerization times (40 seconds/V40 or 120 seconds/V120), and a custom-made polymerization chamber with a 24 W UV LED Strip (CC). The specimens were assessed for flexural strength using an universal testing machine immediately after polymerization or after 10 000 thermal cycles, and the color stability was evaluated using a spectrophotometer at baseline, after 7 days in dark, dry storage at 37 °C and after 24 hours of artificial aging in water at 60 °C. The data were evaluated using 3-way ANOVA (flexural strength) and 3-way repeated measurements ANOVA (color stability), followed by the Tukey HSD test (α=.05). ResultsFlexural strength showed significant differences for resin, postpolymerization method, time, and for the interaction between all effects. CT showed the highest overall flexural strength, while DT showed the lowest. In general, V120 produced specimens with higher flexural strength. Thermocycling did not reduce flexural strength except for CB polymerized with FC and V120, and DT polymerized with V40. For color stability, significant differences were found for resin, postpolymerized method, time, and for the interaction between all effects. The highest ΔE values were observed for DT polymerized using V40 after artificial aging. The lowest values were observed for the same resin but polymerized using V120 after 7 days in dark, dry storage at 37 °C. ConclusionsPostpolymerization with the broadband LED device for 120 seconds can produce specimens with higher flexural strength values and higher color stability when compared with the other postpolymerization workflows tested in this study.

A comparative study on different types of eco-friendly mosquito traps for surveillance and management

Mosquitoes are the most important among all the arthropod vectors that cause human disease in tropical conditions. In order to reduce the mosquito nuisance and the risk of diseases caused by them, it is essential to reduce the mosquito population. Mosquito traps are very useful devices for the surveillance and management of mosquito vectors. It works on the attraction behavior of insects. An ultraviolet or fluorescent light is fitted into the trap for the attraction of mosquitoes. The attracted mosquitoes are killed by a vacuum created by a small exhaust fan. The system does not involve any hazardous chemicals and is perfectly eco-friendly; however, its use has been neglected in India. In the present study, four different types of mosquito traps were procured from online marketing. All the mosquito traps were placed in the animal house of school of studies in zoology, Jiwaji University, Gwalior. Out of total insects trapped, the percentage of mosquitoes was 68 % in the terminator-I, 84% in the terminator-II, 70% in mozziquite, and 38% in the UV LED light-based trap within 6 months. According to device specification and insect trapping, the terminator-II (All Iinn mosquito trap) was found to be comparatively more effective for surveillance and control of mosquitoes.

Ultraviolet Radiation Promoted Hypoxia-Induced Apoptosis in HL-60 Human Promyelocytic Leukemia Cell Line.

Minimal residual disease (MRD) is an important reason for the failure of autologous hematopoietic stem cell transplantation (auto-HSCT). Reducing MRD in grafts is particularly important to improve the efficacy of auto-HSCT. Previously, we reported that ultraviolet light-emitting diode (UV LED) suppressed the expression of Bcl-2 to induce apoptosis in HL-60 cells. Leukemia can lead to severe hypoxia of the bone marrow. Therefore, this study aimed to investigate the effect of UV LED on leukemia cells under hypoxia. HL-60 cells were irradiated with a UV LED (30 J/m2) and simulated under hypoxia with cobalt chloride. We found that UV LED irradiation or CoCl2 inhibited proliferation, induced apoptosis, decreased the Bcl-2/Bax ratio, and increased the levels of caspase 3, cleaved-caspase 3, and caspase 9 in HL-60 cells. In particular, the combined application of UV and CoCl2 significantly enhanced the apoptosis of HL-60 cells. In conclusion, UV LED in hypoxia exacerbated the inhibition of proliferation and induction of apoptosis and necrosis in HL-60 cells via the regulation of caspase 3/9 and the Bcl-2/Bax ratio-dependent pathway. The application of UV LEDs in hypoxia conditions may be a promising approach to kill residual drug-resistant leukemia cells in autologous grafts.

Considerable improved near-infrared luminescence in ionic-free doped ZnAl2O4 by oxygen defects engineering

Recently, the phosphor for near-infrared LED is of importance, and a lot of the researches have been attracted on the synthesis and composition design. However, the large number of researches for near-infrared luminescent materials mainly focus on activator ions doped inorganic materials, including rare earth ions and transition metal ions. Here, an ionic-free doped NIR phosphor of ZnAl2O4 is proposed for NIR LED through oxygen defects engineering. The spinel-structured ZnAl2O4 phosphors with deficiency of zinc were synthesized by high temperature solid state reaction, which were characterized by a series of techniques, including XRD, UV–Vis, XPS, EPR, DFT calculation, PLE/PL spectroscopy, and temperature-dependent PL spectra analysis. The deficiency of zinc results in the appearance of zinc vacancy (VZn) and oxygen vacancy (VO). Most of the oxygen vacancy is VO+, along with a small content of VO++ in ZnAl2O4. Under the excitation of ultraviolet light at 302 nm, the phosphor outputs a broad near-infrared emission band with the maximum at 715 nm. Higher concentration of zinc deficiency leads to stronger near-infrared luminescence, because of the increased oxygen vacancy. The phosphors exhibited a good thermal stability, and they were successfully packaged on the 285-nm UV LED chip, which outputted bright and intense near-infrared light, indicating that the NIR phosphors synthesized in this work have the prospect application in NIR LED.

The luminescence and mechanism of a novel ultraviolet Li7M1-xAlB12O24: xEu2+ (M=Ca, Sr, Ba) phosphors synthesized by high-temperature solid-state method

The Li7M1-xAlB12O24: xEu2+ (M = Ca、Sr、Ba) phosphors were prepared by the conventional high temperature solid-state reaction. The as-prepared phosphors had novel and attractive ultraviolet emissions at 386 nm (M = Ca), 388 nm (M = Sr), 391 nm (M = Ba) under the excitation of 289 nm, 293 nm, and 304 nm, respectively. The concentration quenching process between Eu2+ ions is determined and the critical quenching concentration of Eu2+ in Li7Ca1-xAlB12O24: xEu2+ phosphor is x = 0.11. The corresponding concentration quenching mechanism is verified as dipole-quadrupole (d-q) interaction. The critical transfer distance of Li7Ca0.89AlB12O24:0.11Eu2+ was determined to be 1.88 nm, Further evaluation on the absorbance spectra indicated that the energy transfer between Eu2+ was little affected by the matrix crystal field. The fluorescence lifetime of Li7Ca0.89AlB12O24: 0.11Eu2+ was 768.5 ns and the quantum efficiency was 55.91%. Therefore, the as prepared Li7M1-xAlB12O24: xEu2+ (M = Ca、Sr、Ba) phosphors exhibited a rare near ultraviolet emission with a potential applications on UV LED and anti-counterfeiting ink.

Fabrication of W-LEDs by Coating Tri-Color Inorganic Phosphors on UV-Diode

YAG:Ce phosphor coated on blue-chip gives many advantages, except the color rendering of the LEDs fabricated by this method is poor due to the lack of red and green colors. This problem can be sorted out by choosing different methods out of the available two different methods. For the first method, the n-UV (near-ultraviolet) LED is coated with a mixture of intense blue, green, and red phosphors to make a white light-emitting diode. Also, if the yellow color phosphor is added, lamps can give better CRI values. So many papers are reported on this type of white LED fabrication technique. In this paper, we have reported the fabrication of white LED lamps by coating three different phosphors i.e. blue, green, and red in the appropriate amount to be mixed and coated on the near UV LED chips. This approach is different from the existing reports because we are using near UV (405-407 nm LEDs) not the UV LED chips in the fabrication of white LEDs in this paper.

A U-bent fiberoptic absorbance biosensor array (ArFAB) for multiplexed analyte detection

Compact and dip-type U-bent fiber optic sensor (U-FOS) probes exhibit remarkably high evanescent wave absorbance (EWA) sensitivity and are highly suitable for label-free multiplexed detection of proteins, virii and bacteria by exploiting their intrinsic optical absorption property in the UV region. Here, we show the design and development of a novel EWA based eight-channel array fiber optic absorbance biosensor (ArFAB) using U-FOS probes for multi-analyte detection or multi-sample analysis in real-time. A proof-of-concept ArFAB is designed to consist of a UV LED (λmax = 285 nm) and a highly sensitive CMOS linear image sensor coupled to a sensor probe module through fan-out (1-to-8) and parallel (8 nos) fiber bundles respectively. The sensor probe module is designed to hold and efficiently couple the light to/from 8 U-FOS probes with the help of ceramic ferrules and mating sleeves. The CMOS line sensor, with 8 coupling fibers equidistantly placed along its length, distinctly quantifies the intensity response from each of the eight U-FOS probes. The ArFAB was systematically validated for reproducible optical intensity measurements and label-free multiplexed detection of proteins and bacteria was realized. Moreover, a novel sandwich immunoassay with plasmonic labels for immunoglobulin G (IgG) with picomolar analyte detection limits at 280 nm wavelength is demonstrated. With mass-producible U-FOS probes and a low-cost optoelectronic instrumentation that can be easily customized for LSPR or any other sensing phenomenon, the ArFAB is highly promising for cost-effective biomolecular interactions, and cell analyses and clinical diagnostic applications.

Laser-Based Synthesis of TiO2-Pt Photocatalysts for Hydrogen Generation.

The development of visible-light active titanium dioxide is one of the key challenges in photocatalysis that stimulates the development of TiO2-based composite materials and methods for their synthesis. Here, we report the use of pristine and Pt-modified dark titanium dioxide prepared via pulsed laser ablation in liquid (Nd:YAG laser, 1064 nm, 7 ns) for photocatalytic hydrogen evolution from alcohol aqueous solutions. The structure, textural, optical, photoelectrochemical, and electrochemical properties of the materials are studied by a complex of methods including X-ray diffraction, low-temperature nitrogen adsorption, electrophoretic light scattering, diffuse reflection spectroscopy, photoelectrochemical testing, and electrochemical impedance spectroscopy. Both the thermal treatment effect and the effect of modification with platinum on photocatalytic properties of dark titania materials are studied. Optimal compositions and experimental conditions are selected, and high photocatalytic efficiency of the samples in the hydrogen evolution reaction (apparent quantum yield of H2 up to 0.38) is demonstrated when irradiated with soft UV and blue LED, i.e., 375 and 410 nm. The positive effect of low platinum concentrations on the increase in the catalytic activity of dark titania is explained.

Real-Time Oil Leakage Detection on Aftermarket Motorcycle Damping System with Convolutional Neural Networks.

In this work, we describe in detail how Deep Learning and Computer Vision can help to detect fault events of the AirTender system, an aftermarket motorcycle damping system component. One of the most effective ways to monitor the AirTender functioning is to look for oil stains on its surface. Starting from real-time images, AirTender is first detected in the motorbike suspension system, simulated indoor, and then, a binary classifier determines whether AirTender is spilling oil or not. The detection is made with the help of the Yolo5 architecture, whereas the classification is carried out with the help of a suitably designed Convolutional Neural Network, OilNet40. In order to detect oil leaks more clearly, we dilute the oil in AirTender with a fluorescent dye with an excitation wavelength peak of approximately 390 nm. AirTender is then illuminated with suitable UV LEDs. The whole system is an attempt to design a low-cost detection setup. An on-board device, such as a mini-computer, is placed near the suspension system and connected to a full hd camera framing AirTender. The on-board device, through our Neural Network algorithm, is then able to localize and classify AirTender as normally functioning (non-leak image) or anomaly (leak image).

Single-shot phase retrieval system using a deep UV LED source with visible light converter fluorescent glass

Single-shot phase retrieval system using a deep UV LED source with visible light converter fluorescent glass

Photoluminescence properties and energy transfer of double perovskite Ca2LaTaO6:Bi3+,Tb3+ phosphor

The improvement of solid-state luminescence technology is an important way to cope with the current severe energy consumption. For the efficient utilization of rare earth ions, Bi3+ and Tb3+ activated Ca2LaTaO6 (CLTO) phosphors were designed and prepared using a solid phase reaction technique. The structural properties of the samples have been studied in detail through XRD, EDS and XPS techniques. Combined with UV–vis reflectance spectroscopy, excitation and emission spectra, the photoluminescence characteristics of CLTO phosphors were analyzed in detail. Bi3+ ions can occupy distinct sites in the CLTO host to create two emission centers. The adjustable multicolor emission is realized in the CLTO:Bi3+,Tb3+ compounds depending on the approximately 100% energy transfer from Bi3+ to Tb3+ ions. By exploring the fluorescence spectra, it was demonstrated that the energy transfer process is contributed by the dipole-dipole interaction mechanism. Besides, the CLTO:Bi3+,Tb3+ phosphors have good thermal stability, suggesting it is a potential luminescent material for UV LEDs.