Luminescence properties and energy transfer behavior of colour-tunable white-emitting Sr4Al14O25 phosphors with co-doping of Eu2+, Eu3+ and Mn4+

Dy 3+ -doped CaAl 12 O 19 phosphors were synthesized utilizing a combustion method.Crystal structure and morphological examinations were performed respectively using X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques to identify the phase and morphology of the synthesized samples. Fourier transform infrared spectroscopy (FTIR) estimations were carried out using the KBr method.Photoluminescence properties (excitation and emission) were recorded at room temperature. CaAl 12 O 19 :Dy 3+ phosphor showed two emission peaks respectively under a 350-nm excitation wavelength, centered at 477 nm and 573 nm. Dipole-dipole interaction via nonradiative energy shifting has been considered as the major cause of concentration quenching when Dy 3+ concentration was more than 3 mol%. The CIE chromaticity coordinates positioned at (0.3185, 0.3580) for the CaAl 12 O 19 :0.03Dy 3+ phosphor had a correlated color temperature (CCT) of 6057 K, which is situated in the cool white area. Existing results point out that the CaAl 12 O 19 :0.03Dy 3+ phosphor could be a favorable candidate for use in white light-emitting diodes (WLEDs). KEYWORDS aluminate, concentration quenching, Dy 3 + , photoluminescence, WLEDs | INTRODUCTIONAt the present time, the development of energy-saving lighting is an essential core interest for researchers. Large amounts of power can be saved by using efficient energy-saving light sources. Traditional incandescent and fluorescent lamps, with their resulting heat or gas release, have related colossal energy losses. [1] The use of energy proficient solid-state lighting appliances, for example compact fluorescent lamps (CFLs) and light-emitting diodes (LEDs), to deliver white light is an attractive alternative. Due to the above concern, the production of phosphors with excellent properties is an essential prerequisite. The efficacy of white light-emitting diodes (WLEDs) has surpassed that of incandescent lamps and fluorescent lamps. Due to their exceptional luminescence features, improved stability, energy-efficient nature, prominent luminescence efficiency, ecological amicability, and low cost, research into WLEDs has become more important. [2][3][4] WLEDs are mostly fabricated by applying three different techniques: (i) by making use of a mixture of red-green-blue (RGB) LEDs;(ii) through the utilization of ultraviolet (UV) LEDs to excite RGB phosphors; and (iii) by employing blue LEDs to pump single-phase yellow or blended green and red phosphors. [1,5] At the present time, blue emitting chips combined with yellow phosphors (YAG:Ce 3+ ) are acknowledged as existing industrial WLEDs. Nevertheless, inferable from red light effect insufficiency, low color rendering index and high correlated color temperature (CCT) are commonly experienced by phosphors in this group. High CCT and low color rendering index (CRI) are not good factors when providing domiciliary or office lighting. This hindrance can be resolved by utilizing tricolor WLEDs dependent on red, green, and blue phosphors [6][7][8] . This ...

show abstract

“…Vacancy V″ Ca would behave as an electron contributor, whereas Dy • Ca defects are electrons acceptors . This process can be expressed as follows:

3 {Ca}^{2 +} + 2 {Dy}^{3 +} \to normalV "_{Ca} + 2 {Dy}^{•}_{Ca}

…”

Section: Resultsmentioning

confidence: 99%

Study of luminescence properties of dysprosium‐doped CaAl₁₂O₁₉ phosphor for white light‐emitting diodes

Dev

Selot²,

Nair

et al. 2019

Luminescence

View full text Add to dashboard Cite

show abstract

“…A broad peak centred at 496 nm and 514 nm corresponding to the transition 4f 6 5d 1 -4f 7 has been observed corresponding to Eu 2+ . [53][54][55] As the amount of Eu doping was very miniscule, the doping amount was increased to 2.5% to obtain a relatively higher intensity of emission. Furthermore, relatively weaker peaks at 595 nm, 616 nm, 653 nm and 703 nm, characteristic of Eu 3+ , were also observed in the photoluminescence spectra of the materials.…”

Section: Surface Area Analysismentioning

confidence: 99%

Defect induced “super mop” like behaviour of Eu³⁺-doped hierarchical Bi₂SiO₅nanoparticles for improved catalytic and adsorptive behaviour

et al. 2020

View full text Add to dashboard Cite

show abstract

“…In order to verify the effect of the interstitial defects ((Y) i˙˙˙, (Al) i˙˙˙) and substitution defects on the reduction reaction, the charge compensation is added in Y (1−x) AB: xEu system. When two Y 3+ ions are replaced by three Eu 2+ ions, the monition of electronic defects in the system can be presented in Equations (9)(10)(11)(12).…”

Section: Incomplete Reductionmentioning

confidence: 99%

“…Fundamental Building Block of the common borate crystals is BO 3 . [9][10][11] However, it is well known that the valence state of Eu ion is hard to control in borates, which limits the application of the multiple valence coexistence ions, so it is desirable to explore the mechanism of coexistence of multiple valence ions clearly. Therefore, rare earth-doped borate phosphors are widely applied in solid-state lasers, 1,2 plasma display panel (PDP), 3,4 optical communication, 5,6 and light-emitting diodes (LEDs).…”

Section: Introductionmentioning

confidence: 99%

“…7,8 Currently, coexistence phenomena of multiple valence ions are exceedingly common in borates, which have been utilized to obtain the white light-emitting for LEDs, especially, Eu 2+ and Eu 3+ . [9][10][11] However, it is well known that the valence state of Eu ion is hard to control in borates, which limits the application of the multiple valence coexistence ions, so it is desirable to explore the mechanism of coexistence of multiple valence ions clearly.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Coexistence mechanism of Eu²⁺/Eu³⁺ ions in YAl₃(BO₃)₄: Crystal structure, luminescence property, and substitution defects

Liu

Wang

et al. 2019

J Am Ceram Soc

View full text Add to dashboard Cite

The coexistence mechanism of Eu 2+ and Eu 3+ ions in YAl 3 (BO 3 ) 4 host under different reducing conditions is investigated and confirmed in great detail, which can be described by three aspects as following. First, Eu 3+ is protected by the layered structure of YAl 3 (BO 3 ) 4 . Second, the number of the interstitial defects ((Al) i˙˙˙, (Y) i˙˙˙) increases with increasing Eu 2+ to maintain the charge balance of the system. And these defects can capture free electrons which are used for the reduction of Eu 3+ . Finally, free holes become more and more with the number of nonequivalent substitution defects (Eu Y ') increasing, which make the 5d electrons of Eu 2+ easily escape to the conduction band and Eu 2+ convert to Eu 3+ . This work will be of great significance to research coexistence of multiple valence ions in the structure of borate and defect motion with nonequivalent substitution.presents polysynthetic twin which is composed of a number of parallel single crystals. The parallel layer structure is beneficial for the movement of electrons and defects. 26 Many possibilities for the luminescence of activators are created since its unique structure. Recently, Prokhorov et al. reported an interesting phenomenon about EuAl 3 (BO 3 ) 4 crystals. The X-ray irradiation can modify the color of the EuAl 3 (BO 3 ) 4 crystal, and annealing of the crystal at 600°C can lead to the restoration of the original color. It was concluded that Eu 2+ ion located at the Eu 3+ site in the EuAl 3 (BO 3 ) 4 crystal lattice. 27 However, when Eu concentration is low, Eu 3+ is always existed in YAB no matter how strong the reduction atmosphere is. Generally, the reasons for the coexistence of multivalent ions are imbalance of the charge, defects, and crystal structure. 28 For further exploration, Eu 2+ /Eu 3+ -doped YAl 3 (BO 3 ) 4 phosphors are synthesized in CO or H 2 atmospheres. The structure and morphological characteristics are studied by the X-ray diffraction (XRD), the field emission scanning electron microscope (SEM), and diameter analyzer. The luminescence properties and luminescence decay curves are investigated in detail. Meanwhile, the energy transfer process and behavior of intrinsic and substitution defects are further analyzed. The model of charge compensation is established. The surface chemical compositions of YAB:Eu are determined by X-ray Photoelectron Spectroscopy (XPS). Moreover, the influence of crystal structure and defect motion on incomplete reduction is also explored.

show abstract

Luminescence properties and energy transfer behavior of colour-tunable white-emitting Sr₄Al₁₄O₂₅ phosphors with co-doping of Eu²⁺, Eu³⁺ and Mn⁴⁺

Abstract: Eu2+, Eu3+ and Mn4+ co-doped Sr4Al14O25 phosphors were synthesized in air by high temperature solid-state reaction.

Cited by 27 publications

References 39 publications

Study of luminescence properties of dysprosium‐doped CaAl₁₂O₁₉ phosphor for white light‐emitting diodes

Study of luminescence properties of dysprosium‐doped CaAl₁₂O₁₉ phosphor for white light‐emitting diodes

Defect induced “super mop” like behaviour of Eu³⁺-doped hierarchical Bi₂SiO₅nanoparticles for improved catalytic and adsorptive behaviour

Coexistence mechanism of Eu²⁺/Eu³⁺ ions in YAl₃(BO₃)₄: Crystal structure, luminescence property, and substitution defects

Contact Info

Product

Resources

About

Luminescence properties and energy transfer behavior of colour-tunable white-emitting Sr4Al14O25 phosphors with co-doping of Eu2+, Eu3+ and Mn4+

Abstract: Eu2+, Eu3+ and Mn4+ co-doped Sr4Al14O25 phosphors were synthesized in air by high temperature solid-state reaction.

Cited by 27 publications

References 39 publications

Study of luminescence properties of dysprosium‐doped CaAl12O19 phosphor for white light‐emitting diodes

Study of luminescence properties of dysprosium‐doped CaAl12O19 phosphor for white light‐emitting diodes

Defect induced “super mop” like behaviour of Eu3+-doped hierarchical Bi2SiO5nanoparticles for improved catalytic and adsorptive behaviour

Coexistence mechanism of Eu2+/Eu3+ ions in YAl3(BO3)4: Crystal structure, luminescence property, and substitution defects

Contact Info

Product

Resources

About

Luminescence properties and energy transfer behavior of colour-tunable white-emitting Sr₄Al₁₄O₂₅ phosphors with co-doping of Eu²⁺, Eu³⁺ and Mn⁴⁺

Study of luminescence properties of dysprosium‐doped CaAl₁₂O₁₉ phosphor for white light‐emitting diodes

Study of luminescence properties of dysprosium‐doped CaAl₁₂O₁₉ phosphor for white light‐emitting diodes

Defect induced “super mop” like behaviour of Eu³⁺-doped hierarchical Bi₂SiO₅nanoparticles for improved catalytic and adsorptive behaviour

Coexistence mechanism of Eu²⁺/Eu³⁺ ions in YAl₃(BO₃)₄: Crystal structure, luminescence property, and substitution defects