WO2016202376A1 - Red-emitting luminescence conversion materials - Google Patents

Abstract

The present invention relates to a red-emitting material containing terbium and europium. The material is characterized by an increased absorption in the blue spectrum, whereby the efficiency of LEDs is increased.

Description

 Red emitting luminescence conversion materials

The present application relates to the field of red-emitting

Luminescence conversion materials, in particular those phosphors which contain inorganic or oxidic materials, and light-emitting devices containing these phosphors.

These light-emitting devices are usually designed to employ red emitting phosphors starting from a blue emitting or UV emitting LED (e.g., on (In, Ga) N / (Al, Ga, In) N / (Al, Ga,) N). Such devices may be white-sensitive if more luminescence conversion materials are used, but this is not limiting. Just e.g. In the automotive field, only substantially red-emitting devices, e.g. at reverse lights or

Used brake lights. However, many of these devices and materials used often experience severe thermal quenching. That's why it's a job to have new red-emitting

To provide materials or material systems.

This object is solved by claim 1 of the present invention. Accordingly, a red-emitting inorganic material is presented which includes Tb ³⁺ and Eu ³⁺ .

Surprisingly, it has been found that the use of terbium, in particular the absorption of trivalent europium in the blue light spectrum is greatly improved.

For the purposes of the present invention, the term "red-emitting" means and / or comprises a material which, with suitable excitation, has an emission band between 600 nm and 650 nm In particular, the system according to the invention can achieve at least one of the following advantages in most applications :

The use of the materials according to the invention is easily possible in existing systems

 - The materials show in comparison to conventional red-emitting LED

Phosphors hardly re-absorption

 The materials show higher photo stability and less saturation compared to conventional red-emitting LED phosphors.

In a preferred embodiment, the material is absorbent in the range of> 380 nm to <580 nm, i. it can by means of irradiation of light at least one

Wavelength can be excited in this wavelength range. In this case, the ratio (in mol / mol) of Eu ³⁺ to Tb ³⁺ is preferably from> 0.0005: 1 to <100: 1.

According to a preferred embodiment of the invention, the ratio (in mol / mol) of Eu 3 to Tb 3+ is from> 0.001: 1 to <10: 1. This has been the case in many applications proven present invention. The ratio (in mol / mol) of Eu 3 to Tb 3 + is particularly preferably from> 0.005: 1 to <5: 1, more preferably> 0.01: 1 to <2: 1, more preferably> 0.02: 1 to <1: 1, and most preferably still more preferably> 0.05: 1 to <0.5: 1. According to a preferred embodiment of the invention, the material according to the invention comprises an oxidic material. Preferably, it consists essentially of it.

The term "essentially" for the purposes of this invention means or comprises in particular> 80 (weight) percent, more preferably> 90 (weight) percent, further preferably> 95 (weight) percent and most preferably> 97 (weight percent ,

These materials have proven particularly useful in practice. According to a preferred embodiment of the invention, the material according to the invention comprises a material in which the terbium sits on a crystal lattice site with octahedral, dodecahedral or cubic symmetry. The material according to the invention preferably consists essentially of it. It has been found that these materials result in a particularly high splitting of the F ₆ - ground state of terbium, which has proven to be particularly positive for the present invention.

According to a preferred embodiment of the present invention, the material according to the invention contains a tungstate, molybdate, silicate, germanate, zirconate, hafnate or mixtures thereof. These materials have proven particularly useful. The material according to the invention preferably consists essentially of it. It preferably contains the material according to the invention a tungstate, molybdate or mixtures thereof.

The term "molybdate" and / or tungstate "refers in particular to a material whose lattice or host material to> 50 (mol / mol), preferably> 70 consists of an oxide containing molybdenum and / or tungsten.

According to a preferred embodiment of the present invention, the material according to the invention contains a material selected from the group comprising:

Li ₃ Ba ₂ (Tbi_ _x _ _y Eu _x Ln _y ) ₃ (Moi_ _z W _z ) ₈ 032,

A ₃ AE ₂ (Tbi_ _x _ _y Eu _x Ln _{y) 3} (Moi_ _z W _{z) 8} 0 ₃₂

A (Tbi_ _x _ _y Eu _x Ln _y) (Moi_ _z W _{z) 2} 0 _8,

(Tb _! _ _X _ _y Eu _x Ln _y ) ₂ (Mo i_ _z W _z ) 0 ₆ ,

(Tb i_ _x _ _y Eu _x Ln _{y) 2} (Mo i_ _z W _{z) 2} 0 _9,

(Tbi_ _x _ _y Eu _x Ln _{y) 2} (Moi_ _z W _{z) 4} Oi5,

(Tbi_ _x _ _y Eu _x Ln _{y) 2} Si0 _5,

(Tbi_ _x _ _y Eu _x Ln _{y) 2} Si ₂ 0 _7,

A (Tbi_ _x _ _y Eu _x Ln _y) Si0 _4,

Ba ₂ (Tbi_ _x _ _y Eu _x Ln _{y) 2} Si ₄ 0i _3,

AE ₂ (Tbi_ _x _ _y Eu _x Ln _{y) 2} Si ₄ 0i _3,

Sr ₃ (Tbi_ _x _ _y Eu _x Ln _{y) 2} Si ₆ 0i _8,

AE ₃ (Tbi_ _x _ _y Eu _x Ln _{y) 2} Si ₆ 0i _8,

(Tb i_ _x _ _y Eu _x Ln _y ) ₂ Ge0 ₅ ,

(Tb i_ _x _ _y Eu _x Ln _{y) 2} Ge ₂ 0 _7,

A (Tbi_ _x _ _y Eu _x Ln _y) Ge0,

Ba ₂ (Tbi_ _x _ _y Eu _x Ln _{y) 2} Ge ₄ 0i _3,

AE ₂ (Tbi_ _x _ _y Eu _x Ln _{y) 2} Ge ₄ 0i _3,

Sr ₃ (Tbi_ _x _ _y Eu _x Ln _{y) 2} Ge ₆ 0i8 AE ₃ (Tb i _ _{x y} Eu _x Ln _y ) ₂ Ge ₆ 01 ₈

(Tbi_ _x _ _y Eu _x Ln _{y) 2} (Gei_ _a _bZr _a Hf _b) 0 _5,

(Tbi_ _x _ _y Eu _x Ln _{y) 2} (Gei_ _a _bZr _a Hf _{b) 2} 0 _7,

A (Tb i_ _x _ _y Eu _x Ln _y) (Ge i_ _a _ _{b a} Zr Hf _b) 0 _4,

Ba ₂ (Tbi_ _x _ _y Eu _x Ln _{y) 2} (Gei_ _a _ _{b a} Zr Hf _{b) 4} 0i _3,

Sr ₃ (Tbi_ _x _ _y Eu _x Ln _{y) 2} (Gei_ _a _ _{b a} Zr Hfb) ₆ 0i ₈ (in each case independently for each material) Ln = La, Gd, Lu, Y or mixtures thereof

 A = Li, Na, K, Rb, Cs or mixtures thereof, preferably Li,

 AE = Sr, Ca, Br or mixtures thereof, preferably Ba and / or Sr.

x> 0 and <1 and y> 0 and <1 and a, b> 0 and <0.2 (where x and y are chosen so that the ratio of Tb ³⁺ and Eu ^{3+ is} in the ratio indicated), and

z> 0 and <l. or mixtures of these materials. The material according to the invention preferably consists essentially of it. Particularly preferred materials are Li ₃ Ba ₂ (Tbi_ _x _ _y Eu _x Ln _{y) 3} (Moi_ _z W _{z) 8} 0 _32, A (Tbi_ _x _ _y Eu _x Ln _y) (M _0l _ _z W _{z) 2} 0 ₈ , (Tb ₁ - _x - _y Eu _x Ln _y ) ₂ (Mo ₁ - _z W _z ) 0 ₆ , (Tb ₁ - _x - _y Eu _x Ln _y ) ₂ (Mo ₁ - _z W _z ) ₂ 0 _9, (Tb _1-x _ _y Eu _x Ln _{y) 2} (Moi_ _z W _{z) 4} Oi5 or mixtures thereof, wherein A, Ln, x and y are as described above. Preferably, the material consists essentially of it. Particularly preferred is A ₃ AE ₂ (Tbi_ _x _ _y Eu _x Ln _y ) ₃ (Moi_ _z W _z ) ₈ 0 ₃₂ , in particular

Li ₃ Ba ₂ (Tbi_ _x _ _y Eu _x Ln _{y) 3} (Moi_ _z W _{z) 8} 0 ₃₂ and / or Li ₃ Ba ₂ (Tbi_ _x Eu _{x) 3} (Moi_ _z W _{z) 8} 0 _32nd According to a preferred embodiment, the material comprises a material of the following table or preferably consists thereof:

wobei x und y wie oben beschrieben sind.

where x and y are as described above.

According to a preferred embodiment of the invention, the material of the invention does not comprise (Tbi_ _x _ _y Eu _x Ln _{y) 2} (Moi_ _z W _{z) 3} Oi. ₂

The present invention also relates to a light-emitting device comprising a material according to the invention.

According to a preferred embodiment of the invention, the device comprises a blue and / or UV-emitting nitride material, preferably based on the material system (In, Ga) N / (Al, Ga, In) N / (Al, Ga,) N) , It has been found in many embodiments of the present application that the achievable positive effects are strongest here. The above-mentioned and the claimed components to be used according to the invention described in the exemplary embodiments are not subject to special conditions of size, shape, material selection and technical design, so that the selection criteria known in the field of application can be used without restriction.

Further details, features and advantages of the subject matter of the invention will become apparent from the subclaims and from the following description of the drawings and examples, which are to be understood purely illustrative.

In the figures show

1 shows an XRD spectrum of the compound according to Example I. FIG. 2 shows an emission spectrum of the compound according to Example I. FIG

Fig. 3 is an excitation spectrum of the compound lt. Example I.

4 shows a reflection spectrum of the compound according to Example I

5 shows an XRD spectrum of the compound according to Example II

6 shows an emission spectrum of the compound according to Example II. FIG. 7 shows an excitation spectrum of the compound according to Example II

8 shows a reflection spectrum of the compound according to Example II

9 shows an XRD spectrum of the compound according to Example III FIG. 10 an emission spectrum of the compound according to Example III FIG. 11 an excitation spectrum of the compound according to Example III FIG. 12 a reflection spectrum of the compound according to Example III. 13 shows an XRD spectrum of the compound according to Example IV. FIG. 14 shows an emission spectrum of the compound according to Example IV

FIG. 16 shows an XRD spectrum of the compound according to Example V FIG. 17 shows an emission spectrum of the compound according to Example V FIG. 18 shows an excitation spectrum of the compound according to Example IV FIG. 19 shows an XRD spectrum of the compound according to Example VI

FIG. 21 shows an emission spectrum of the compound according to Example VI FIG. 21 shows an excitation spectrum of the compound according to Example VI FIG. 22 shows an XRD spectrum of the compound according to Example VII

FIG. 23 shows an emission spectrum of the compound according to Example VII. FIG

FIG. 24 shows an excitation spectrum of the compound according to Example VII; FIG. such as

Fig. 25 shows an emission spectrum of an LED according to Example VIII and a comparative example. The present invention will be described by way of examples, which are to be regarded as purely illustrative and not restrictive. EXAMPLE I

Example I relates to Li3Ba ₂ (o0 ₄₎ 8, which was prepared as follows (Tbo ₉₉ 5Euo.oo5.): 0.7894 g (4.000 mmol) BAC0 _3, 2.3030 g (16.000 mmol) Mo0 _3, 0.2217 g (3.000 mmol) Li ₂ C0 ₃ , 0.0053 g (0.015 mmol) Eu ₂ 0 ₃ and 11204 g (1.499 mmol) Tb ₄ 0 ₇ were thoroughly ground in a mortar with a little acetone as a grinding aid. The resulting powder was dried, transferred to a porcelain dish and calcined in air at 800 ° C for 10 hours.

1 shows the XRD, FIG. 2 the emission, FIG. 3 the excitation and FIG. 4 the reflection spectrum of the compound.

EXAMPLE II:

Example II refers to Li ₃ Ba ₂ (Tbo. ₉ 5Euo.o 5) (MoO ₄ ) 8, which consists of 0.7894 g (4,000 mmol) BaC0 ₃ , 2.3030 g (16,000 mmol) MoO ₃ , 0.2217 g (3,000 mmol) Li ₂ C0 ₃ , 0.0528 g (0.150 mmol) of Eu ₂ 0 ₃ and 1.0655 g (1.425 mmol) of Tb ₄ 0 _{7 was} prepared analogously to Example I.

5 shows the XRD, FIG. 6 the emission, FIG. 7 the excitation and FIG. 8 the reflection spectrum of the compound.

EXAMPLE III:

Example III relates to Li ₃ Ba ₂ (Tbo _.6 Euo. ₄₎ (Mo0 _{4) 8,} which consists of 0.7894 g (4.000 mmol) BAC0 _3, 2.3030 g (16.000 mmol) Mo0 _3, 0.2217 g (3.000 mmol) of Li ₂ C0 ₃ , 0.0528 g (0.150 mmol) of EU2O3 and 1.0655 g (1.425 mmol) of Tb ₄ 0 ₇ were prepared analogously to Example I.

9 shows the XRD, FIG. 10 the emission, FIG. 11 the excitation and FIG. 12 the reflection spectrum of the compound.

EXAMPLE IV:

Example IV refers to Li ₃ Ba ₂ (Tbo.9Euo.i) (MoC) ₄ ) 8, which consists of 0.7894 g (4,000 mmol) of BaC0 ₃ , 2.3030 g (16,000 mmol) of MoO ₃ , 0.2217 g (3,000 mmol) of Li ₂ C0 ₃ , 0.1056 g (0.300 mmol) Eu ₂ 0 ₃ and 1.0094 g (1.350 mmol) Tb ₄ 0 _{7 was} prepared analogously to Example I.

Figure 13 shows the XRD, Figure 14 the emission, and Figure 15 the excitation spectrum of the compound.

EXAMPLE V:

Example V refers to Li ₃ Ba ₂ (Tbo.8Euo.2) (MoO ₄ ) ₈ , which consists of 0.7894 g (4.000 mmol) BaC0 ₃ , 2.3030 g (16.000 mmol) Mo0 ₃ , 0.2217 g (3.000 mmol) Li ₂ C0 ₃ , 0.1056 g (0.300 mmol) of Eu ₂ 0 ₃ and 1.0094 g (1.350 mmol) of Tb ₄ 0 _{7 was} prepared analogously to Example I.

FIG. 16 shows the XRD, FIG. 17 shows the emission spectrum, and FIG. 18 shows the excitation spectrum of the compound.

EXAMPLE VI:

Example VI refers to Li ₃ Ba ₂ (Tbo. Euo.6) (MoO ₄ ) ₈ , which consists of 0.7894 g (4,000 mmol) of BaC0 ₃ , 2.3030 g (16,000 mmol) of MoO ₃ , 0.2217 g (3,000 mmol) of Li ₂ C0 ₃ , 0.6335 g (1.800 mmol) Eu ₂ 0 ₃ and 0.4486 g (0.600 mmol) Tb ₄ 0 _{7 was} prepared analogously to Example I. Fig. 19 shows the XRD, Fig. 20 the emission, and Fig. 21 the excitation spectrum of the compound. EXAMPLE VII:

Example VII relates to Li ₃ Ba ₂ (Tbo. Euo.8 ₂₎ (Mo0 ₄₎ 8, which consists of 0.7894 g (4.000 mmol) BAC0 _3, 2.3030 g (16.000 mmol) Mo0 _3, 0.2217 g (3.000 mmol) of Li ₂ C0 ₃ , 0.8446 g (2.400 mmol) Eu ₂ 0 ₃ and 0.2243 g (0.300 mmol) Tb ₄ 0 _{7 was} prepared analogously to Example I.

Fig. 22 shows the XRD, Fig. 23 the excitation and Fig. 24 the emission spectrum of the compound. EXAMPLE VIII:

In Example VIII, the compound from Example III was considered in combination with an (In, Ga) N LED (λ _ρε! = 468 nm). As a comparative example, an identical LED is selected, only Li ₃ Ba ₂ (Lao.6Euo. ₄₎ (Mo0 ₄₎ 8 as a red-emitting substance.

Fig. 25 shows the emission spectrum of both the LED (broken line) and the excitation spectra of a phosphor of the present invention (solid line) and the comparative example (dotted line). One can clearly see the greatly increased emission for the excitation between 475 and 500 nm, which shows the advantage of the combination of terbium and europium (III).

The individual combinations of the components and the features of the already mentioned embodiments are exemplary; the exchange and substitution of these teachings with other teachings contained in this document with the references cited are also expressly contemplated. Those skilled in the art will recognize that variations, modifications and other implementations described herein may also occur without departing from the spirit and scope of the invention.

Accordingly, the above description is exemplary and not as

restrictive. The word "comprising" used in the claims does not exclude other ingredients or steps The indefinite article "a" does not exclude the meaning of a plural. The mere fact that certain measures are recited in mutually different claims does not make it clear that a combination of these measures can not be used to the advantage. The scope of the invention is defined in the following claims and in the appended equivalents.

Claims

Red-emitting inorganic material containing Tb and Eu. The material of claim 1, wherein the ratio (in mol / mol) of Eu 3 to Tb 3+ is from> 0.0005: 1 to <100: 1. Material according to claim 1 or 2, comprising an oxidic material. A material according to any one of claims 1 to 3, comprising a material in which the terbium sits on a crystal lattice site of octahedral, dodecahedral or cubic symmetry. Material according to one of claims 1 to 4, containing a tungstate, molybdate, silicate, germanate, zirconate, hafnate or mixtures thereof Material according to one of claims 1 to 5, comprising a material selected from the group According to a preferred embodiment of the present invention, the material according to the invention contains a material selected from the group comprising: Li ₃ Ba ₂ (Tbi_ _x _ _y Eu _x Ln _{y) 3} (Moi_ _z W _{z) 8032,} A (Tbi_ _x _ _y Eu _x Ln _y) (Moi_ _z W _{z) 2} 0 ₈ (Tbi_ _x _ _y Eu _x Ln _y ) ₂ (Mo i_ _z W _z ) 0 ₆ , (Tb _! _ _X _ _y Eu _x Ln _y ) ₂ (Mo i_ _z W _z ) ₂ 0 ₉ , (Tb _! _ _X _ _y Eu _x Ln _{y) 2} (Mo i_ _z W _{z) 4} 0 (Tbi_ _x _ _y Eu _x Ln _{y) 2} Si0 _5, (Tbi_ _x _ _y Eu _x Ln _{y) 2} Si ₂ 0 ₇ A (Tbi_ _x _ _y Eu _x ln _y) Si0 _4, Ba ₂ (Tbi_ _x _ _y Eu _x ln _{y) 2} Si ₄ 0i _3, Sr ₃ (Tbi_ _x _ _y Eu _x ln _{y) 2} Si ₆ 0i _8, (Tbi_ _x _ _y Eu _x ln _{y) 2} Ge0 _5, (Tbi_ _x _ _y Eu _x Ln _{y) 2} Ge ₂ 0 ₇ A (Tbi_ _x _ _y Eu _x Ln _y) Ge0 _4, Ba ₂ (Tbi_ _x _ _y Eu _x Ln _{y) 2} Ge ₄ 0i _3, Sr ₃ (Tbi_ _x _ _y Eu _x Ln _{y) 2} Ge ₆ 0i _8, A ₃ AE ₂ (Tbi_ _x _ _y Eu _x Ln _{y) 3} (Moi_ _z W _{z) 8} 0 _32, with (respectively independent for each material) Ln = La, Gd, Lu, Y or mixtures thereof  A = Li, Na, K, Rb, Cs or mixtures thereof  AE = Ca, Sr, Ba or mixtures thereof x> 0 and <1 and y> 0 and <1 (where x and y are chosen such that the ratio of Tb ³⁺ and Eu ^{3+ is} in the stated ratio)  z> 0 and <l. or mixtures thereof. 7. Material according to one of claims 1 to 6, comprising a material selected from the group Li3Ba ₂ (Tbi_ _x _ _y Eu _x Ln _y ) 3 (Moi_ _z W _z ) 8032, A (Tbi_ _x _ _y Eu _x Ln _y ) (Moi_ zW _{z) 2} 0 ₈ (Tbi_ _x _ _y Eu _x Ln _{y) 2} (Moi_ _z W _z) 0 ₆ (Tbi_ _x _ _y Eu _x Ln _{y) 2} (Moi_ _z W _{z) 2} 0 _9, (Tbi_ _x _ yEu _x Ln _{y) 2} (Moi_ _z W _{z) 4} Oi5, A ₃ AE ₂ (Tbi_ _x _ _y Eu _x Ln _{y) 3} (Moi_ _z W _{z) 8} 03 ₂ or mixtures thereof. 8. A light-emitting device comprising a material according to any one of claims 1 to 7.