CN104876579A

CN104876579A - Novel negative thermal expansion light-emitting ceramic material HfScMo2VO12 and synthesis method thereof by solid-phase sintering

Info

Publication number: CN104876579A
Application number: CN201510241655.2A
Authority: CN
Inventors: 梁二军; 程永光; 葛向红; 袁保合; 陈冬霞; 郭娟; 毛彦超; 晁明举
Original assignee: Zhengzhou University
Current assignee: Zhengzhou University
Priority date: 2015-05-13
Filing date: 2015-05-13
Publication date: 2015-09-02

Abstract

The invention discloses a novel negative thermal expansion light-emitting ceramic material, belonging to the field of inorganic nonmetal materials. The molecular formula is HfScMo2VO12. The invention also discloses a synthesis method of the novel negative thermal expansion light-emitting ceramic material by solid-phase sintering, which comprises the following steps: (1) mixing HfO2, Sc2O3, MoO3 and V2O5 in a mole ratio of 2:1:4:1, and grinding uniformly; (2) sintering the uniform raw materials at 700-800 DEG C in an air atmosphere for 0.5-7 hours to obtain the target product HfScMo2VO12. The novel negative thermal expansion light-emitting ceramic material HfScMo2VO12 disclosed by the invention has stable negative thermal expansivity at -130-600 DEG C, can emit white fluorescence under the excitation of 330nm or 380nm light, and has engineering application value.

Description

A kind of novel negative thermal expansion luminescent ceramic materials HfScMo 2vO 12and solid state sintering synthetic method

Technical field

The invention belongs to field of inorganic nonmetallic material, be specifically related to a kind of novel negative thermal expansion luminescent ceramic materials HfScMo ₂vO ₁₂and solid state sintering synthetic method.

Background technology

" expanding with heat and contract with cold " is one of modal phenomenon of nature; in the occasion that high temperature changes or changes greatly; the thermal stresses produced due to differing materials thermal expansion coefficient difference usually can cause the performance index of material or device to be deteriorated, and brings a lot of puzzlement to the life of people.The material with " pyrocondensation cold expanding " performance is defined as negative thermal expansion material, and the discovery of negative thermal expansion material makes investigator see the coefficient of expansion different approach that cause " thermal mismatching " problem of solution due to material.Thus, negative thermal expansion material is subject to the extensive concern of investigators day by day.People wish that by this material and general positive thermal expansion material compound, thus the thermal expansivity realizing matrix material is controlled, is even zero by research negative expansion (NTE) material.This matrix material can reduce the thermal stresses that material produces when temperature sharply changes to greatest extent, thus increases the heat shock resistance intensity of material, can be widely used in the fields such as aerospace, optics, the manufacture of photoelectron precision instrument.

The time of developing into existing decades now of negative thermal expansion material, at present, the oxide compound negative thermal expansion material generally studied mainly comprises LiAlSiO ₄, ZrV ₂o ₇, ZrW ₂o ₈, Sc ₂mo ₃o ₁₂deng series, these materials all obtain extensive concern because of its property.But not perfect for the research of existing material, also do not obtain large-scale application so far, raw-materially to choose, absorptive impact, phase transformation, mechanical property the problems demand such as raising, complex manufacturing solve.Such as, ZrW ₂o ₈be at room temperature metastable phase material, undergo phase transition at about 150 DEG C, easily decompose with other materials compound tense; ZrV ₂o ₇be at room temperature super cell's structure of 3 × 3 × 3, more than 102 DEG C, only just change the normal configuration of 1 × 1 × 1 into, show negative expansion; Absorption and the release of crystal water cause the huge pucker & bloat of material simultaneously, and the mechanical property of crystallization is deteriorated, and restrict its application.Up to the present, the negative thermal expansion material kind found is very limited, and the research especially with luminescent properties negative thermal expansion ceramic rarely has report.

Therefore, research and develop a kind of negative expansion stable performance, technique simple, be applicable to large-scale production and the novel negative thermal expansion material with luminescent properties is very necessary and tool significance.

Summary of the invention

The object of the present invention is to provide a kind of novel negative thermal expansion luminescent ceramic materials HfScMo of stable performance ₂vO ₁₂, provide the solid state sintering synthetic method of this novel negative thermal expansion luminescent ceramic materials to be then another object of the present invention.

Based on above-mentioned purpose, the present invention by the following technical solutions: a kind of novel negative thermal expansion luminescent ceramic materials, its molecular formula is: HfScMo ₂vO ₁₂.

The solid state sintering synthetic method of described novel negative thermal expansion luminescent ceramic materials, comprises the following steps:

(1) raw material HfO in molar ratio ₂: Sc ₂o ₃: MoO ₃: V ₂o ₅=2:1:4:1 mixes and grinds evenly;

(2) uniform raw material will be ground in air atmosphere, at 700 ~ 800 DEG C, sinter 0.5 h ~ 7 h, obtain target product HfScMo ₂vO ₁₂.

Further, in step (1), add dehydrated alcohol after raw material mixing and grind, can be abundant by raw mill quickly and evenly.

Further, in step (1), milling time is 2 h, and raw material can be made fully to be ground.

In addition, in step (2), before sintering, the raw material mixed can be carried out compressing tablet process, take conveniently.

The present invention has the following advantages:

1, novel negative thermal expansion luminescent ceramic materials provided by the invention, molecular formula is HfScMo ₂vO ₁₂, it has stable negative expansion character within the scope of-130 ~ 600 DEG C ,-130 ~ 400 ^oc and 30 ~ 600 ^ocoefficient of linear expansion in C temperature range is respectively-2.78 × 10 ^-6oc ^-1(-130 ^oc ~ 400 ^oand-3.10 × 10 C) ^-6oc ^-1(30 ~ 600 ^oc), and this luminescent ceramic materials can send white fluorescent under the exciting of 330 nm or 380 nm length ultraviolet light, has engineer applied and is worth.

2, solid state sintering synthetic method provided by the invention can be carried out under atmospheric air atmosphere, and its reaction process is simple, and sintering velocity is fast, the time is short, and sintering temperature controls 700 ~ 800 ^oc, such sintering condition can make raw material reaction abundant, and the product purity made is high, is applicable to batch production.

Accompanying drawing explanation

Fig. 1 is the XRD figure spectrum (700 of 1# product ^oc sinters 5 h);

Fig. 2 is the XRD figure spectrum (750 of 2# product ^oc sinters 5 h);

Fig. 3 is the XRD figure spectrum (800 of 3# product ^oc sinters 5 h);

Fig. 4 is the XRD figure spectrum (800 of 4# product ^oc sinters 0.5 h);

Fig. 5 is the XRD figure spectrum (800 of 5# product ^oc sinters 7 h);

Fig. 6 is that the relative length of 3# product is with probe temperature (-130 ^oc ~ 400 ^oc) change curve;

Fig. 7 is the HfScMo of 3# product ₂vO ₁₂relative length with probe temperature (30 ~ 600 ^oc) change curve;

Fig. 8 is the HfScMo of 3# product synthesis ₂vO ₁₂fluorescence photo under 325nm wavelength laser excites;

Fig. 9 is the HfScMo of 3# product synthesis ₂vO ₁₂fluorescence spectrum figure respectively under 330nm and 380nm wavelength light excites.

Embodiment

Below in conjunction with embodiment, the present invention is described in detail.

embodiment 1

A kind of novel negative thermal expansion luminescent ceramic materials, its molecular formula is: HfScMo ₂vO ₁₂.

The solid state sintering synthetic method of this novel negative thermal expansion luminescent material, comprises the following steps: (1) is by analytical reagent HfO ₂, Sc ₂o ₃, MoO ₃and V ₂o ₅zr:Sc:Mo:V=1:1:2:1 in molar ratio, i.e. HfO ₂: Sc ₂o ₃: MoO ₃: V ₂o ₅=2:1:4:1 mixes in agate mortar, grinds 2 h after adding dehydrated alcohol.

(2) under single shaft direction pressure is 300 Mpa conditions, the process of uniform raw material compressing tablet will be ground, the furnace temperature of low temperature tube furnace is set to 700 DEG C, after low temperature tubular type in-furnace temperature reaches preset temp and is stable, the corundum crucible that sample is housed is put into tube furnace, sinter 5 h in atmospheric air atmosphere, naturally cooling in tube furnace, obtain 1# product.

embodiment 2 ~ 5

With reference to said process, change temperature and time, prepare other products respectively, production code member and condition list in table 1.

Product under table 1 differential responses condition

The XRD figure spectrum that 1 ~ 5# product is corresponding is shown in Fig. 1 ~ 5, does not occur the peak of raw material and possible intermediate product peak in the XRD figure spectrum that Fig. 2 ~ 5 provide, and shows that the sample prepared is the HfScMo of pure orthorhombic phase structure ₂vO ₁₂, in the XRD figure spectrum of the wherein 4# product that provides of Fig. 4, diffraction peak is relatively weak, shows that the sample prepared is the HfScMo of pure orthorhombic phase structure ₂vO ₁₂, but degree of crystallinity is slightly low, does not occur raw material peak but have part HfV in the XRD figure spectrum of the 1# product that Fig. 1 provides ₂o ₇characteristic peak, show prepare sample be HfScMo ₂vO ₁₂and HfV ₂o ₇two-phase mixtures.

embodiment 6 Performance Detection

Fig. 6 and Fig. 7 be respectively 3# product-130 ^oc ~ 400 ^oc and 30 DEG C ~ 500 ^oin the temperature range of C, relative length is with the change curve of probe temperature, and as can be seen from the figure, the relative length of 3# product reduces with the increase of temperature, shows that prepared material is negative thermal expansion ceramic material.-2.78 × 10 are about by calculating coefficient of linear expansion ^-6oc ^-1(-130 ~ 400 ^oand-3.10 × 10 C) ^-6oc ^-1(30 DEG C ~ 600 ^oc), illustrate that this stupalith has stable negative expansion character within the scope of-130 ~ 600 DEG C.

Raman spectrometer is observed this novel negative thermal expansion luminescent material, finds that this material can send white fluorescent under 325 nm wavelength lasers excite, photo as shown in Figure 8, illustrates that this material can be used as fluorescent material and uses, has engineer applied and be worth.The fluorescence spectrum figure of this material under 330 nm and 380nm wavelength light excite as shown in Figure 9.Fig. 9 shows, the wide spectral that this stupalith has from UV-light to red range is luminous, illustrates that it has application prospect in white light LED luminescent device.

Claims

1. a novel negative thermal expansion luminescent ceramic materials, its molecular formula is: HfScMo ₂vO ₁₂.

2. the solid state sintering synthetic method of novel negative thermal expansion luminescent ceramic materials described in claim 1, is characterized in that, comprise the following steps:

3. the solid state sintering synthetic method of novel negative thermal expansion luminescent ceramic materials according to claim 2, is characterized in that, in step (1), adds dehydrated alcohol and grind after raw material mixing.

4. the solid state sintering synthetic method of novel negative thermal expansion luminescent ceramic materials according to claim 3, it is characterized in that, in step (1), milling time is 2 h.