CN112340712B - Nitrogen oxide elastic stress luminescent material and preparation method thereof - Google Patents

Nitrogen oxide elastic stress luminescent material and preparation method thereof Download PDF

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CN112340712B
CN112340712B CN202011242619.5A CN202011242619A CN112340712B CN 112340712 B CN112340712 B CN 112340712B CN 202011242619 A CN202011242619 A CN 202011242619A CN 112340712 B CN112340712 B CN 112340712B
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luminescent material
nitrogen oxide
stress luminescent
elastic stress
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庄逸熙
李武辉
林飞燕
陈昌健
周天亮
解荣军
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Xiamen University
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Abstract

Nitrogen oxide elastic stress luminescent material and preparation thereofMethod of forming said oxynitride elastic stress luminescent material Y2‑ xSi3O3N4:Rex(Re ═ Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, or Yb), where x represents the mole percent content, 0<x<0.5; the preparation method of the nitrogen oxide elastic stress luminescent material comprises the following steps: (1) respectively weighing a certain amount of raw materials according to the element molar ratio; (2) grinding the weighed raw materials uniformly, and roasting in a protective atmosphere; (3) and taking out the roasted sample, and grinding to obtain the nitrogen oxide elastic stress luminescent material. The elastic stress luminescent material has excellent stress luminescent property, adjustable luminescent wavelength and high luminescent efficiency, and has potential application value in the fields of structural flaw detection, electronic signature systems, electronic skins and the like, which relate to dynamic mechanical force change monitoring and the like.

Description

Nitrogen oxide elastic stress luminescent material and preparation method thereof
Technical Field
The invention relates to the field of inorganic luminescent materials, in particular to a nitrogen oxide elastic stress luminescent material and a preparation method thereof.
Background
The Mechanoluminescence (ML) refers to a phenomenon in which luminescence occurs by using a mechanical force as an excitation source, and a material having a stress luminescence property is called a stressor. The stress luminescent materials are classified into destructive stress luminescent materials and non-destructive stress luminescent materials, and the non-destructive stress luminescent materials are further classified into elastic stress luminescent materials that can be self-recovered and plastic stress luminescent materials that cannot be self-recovered. The unique energy conversion mode of the stress luminescent material makes the stress luminescent material have wide application prospect.
The stress luminescent material has been widely researched due to its important application potential in the fields of nondestructive inspection, repeatable real-time stress detection and the like. A great deal of research work is carried out on the light-emitting mechanism, the material composition and the structural characteristics of the material, and a plurality of stress light-emitting materials are developed.However, most of the stress luminescent materials reported at present are destructive materials, and are difficult to be widely applied in practical scenes. At present, all stress luminescent materials with obvious application potential are elastic stress luminescent materials, and mainly comprise the following materials: SrAl2O4:Eu2+(Green), ZnS: Mn2+(yellow light); ZnS: Cu (blue-green), CaZnOS: Mn2+(Red light), etc. The luminescent wavelength of the materials is limited to visible wave bands, and the development of luminescent materials with longer wave bands, especially near infrared stress has important significance for the application of the luminescent materials in stress sensing, wearable equipment and the like in organisms. Meanwhile, the chemical stability of the materials is generally poor, and a new high-stability elastic stress luminescent material system which can be applied to high-temperature and high-humidity environments is urgently needed to be developed.
Currently, there are many problems in the research of elastic stress luminescent materials: (1) the variety of elastic stress luminescent materials which do not need to be pre-excited is less; (2) the known elastic stress luminescent material has low luminescent intensity and is difficult to meet the requirements of practical application; (3) the light emitting mechanism of the elastic stress luminescent material is not clearly researched, and the development and design of the novel elastic stress luminescent material still have challenges.
Disclosure of Invention
The present invention is directed to solving the above problems in the prior art, and provides a nitrogen oxide elastic stress luminescent material and a preparation method thereof.
In order to achieve the purpose, the invention adopts the following technical scheme:
the chemical general formula of the nitrogen oxide elastic stress luminescent material is Y2-xSi3O3N4:RexWherein Re comprises one or more of rare earth ions Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb, x represents the mole percentage content, 0<x<0.5。
The crystal structure of the nitrogen oxide elastic stress luminescent material belongs to a tetragonal system, and the space group is
Figure BDA0002768469570000021
In the composition of the nitrogen oxide elastic stress luminescent material, x is more than 0 and less than 0.05.
A preparation method of nitrogen oxide elastic stress luminescent material comprises the following steps:
1) the nitrogen oxide elastic stress luminescent material Y2-xSi3O3N4:RexIn the method, Y adopts oxide or nitride thereof as raw material, Si adopts oxide or nitride thereof as raw material, doped rare earth ions adopt oxide or nitride thereof as raw material, and CaF is adopted2、BaF2Or SrF2As a fluxing agent, weighing the raw materials of each element according to the stoichiometric ratio, and grinding for a period of time until the raw materials are uniformly mixed;
2) putting the raw materials ground and uniformly mixed in the step (1) into a tubular furnace, heating to a certain temperature, preserving heat for a certain time under a protective atmosphere, and naturally cooling to room temperature after heat preservation is finished;
3) grinding the powder sintered in the step (2) to obtain the nitrogen oxide elastic stress luminescent material Y2- xSi3O3N4:Rex。
In the step (2), the certain temperature is 1550-1650 ℃, and the certain time is 7-12 h.
In the invention, Y adopts the oxide thereof as the raw material; si adopts nitride thereof as a raw material; the doped rare earth ions are prepared from oxides of the rare earth ions.
In the step (1), the fluxing agent adopted is BaF2(ii) a In the step (2), the protective atmosphere used can be a nitrogen-hydrogen mixed gas atmosphere or a pure nitrogen atmosphere.
The application of nitrogen oxide elastic stress luminescent material is characterized by that it does not need the light with short wavelength to make pre-excitation energy storage, but utilizes the direct mechanical force to produce stress luminescence.
The powder sample of the nitrogen oxide elastic stress luminescent material or the film sample made of the nitrogen oxide elastic stress luminescent material powder and the high polymer material generates stress luminescence in an elastic deformation range by loading mechanical force.
The mechanical force loaded by the oxynitride elastic stress luminescent material includes but is not limited to friction, stretching, ultrasound, impact, bending, torsion and the like.
Compared with the prior art, the technical scheme of the invention has the following beneficial effects:
1. the material is prepared by adopting a traditional high-temperature solid-phase reaction method, the reaction condition is controllable, the equipment is simple, the cost is low, the environment is friendly, and no harmful substance is generated in the preparation process.
2. The material of the invention has good chemical stability and high luminous efficiency.
3. The material of the invention can realize stress luminescence with adjustable luminescence wavelength and color by doping different rare earth ions as luminescence centers.
4. The material of the invention has adjustable light-emitting wavelength and high light-emitting efficiency, and has potential application value in the fields of structural flaw detection, electronic signature systems, electronic skins and the like, which relate to dynamic mechanical force change monitoring and the like.
Drawings
FIG. 1 shows X-ray diffraction spectra of sample powders prepared in examples 1 to 3.
Fig. 2 is an emission spectrum of a sample prepared in example 1.
Fig. 3 is an emission spectrum of a sample prepared in example 2.
Fig. 4 is an emission spectrum of the sample prepared in example 3.
Fig. 5 is a triboluminescence spectrum of the sample prepared in example 1.
Fig. 6 is a triboluminescence spectrum of the sample prepared in example 2.
Fig. 7 is a triboluminescence spectrum of the sample prepared in example 3.
Fig. 8 is a triboluminescence spectrum of the sample prepared in example 4.
Fig. 9 is a triboluminescence spectrum of the sample prepared in example 5.
Detailed Description
In order to make the technical problems, technical solutions and advantageous effects of the present invention clearer and clearer, the present invention is further described in detail below with reference to the accompanying drawings and embodiments.
Selecting yttrium oxide, silicon nitride and rare earth ion oxide as raw materials, adding a proper amount of barium fluoride as a fluxing agent, weighing the raw materials according to the molar ratio of each element (specifically shown in table 1), putting the raw materials into an agate mortar for grinding, uniformly mixing, taking a proper amount of sample, putting the sample into a cylindrical alumina crucible, putting the cylindrical crucible into a corundum boat, putting the corundum boat into a tubular furnace, and putting the corundum boat into the tubular furnace in an N (nitrogen) furnace 290％-H2Heating to 1600 ℃ in a 10% nitrogen-hydrogen reducing atmosphere, preserving heat for 7h, and naturally cooling to room temperature after heat preservation. And grinding the sintered sample into powder with uniform size to obtain the oxynitride-based stress luminescent powder.
TABLE 1 sample proportioning for examples 1-5
Figure BDA0002768469570000031
FIG. 1 is an X-ray diffraction pattern of samples prepared in examples 1 to 3, wherein the spectral lines are measured by a Bruker d8-advance bruker X-ray diffractometer with a test voltage of 40kV and a test current of 40mA, and Cu-Ka rays with a wavelength of 40kV and a wavelength of 40mA are selected
Figure BDA0002768469570000032
X-ray diffraction analysis shows that calcining the sample at 1600 ℃ for 7h can obtain Y2Si3O3N4Pure phase, belonging to tetragonal system, the doping of rare earth ions Yb, Ce and Tb does not affect the formation of crystal phase, and other mixed phases are not observed.
FIG. 2 is an emission spectrum of the sample prepared in example 1, measured using Edinburgh instruments FL980 steady-state and transient-state luminescence spectrometer with a xenon lamp as excitation light source, with an integration time of 0.2 seconds and a step frequency of 1 nm. Sample Y from example 1, excited by 335nm light1.99Si3O3N4:Yb0.01Has linear near infrared emission with a luminous peak of 980nm and is attributed to Yb3+Electronic slave2F5/2To2F7/2Is detected.
FIG. 3 is an emission spectrum of a sample prepared in example 2, sample Y1.98Si3O3N4:Yb0.02Linear near infrared emission with an emission peak at 980nm and belonging to Yb3+Electronic slave2F5/2To2F7/2Is detected.
FIG. 4 is an emission spectrum of a sample prepared in example 3, sample Y1.96Si3O3N4:Ce0.02-Tb0.02The 484nm linewidth peak emission luminescence comes from Ce3+The linear emission of electrons from 5 d-4 f at 543nm, 585nm and 625nm is derived from Tb3+Is5D4→7F5、5D4→7F4、5D4→7F3Is detected.
Fig. 5 is a triboluminescence spectrum of a sample prepared in example 1, a powder sample was loaded in a mortar, the sample was rubbed using a glass rod, and simultaneously light emitted by the sample friction was collected using a marine optical fiber spectrometer QE-Pro, and an integration time for collecting data was 1 second. As shown in fig. 5, the sample exhibited stress luminescence whose triboluminescence spectrum and emission spectrum substantially remained the same.
Fig. 6 is a triboluminescence spectrum of a sample prepared in example 2, and as shown in fig. 6, the sample exhibited stress luminescence whose triboluminescence spectrum and emission spectrum substantially remained the same.
Fig. 7 is a triboluminescence spectrum of a sample prepared in example 3, and as shown in fig. 7, the sample exhibited stress luminescence whose triboluminescence spectrum and emission spectrum substantially remained the same.
FIG. 8 is a triboluminescence spectrum of a sample prepared in example 4, which sample exhibits stress luminescence, sample Y, as shown in FIG. 81.96Si3O3N4:Ce0.04The 484nm linewidth peak emission luminescence comes from Ce3+Transition of electron from 5d → 4 f.
FIG. 9 is a triboluminescence spectrum of a sample prepared in example 5, which sample showed the response, as shown in FIG. 9Mechanoluminescence, sample Y1.956Si3O3N4:Ce0.04-Pr0.004The 484nm linewidth peak emission luminescence comes from Ce3+Transition of electron from 5d → 4 f. The 528nm, 544nm, 559nm and 666nm linear emission light of the material comes from Pr3+Electronic slave3P0→3H5And3P0→3F2is detected.

Claims (5)

1. The application of the nitrogen oxide elastic stress luminescent material in the field of dynamic mechanical force change monitoring is characterized in that: stress luminescence can be generated by directly applying stress to the material without the need of pre-irradiation of ultraviolet light or visible light, and the chemical general formula of the nitrogen oxide elastic stress luminescent material is Y2-xSi3O3N4:RexWherein Re comprises one or more of rare earth ions Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb, x represents the mole percentage content, and 0< x < 0.5。
2. The use of the oxynitride elastic stress luminescent material of claim 1 in the dynamic mechanical force variation monitoring field, wherein: in the composition of the nitrogen oxide elastic stress luminescent material, x is more than 0 and less than 0.05.
3. The application of the nitrogen oxide elastic stress luminescent material in the field of dynamic mechanical force change monitoring as claimed in claim 1, wherein: the crystal structure of the nitrogen oxide elastic stress luminescent material belongs to a tetragonal system, and the space group is P
Figure DEST_PATH_IMAGE001
1m。
4. The application of the nitrogen oxide elastic stress luminescent material in the field of dynamic mechanical force change monitoring as claimed in claim 1, wherein stress is applied to the nitrogen oxide elastic stress luminescent material powder without prior ultraviolet light or visible light irradiation, or stress is applied to a film or a cylinder prepared by mixing the nitrogen oxide elastic stress luminescent material powder with an elastic polymer material, and stress luminescence occurs within the elastic limit of the material.
5. The use of a luminescent material according to claim 1 or 4 for detecting dynamic mechanical stress, wherein the applied stress comprises friction, compression, tension, bending, impact, torsion, ultrasound.
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CN103468258A (en) * 2013-09-05 2013-12-25 青岛大学 Red high-brightness elastic stress luminescent material and preparation method thereof
CN108410464A (en) * 2018-03-01 2018-08-17 渤海大学 A kind of sulphur lanthana fluorescent powder and preparation method thereof of transmitting near infrared light
CN110628423A (en) * 2019-10-09 2019-12-31 厦门大学 Oxysulfide elastic stress luminescent material and preparation method thereof

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008248052A (en) * 2007-03-30 2008-10-16 National Institute Of Advanced Industrial & Technology Stress-induced light-emitting material for emitting ultraviolet ray, its manufacturing method, and its utilization
CN103468258A (en) * 2013-09-05 2013-12-25 青岛大学 Red high-brightness elastic stress luminescent material and preparation method thereof
CN108410464A (en) * 2018-03-01 2018-08-17 渤海大学 A kind of sulphur lanthana fluorescent powder and preparation method thereof of transmitting near infrared light
CN110628423A (en) * 2019-10-09 2019-12-31 厦门大学 Oxysulfide elastic stress luminescent material and preparation method thereof

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