CN103964691B - A kind of fluorescent glass stupalith and preparation method thereof - Google Patents

Abstract

A kind of fluorescent glass stupalith, chemical formula is (Ca _0.99eu _0.01) ₃si ₂o ₇, be made up of initial material and rare earth additive, initial material is by SiO ₂and CaCO ₃composition, SiO in initial material total amount ₂mass percent be 80-90%, CaCO ₃for surplus; Rare earth additive is high purity Eu ₂o ₃; Described fluorescent glass stupalith is " core-shell structure copolymer " structure, and its center is Ca ₂siO ₄, shell is Eu ²⁺; Described fluorescent glass stupalith utilizes high enthalpy hydrogen plasma fast thawing technology to prepare.Advantage of the present invention is: 1) improve hydrogen plasma heat content, guarantee the thawing of material, namely keep the solid phase in the solid-liquid of high temperature to realize body crystalline substance; 2) utilize hydrogen plasma high reductibility, promote that rare earth ion Eu is reduced at a low price, to realize rare earth ion Eu ²⁺f → d wideband electronic transition characteristics launch, launch and there is the visible ray of characteristic feature.

Description

A kind of fluorescent glass stupalith and preparation method thereof

Technical field

The present invention relates to fluorescent glass stupalith and preparation method thereof.

Technical background

Optical functional glass or title photonic glass are class important materials in the fields such as information generation, display, transmission, storage, detection, develop into active illuminating (as laser glass) by the passive biography light in past, Application Areas relates to the key areas such as solid-state illumination packaged glass, photonic glass.These glass generally will mix rare earth ion, have the class line spectrum luminescence feature substantially identical with free ion, and rare earth ion needs to revert at a low price to realize broad-band illumination, and the ceramic of glass can strengthen crystal field impact, strengthens luminous efficiency.In existing glass-ceramic preparation, synthesis, processing technology, usually adopt method and the rare-earth sol-gel process of melt cooling-subsequent heat treatment crystallization.Consider from development manufacturing industry Key Common Technologies angle, adopt the glass melting of the melt cooling method of Simens technology, in 150 years since 1860, never reformed.Glass industry is big power consumer, and the thawing of raw material, clarifying treatment need to consume the long period, and industrial thawing furnace power consumption accounts for about 70% of glass production energy consumption; The lower concentration CO that melting process produces ₂, NO _xand SO _xbe not easy collection and treatment, contaminate environment.In addition, the advantages such as plasma technique is high with its temperature, ion kinetic energy is large, chemical property is active obtain a wide range of applications, wherein, plasma spraying coating technology has developed into the large-scale industrial application stage, relates to the broad areas such as thermal boundary, wear-and corrosion-resistant, photochemical catalysis, biology of metal, pottery, matrix material.

Plasma fast thawing technology is utilized to manufacture the work of glass, start recently studies have reported that, such as, the work of Watanabe in thermal plasma fast thawing glass of the Tokyo Institute of Technology, they have studied the fast melt of material particles in flight course, the vitrifying rule that spray into, think there is uniform composition, the thawing time sharply shortens, the remarkable advantage such as energy-conservation, but flight particles fuse is insufficient, enthalpy is large not, vitrifying does not allow manageable problem to need to solve; The domestic report also having the particle flight process utilizing plasma technology to manufacture glass specially, such as, TiA1 ₆v ₄aP40 glass ceramic coating prepared by matrix.The control of the plasma fast thawing behavior of material particles in flight course is key issue, if the melting of material particles external portion is recurrent phenomenon.

In the fluorescent glass exploration work adopting melt cooling method to carry out, have selected the CaO-SiO of Eu ion activation ₂glass system.At CaO-SiO ₂in system, to the Ca that divalent europium activates ₂siO ₄transmitting green light particle fluorescence body, Ca ₃si ₂o ₇launch orange red light, royal purple optical excitation mixed phase can produce white light.Usually, luminescent glass ceramic needs crystallization from homogeneous amorphous glass, Surface Crystallization pattern is in the majority, body crystallization needs to realize by adding nucleating agent induction crystallization, but additional nucleator absorbs incident photon energy possibly, by the mechanism such as absorption, reflection, self lattice resonance, phase boundary energy dissipation, effective luminescence center transition radiation is not affected, causes the reduction of luminous efficiency.Therefore needing to find does not need external Nucleating Agent and the luminescent glass ceramic processing technology of preparing with body crystallization.There is feature very much, by CaO-SiO ₂binary phase diagram is known, when temperature continues to raise, and single-phase Ca ₂siO ₄molten brilliant reaction will be there is and generate Silicon-rich liquid phase L+ crystalline phase Ca ₂siO ₄.Can infer thus, according to metering than being (Ca _2.99eu _0.01) ₃si ₂o ₇powder raw material under protection of reducing atmosphere, be melted to this solid-liquid two-phase region quenching and get off, will directly obtain containing Ca ₂siO ₄: Eu ²⁺the luminescent glass ceramic of crystalline phase, is namely distributed with Ceramic Luminescence particle in glass.This process, adopts the method for traditional melt cooling-subsequent heat treatment crystallization to be difficult to realize, needs to find new technique means.

Plasma fast thawing pottery and During Vitrification in vitro according to be the particle flight stage particle-plasma between interaction, therefore can condensed go out the differentiation physical model of a single grain matter, feed particles is described, physical and chemical changes that plasma area, flight, cooling stages stand; Although developed some fast thawing on-line monitorings, the understanding of article on plasma fast thawing unit details has still been limited to " black box " research mode more, and rare earth ion meticulously can indicate procedural information sensitively as light probe.About plasma heat content problem, in order to improve plasma heat enthalpy value, usually can at carrier gas (Ar or N ₂) in be mixed into a small amount of hydrogen (H of appropriate volume ratio ₂) or other fuel (such as propane), object is originally mainly in order to prevent particles fuse insufficient.After adding a small amount of rare earth ion, can impel and be reduced into rare earth ion at a low price while of these reducing gass, the glass be processed under light stimulus, can launch the visible ray with characteristic feature.About the valence state problem of plasma fusion cast glass intermediate ion, Muscovite Bessmertnyi etc. observe appraising at the current rate in Cr, Ti, Fe oxide plasma, find that wherein part is reduced.The valence state problem of rare earth ion during plasma fast thawing glass, does not see so far and has been report.

Summary of the invention

The object of the invention is for above-mentioned existing problems and technical Analysis, a kind of fluorescent glass stupalith and preparation method thereof is provided, this preparation method can improve plasma heat content, guarantees the thawing of material, or keeps the solid phase in the solid-liquid of high temperature to realize body crystalline substance; Hydrogen is reduced into rare earth ion Eu at a low price, to realize rare earth ion Eu ²⁺f → d wideband electronic transition characteristics launch.

Technical scheme of the present invention:

A kind of fluorescent glass stupalith, chemical formula is (Ca _0.99eu _0.01) ₃si ₂o ₇, be made up of initial material and rare earth additive, initial material is by SiO ₂and CaCO ₃composition, SiO in initial material total amount ₂mass percent be 80-90%, CaCO ₃for surplus; Rare earth additive is the Eu of purity 99.5-99.99% ₂o ₃, Eu ₂o ₃interpolation quality be the 1-5% of initial material; Described fluorescent glass stupalith is " core-shell structure copolymer " structure, and its center is Ca ₂siO ₄, shell is Eu ²⁺, nuclear diameter is 200 nanometer-5 microns, shell diameter is 10 microns.

A preparation method for described fluorescent glass stupalith, utilize high enthalpy hydrogen plasma fast thawing technology to prepare, step is as follows:

1) preparation of complex sol particle

By SiO ₂, CaCO ₃with Eu (NO ₃) ₃prepare according to the stoichiometric ratio of fluorescent glass stupalith composition, obtain complex sol powder, then send in spraying equipment, obtain the xerogel discrete particles of high-specific surface area through spraying;

2) plasma fast thawing-thermal treatment

By above-mentioned gel particle under reducing gas protection, utilize the plasma fast thawing technology of high hydrogen enthalpy, make the uniform composition of glass and rare earth ion is fully reduced, melt so far solid-liquid two-phase region, obtain containing Ca after quenching ₂siO ₄: Eu ²⁺the glass-ceramic light-emitting particles fluorescent material of crystalline phase, processing condition are: temperature of fusion is 560-2860 DEG C, powder sending quantity is 80-140g/min, reducing gas is the gas mixture of argon gas and hydrogen, in gas mixture, the mass percent of hydrogen is 5-10%, reducing gas utilizes 80kw high energy plasma spray gun to add, and flame passes Flow Velocity is less than 1000m/s, and the flight velocity of melting powder is 180-260m/s;

The hydrogen flame that above-mentioned glass-ceramic luminescent material sprays through too high enthalpy hydrogen plasma fast thawing is heated to rapidly 1300 DEG C, air cooling 3h again, then the glass-ceramic luminescent material powder of burning till and ammonium chloride and carbon dust are fully mixed to get mixture, wherein ammonium chloride quality is 3% of glass-ceramic luminescent material powder quality, carbon dust quality is the 3-10% of glass-ceramic luminescent material powder quality, mixture is heated to 1300 DEG C of insulation 6h, the mass percent passing into hydrogen is the argon of 5%-hydrogen gas mixture, to make EU ³⁺fully also fast transition is EU ²⁺, being then heated 1550 DEG C, when being incubated 0.5h, after being cooled to room temperature, obtaining green-emitting phosphor Ca ₂siO ₄: Eu ²⁺glass-ceramic light-emitting particles, when being incubated 1h, obtains red-emitting phosphors Ca after being cooled to room temperature ₃si ₂o ₇: Eu ²⁺glass-ceramic light-emitting particles;

3) machine-shaping

According to the shape of required fluorescent glass, above-mentioned glass-ceramic light-emitting particles is sprayed in different moulds and carries out air cooling to make chunk glass shaping, after cutting polishing processing, required fluorescent glass can be obtained.

Advantage of the present invention is: 1) improve hydrogen plasma heat content, guarantee the thawing of material, namely keep the solid phase in the solid-liquid of high temperature to realize body crystalline substance; 2) utilize hydrogen plasma high reductibility, promote that rare earth ion Eu is reduced at a low price, to realize rare earth ion Eu ²⁺f → d wideband electronic transition characteristics launch, launch and there is the visible ray of characteristic feature.

Accompanying drawing explanation

Fig. 1 is fluorescent glass stupalith " core-shell structure copolymer " structural representation, in figure: 1. polycrystal core, 2. noncrystal shell.

Fig. 2 is the Technology Roadmap of this fluorescent glass stupalith preparation method.

Fig. 3 is with the standby Eu doping CaO-SiO of melt cooling legal system ₂the scanning electron microscope image of system luminescent glass ceramic sample (1550 DEG C-0.5 hour), wherein (a) figure shows: be dispersed with the spheroidal particle that a large amount of mean diameter is 30 microns on the glass substrate, (b) figure shows: around spheroidal particle, occurred that a large amount of mean sizess is the platy shaped particle of hundreds of nanometer.

Embodiment

Describe in detail below in conjunction with the manufacturing process of accompanying drawing to mixed crystal phosphor glass pottery of the present invention.

Embodiment:

A kind of fluorescent glass stupalith, chemical formula is (Ca _0.99eu _0.01) ₃si ₂o ₇, be made up of initial material and rare earth additive, initial material is by SiO ₂and CaCO ₃composition, SiO in initial material total amount ₂mass percent be 85%, CaCO ₃for surplus; Rare earth additive is the Eu of purity 99.5% ₂o ₃, Eu ₂o ₃interpolation quality be 3% of initial material; Described fluorescent glass stupalith is " core-shell structure copolymer " structure, and as shown in Figure 1, its center 1 is Ca ₂siO ₄, shell 2 is Eu ²⁺, nuclear diameter is 5 microns, shell diameter is 10 microns.

The preparation method of described fluorescent glass stupalith, utilize high enthalpy hydrogen plasma fast thawing technology to prepare, step is as follows:

1) preparation of complex sol particle

By SiO ₂, CaCO ₃with Eu (NO ₃) ₃prepare according to the stoichiometric ratio of fluorescent glass stupalith composition, obtain complex sol powder, then send in spraying equipment, obtain the xerogel discrete particles of high-specific surface area through spraying;

2) plasma fast thawing-thermal treatment

By above-mentioned gel particle under reducing gas protection, utilize the plasma fast thawing technology of high hydrogen enthalpy, make the uniform composition of glass and rare earth ion is fully reduced, melt so far solid-liquid two-phase region, obtain containing Ca after quenching ₂siO ₄: Eu ²⁺the glass-ceramic light-emitting particles fluorescent material of crystalline phase, processing condition are: temperature of fusion is 1700 DEG C, powder sending quantity is 120g/min, reducing gas is the gas mixture of argon gas and hydrogen, in gas mixture, the mass percent of hydrogen is 5%, reducing gas utilizes 80kw high energy plasma spray gun to add, and flame passes Flow Velocity is less than 1000m/s, and the flight velocity of melting powder is 210m/s;

The hydrogen flame that above-mentioned glass-ceramic luminescent material sprays through too high enthalpy hydrogen plasma fast thawing is heated to rapidly 1300 DEG C, air cooling 3h again, then the glass-ceramic luminescent material powder of burning till and ammonium chloride and carbon dust are fully mixed to get mixture, wherein ammonium chloride quality is 3% of glass-ceramic luminescent material powder quality, carbon dust quality is 7% of glass-ceramic luminescent material powder quality, mixture is heated to 1300 DEG C of insulation 6h, the mass percent passing into hydrogen is the argon of 5%-hydrogen gas mixture, to make EU ³⁺fully also fast transition is EU ²⁺, being then heated 1550 DEG C, when being incubated 0.5h, after being cooled to room temperature, obtaining green-emitting phosphor Ca ₂siO ₄: Eu ²⁺glass-ceramic light-emitting particles, when being incubated 1h, obtains red-emitting phosphors Ca after being cooled to room temperature ₃si ₂o ₇: Eu ²⁺glass-ceramic light-emitting particles;

3) machine-shaping

According to the shape of required fluorescent glass, above-mentioned glass-ceramic light-emitting particles is sprayed in different moulds and carries out air cooling to make chunk glass shaping, after cutting polishing processing, required fluorescent glass can be obtained.

Fig. 3 is with the standby Eu doping CaO-SiO of melt cooling legal system ₂the scanning electron microscope image of system luminescent glass ceramic sample (1550 DEG C-0.5 hour), wherein (a) figure shows: be dispersed with the spheroidal particle that a large amount of mean diameter is 30 microns on the glass substrate, (b) figure shows: around spheroidal particle, occurred that a large amount of mean sizess is the platy shaped particle of hundreds of nanometer.

Analysis on Mechanism:

1) glass-ceramic Composition Design

According to (Ca _0.99eu _0.01) ₃si ₂o ₇metering ratio, directly can obtain Ca at solid-liquid two-phase region melt quenching ₂siO ₄: Eu ²⁺body mixed crystal glass-ceramic twinkler, different in two-phase region soaking time, β-Ca wherein can be controlled ₂siO ₄the size of spheroidal particle and luminosity.

2) high enthalpy hydrogen plasma stream is to the fusing of single grain matter and vitrifying mechanism

Control the hydrogen concentration in carrier gas; by spraying into the analysis of experiments test of the composition of glass (particle or block) after material particles and fast thawing, degree of crystallinity, pattern, rare earth ion valence state and spectral quality; according to the granular model of figure mono-, disclose the physical chemistry rule such as heat transfer, mass transfer, reaction, phase transformation, melting, rapid cooling, vitrifying Crystal Evolution occurred between gas mixture plasma and particle.

3) corresponding relation between the structure of hydrogen plasma fast thawing Optimizing Technical and fluorescent glass, rare earth ion valence state.By the performance test results of fluorescent glass sample obtained, association material particles characteristic, relation between glass-ceramic structure and plasma fast thawing optimisation technique parameter.

Conventional method of analysis:

Dsc (DifferentialScanningCalorimetry) is adopted to measure material according to design mix in advance, obtain typical DSC melting curve, for the time, integration is carried out to whole DSC curve peak, just can obtain the heat content of material, and provide the phase transformation-temperature relation of material, be used for instructing plasma H ₂the amount of allocating into and the setting of parameter.Integration type is as follows:

$\mathrm{\ΔH}=\∫\frac{\mathrm{dH}}{\mathrm{dt}}\·\mathrm{dt}$

Granule-morphology in colloidal sol atomization-sintering process is developed, according to the gas set up---solid-gas sol is theoretical, according to the formation physical chemical mechanism of the Single pellet model of the model analyzing " atomizing droplet forms a spheroidal particle " of Fig. 1.

The glass sample that article on plasma fast thawing is obtained, thermal treatment can investigate crystal effect further.Carry out the thermal analyses (DTA) of different scanning rates and step-length, determine glass transition temp (Tg), crystallization peak temperature (Tp), with the Kissinger formulae discovery crystallization activation energy of classics, crystallization mode (surface, body) is judged by Ozawa formulae discovery Avrami parameter; On this basis, to the glass of special component, carry out meticulous thermal treatment.To valence state and the luminosity of rare earth ion, with test absorb, the position of excitation and emission spectra, shape and intensity evaluates, such as, Eu ²⁺wideband spectrum, Eu ³⁺sharp line spectrum, Eu ⁰/ Eu ⁺not luminous.Based on granular model, with electron energy loss spectroscopy (EELS) (EELS) the analytical chemistry constituent content of the spatial discrimination of the EDX in TEM and scanning transmission electron microscope (STEM).

Claims (1)

1. a preparation method for fluorescent glass stupalith, the chemical formula of described fluorescent glass stupalith is (Ca _0.99eu _0.01) ₃si ₂o ₇, be made up of initial material and rare earth additive, initial material is by SiO ₂and CaCO ₃composition, SiO in initial material total amount ₂mass percent be 80-90%, CaCO ₃for surplus; Rare earth additive is the Eu of purity 99.5-99.99% ₂o ₃, Eu ₂o ₃interpolation quality be the 1-5% of initial material; Described fluorescent glass stupalith is " core-shell structure copolymer " structure, and its center is Ca ₂siO ₄, shell is Eu ²⁺, nuclear diameter is 200 nanometer-5 microns, shell diameter is 10 microns,

It is characterized in that utilizing high enthalpy hydrogen plasma fast thawing technology to prepare, step is as follows:

1) preparation of complex sol particle

By SiO ₂, CaCO ₃with Eu (NO ₃) ₃prepare according to the stoichiometric ratio of fluorescent glass stupalith composition, obtain complex sol powder, then send in spraying equipment, obtain the xerogel discrete particles of high-specific surface area through spraying;

2) plasma fast thawing-thermal treatment

By above-mentioned xerogel discrete particles under reducing gas protection, utilize the plasma fast thawing technology of high hydrogen enthalpy, make the uniform composition of glass and rare earth ion is fully reduced, melt so far solid-liquid two-phase region, obtain containing Ca after quenching ₂siO ₄: Eu ²⁺the glass-ceramic light-emitting particles fluorescent material of crystalline phase, processing condition are: temperature of fusion is 560-2860 DEG C, powder sending quantity is 80-140g/min, reducing gas is the gas mixture of argon gas and hydrogen, in gas mixture, the mass percent of hydrogen is 5-10%, reducing gas utilizes 80kw high energy plasma spray gun to add, and flame passes Flow Velocity is less than 1000m/s, and the flight velocity of melting powder is 180-260m/s;

The hydrogen flame that above-mentioned glass-ceramic luminescent material sprays through too high enthalpy hydrogen plasma fast thawing is heated to rapidly 1300 DEG C, air cooling 3h again, then the glass-ceramic luminescent material powder of burning till and ammonium chloride and carbon dust are fully mixed to get mixture, wherein ammonium chloride quality is 3% of glass-ceramic luminescent material powder quality, carbon dust quality is the 3-10% of glass-ceramic luminescent material powder quality, mixture is heated to 1300 DEG C of insulation 6h, the mass percent passing into hydrogen is the argon of 5%-hydrogen gas mixture, to make Eu ³⁺fully also fast transition is Eu ²⁺, being then heated 1550 DEG C, when being incubated 0.5h, after being cooled to room temperature, obtaining green-emitting phosphor Ca ₂siO ₄: Eu ²⁺glass-ceramic light-emitting particles, when being incubated 1h, obtains red-emitting phosphors Ca after being cooled to room temperature ₃si ₂o ₇: Eu ²⁺glass-ceramic light-emitting particles;

3) machine-shaping

According to the shape of required fluorescent glass, above-mentioned glass-ceramic light-emitting particles is sprayed in different moulds and carries out air cooling to make chunk glass shaping, after cutting polishing processing, required fluorescent glass can be obtained.