阅读说明：本技术 一种LiXSe2多晶化合物与单晶体的合成方法 (A kind of LiXSe2The synthetic method of polycrystalline compounds and monocrystal ) 是由 徐亚东 郭力健 薛望祺 肖宝 介万奇 于 2019-10-08 设计创作，主要内容包括：本发明涉及一种LiXSe_2多晶化合物与单晶体的合成方法,将Li、In、Ga、Se几种单质装入内层坩埚与石英坩埚中并真空封装,装入摇摆炉中,在LiXSe_2化合物熔点以上,保温、摇摆,随后冷却到室温。得到的LiXSe_2(X＝In/Ga/In_yGa_(1-y))化合物符合其化学计量比。通过控制温度及采用梯度温度保温,在Li、Se较低的蒸汽压下,使Li、In、Ga和Se四种单质在Li、Se熔点附近发生化合反应,得到Li_2Se、In_xSe_y和Ga_xSe_y等化合物,以固定Li与Se的化学活性,从而减少Li与Se成分的损失,利用该方法得到的LiXSe_2(X＝In/Ga/In_yGa_(1-y))多晶原料生长得到的LiXSe_2(X＝In/Ga/In_yGa_(1-y))单晶体的化学成分对化学计量比的偏离可以控制在5％以内。(The present invention relates to a kind of LiXSe 2 Several simple substance of Li, In, Ga, Se are fitted into inner crucible and silica crucible simultaneously Vacuum Package, are fitted into rocking furnace, in LiXSe by the synthetic method of polycrystalline compounds and monocrystal 2 It more than melting point compound, keeps the temperature, wave, be subsequently cooled to room temperature.Obtained LiXSe 2 (X=In/Ga/In y Ga 1‑y ) compound meets its stoichiometric ratio.It is kept the temperature by control temperature and using gradient temperature, under the lower vapour pressure of Li, Se, makes tetra- kinds of simple substance of Li, In, Ga and Se that combination reaction occur near Li, Se fusing point, obtain Li 2 Se、In x Se y And Ga x Se y Equal compounds, to fix the chemical activity of Li and Se, so that the loss of Li Yu Se ingredient are reduced, the LiXSe obtained using this method 2 (X=In/Ga/In y Ga 1‑y ) LiXSe that grows of polycrystal raw material 2 (X=In/Ga/In y Ga 1‑y ) chemical component of monocrystal can control within 5% the deviation of stoichiometric ratio.)

1. a kind of LiXSe₂The synthetic method of polycrystalline compounds and monocrystal, wherein X=In/Ga/In_yGa_1-y；It is characterized in that step It is rapid as follows:

Step 1: crucible being pre-processed, under vacuum conditions, acetone or methane organic matter is pyrolyzed, passes through chemical vapor deposition One layer of carbon film is deposited on the inner wall of quartz crucible of method after the drying；

Step 2: selection melting element simple substance scheme are as follows: tri- kinds of element lists of tri- kinds of element simple substances of Li, In and Se or Li, Ga and Se Tetra- kinds of element simple substances of matter or Li, In, Ga, Se；

When using tri- kinds of element simple substances of Li, In and Se or tri- kinds of element simple substances of Li, Ga and Se, according to stoichiometric ratio 1:1: When 2 proportion, it is further added by 1~3% Li and 1~3% Se, is put into inner crucible together；

When using tetra- kinds of element simple substances of Li, In, Ga, Se, when being added according to stoichiometric ratio 1:y:1-y:2, increase by 1~3% Li and 1~3% Se, be put into inner crucible together；The y is the arbitrary number between 0~1；

Step 3: inner crucible covers plug, is enclosed in raw material in one relatively closed space；

Step 4: being put into the silica crucible for having plated carbon film, be evacuated down to 10^-4-10^-6Pa, after sealing silica crucible using oxyhydrogen flame It is put into and waves in conjunction material furnace；

Step 5: 180 DEG C of fusing point for material furnace will be closed being warming up to the rate of 30-50 DEG C/h Li, then with the rate of 5~10 DEG C/h It is warming up to the fusing point of Se or more, then melts raw material all in 2~5h of the temperature；The fusing point temperatures above of the Se is 220℃-260℃；

Step 6: being then warming up to the reaction temperature of Li and In with the rate of 5~30 DEG C/h, and make in 2~15h of the temperature Simple substance raw material further sufficiently reacts；The reaction temperature of the Li and In is 450 DEG C -500 DEG C；It is described during incubation, open Rocking furnace comes into full contact with the raw material of melting, and chemical combination is more uniform；

Step 7: subsequent system is warming up to LiXSe with the rate of 50 DEG C/h₂On the fusing point of compound, 12~36h is kept the temperature；The X =In/Ga/In_yGa_1-y；The LiXSe₂The fusing point of compound is 915 DEG C~930 DEG C；It is described during incubation, unlatching is waved Furnace comes into full contact with the raw material of melting, and chemical combination is more uniform；

Step 8: after heat preservation, furnace cooling after cooling to 700 DEG C with the rate of 5-30 DEG C/h；

Step 9: LiXSe is taken out from crucible₂Polycrystal raw material is reloaded cleaned in advance and is plated using chemical vapour deposition technique In the silica crucible of good carbon film, and it is evacuated down to 10^-4-10^-6Pa seals silica crucible using oxyhydrogen flame；The X=In/Ga/ In_yGa_1-y。

Step 10: the double crucible systems of inner crucible-silica crucible after cooling are fitted into crystal growing furnace；

Step 11: crucible is initially located at the high-temperature region of the upper furnace of crystal growing furnace, improves the furnace temperature of crystal growing furnace, makes height The furnace temperature of warm area is 30 DEG C~50 DEG C higher than polycrystalline fusing point, is 945 DEG C~965 DEG C；After polycrystal raw material is sufficiently melted and is overheated, crucible Declined with the rate of 0.1mm/h~5mm/h, carries out crucible by the gradient zones 5 DEG C/cm~20 DEG C of temperature gradient/cm brilliant Body growth, after melt all passes through the solid-liquid interface of the temperature gradient zone of burner hearth, crystal growth terminates；Subsequent crystal growth Furnace cools to 600 DEG C with the speed of 2 DEG C/h, and furnace cooling is after then dropping to 250 DEG C with the speed of 5~15 DEG C/h to get arriving LiXSe₂Monocrystal, X=In/Ga/In_yGa_1-y。

2. LiXSe according to claim 1₂The synthetic method of polycrystalline compounds and monocrystal, it is characterised in that: the crucible It pre-processes: first using acetone soak to remove organic impurities the silica crucible of inner crucible and outer layer, impregnated with chloroazotic acid to go It except inorganic impurity, is then cleaned up, is dried with deionized water.

3. LiXSe according to claim 1₂The synthetic method of polycrystalline compounds and monocrystal, it is characterised in that: the internal layer Crucible is graphite crucible, PBN crucible or glass carbon crucible.

Technical field

The invention belongs to polycrystalline compounds and monocrystal synthetic method, are related to a kind of LiXSe₂Polycrystalline compounds and monocrystal Synthetic method, be related to nonlinear optics and neutron detection LiXSe₂(X=In/Ga/In_yGa_1-y) polycrystalline compounds and monocrystalline The preparation method of body.

Background technique

LiXSe₂(X=In/Ga/In_yGa_1-y) crystal is a kind of nonlinear optical crystal haveing excellent performance, based on its frequency multiplication, With the second nonlinear optics characteristic such as frequency, difference frequency, optical parametric oscillation, second harmonic generator, frequency converter, light can be made The device for non-linear optical such as parametric oscillator.In addition to this, due to⁶Li is very big to the capture cross-section of neutron, utilizes LiXSe₂(X= In/Ga/In_yGa_1-y) crystal can be prepared into neutron detector, in nuclear energy application, anti-terrorism, prevention of nuclear proliferation, high energy nuclear detection etc. Field has to be widely applied very much.

But preparation LiXSe₂(X=In/Ga/In_yGa_1-y) there is also many problems for crystal, since the chemical property of Li is living It sprinkles, is easy to react with silica crucible, while a large amount of Se can be lost during synthesis and single crystal preparation.Current method is logical It can often be added in advance certain excessive Li and Se in synthesised polycrystalline material, but obtained LiXSe₂(B=In/Ga/In_yGa_1-y) The stoichiometric ratio of the ingredient of monocrystal and its 1:1:2 there are certain deviation, wherein the bias of Li can achieve 25% with On.In view of the vapour pressure of Li and Se is continuously increased with the rising of temperature, it will lead to more Se gasifications under high temperature, simultaneously The Li to gasify under high temperature reacts more violent with quartz, and the vapor liquid equilibrium that will lead to Li is constantly broken, to pull Li's Vapor liquid equilibrium is mobile to gas direction.

It is also had been reported that in document at present and carries out conjunction material under low temperature, be warming up at the fusing point of Se (220 DEG C -240 DEG C) progress Heat preservation, progress Li are reacted with Ga's, are then kept the temperature at 500 DEG C, and carry out Se and Li and Ga reacts the steam for reducing Se Pressure.In patent application case " a method of synthesis LiXSe2 polycrystalline compounds and monocrystal " although in surveyed according to DSC heat analysis Examination, in Li, at the fusing point of Li (180 DEG C) are reacted with Se, provide that a kind of preparation temperature is lower, the simpler synthesis of process Technique.But making raw material all not enough fusings, Li, In, Ga and Se insufficient contact, especially Se react inadequate with Li simple substance Sufficiently, Li is being formed₂Se、In_xSe_yAnd Ga_xSe_yEqual compounds, the keys such as Li-Se, In-Se and Ga-Se of formation can not be effective Fixed Li and Se simple substance, the loss of Se and Li cannot get, so that the deviation of stoichiometric ratio cannot be reduced very well.

Summary of the invention

Technical problems to be solved

In order to avoid the shortcomings of the prior art, the present invention proposes a kind of synthesis LiXSe₂Polycrystalline compounds and monocrystal Method.Change original technology scheme and be brought rapidly up the technique for reacting raw material to 500 DEG C or more, when keeping raw material long at low temperature Between stop, occur combination reaction, to reduce the loss of Se and Li under high temperature, to more be met the LiXSe of stoichiometric ratio₂ (X=In/Ga/In_yGa_1-y) crystal, the program can be by the bias control of three kinds of ingredients within 5%.

Technical solution

A kind of LiXSe₂The synthetic method of polycrystalline compounds and monocrystal, wherein X=In/Ga/In_yGa_1-y；It is characterized in that Steps are as follows:

Step 1: crucible being pre-processed, under vacuum conditions, acetone or methane organic matter is pyrolyzed, passes through chemical gaseous phase One layer of carbon film is deposited on the inner wall of quartz crucible of sedimentation after the drying；

Step 2: selection melting element simple substance scheme are as follows: tri- kinds of members of tri- kinds of element simple substances of Li, In and Se or Li, Ga and Se Tetra- kinds of element simple substances of plain simple substance or Li, In, Ga, Se；

When using tri- kinds of element simple substances of Li, In and Se or tri- kinds of element simple substances of Li, Ga and Se, according to stoichiometric ratio When 1:1:2 is matched, it is further added by 1~3% Li and 1~3% Se, is put into inner crucible together；

When using tetra- kinds of element simple substances of Li, In, Ga, Se, when being added according to stoichiometric ratio 1:y:1-y:2, increase by 1~ The Se of 3% Li and 1~3%, is put into inner crucible together；The y is the arbitrary number between 0~1；

Step 3: inner crucible covers plug, is enclosed in raw material in one relatively closed space；

Step 4: being put into the silica crucible for having plated carbon film, be evacuated down to 10^-4-10^-6Pa seals quartz using oxyhydrogen flame It is put into and is waved in conjunction material furnace after crucible；

Step 5: 180 DEG C of fusing point for material furnace will be closed being warming up to the rate of 30-50 DEG C/h Li, then with 5~10 DEG C/h's Rate is warming up to the fusing point of Se or more, then melts raw material all in 2~5h of the temperature；It is more than the fusing point of the Se warm Degree is 220 DEG C -260 DEG C；

Step 6: be then warming up to the reaction temperature of Li and In with the rate of 5~30 DEG C/h, and the temperature 2~ 15h reacts simple substance raw material further sufficiently；The reaction temperature of the Li and In is 450 DEG C -500 DEG C；It is described during incubation, Rocking furnace is opened, comes into full contact with the raw material of melting, chemical combination is more uniform；

Step 7: subsequent system is warming up to LiXSe with the rate of 50 DEG C/h₂On the fusing point of compound, 12~36h is kept the temperature； The X=In/Ga/In_yGa_1-y；The LiXSe₂The fusing point of compound is 915 DEG C~930 DEG C；It is described during incubation, open Rocking furnace comes into full contact with the raw material of melting, and chemical combination is more uniform；

Step 8: after heat preservation, furnace cooling after cooling to 700 DEG C with the rate of 5-30 DEG C/h；

Step 9: LiXSe is taken out from crucible₂Polycrystal raw material reloads cleaned in advance and utilizes chemical vapor deposition Method has been plated in the silica crucible of carbon film, and is evacuated down to 10^-4-10^-6Pa seals silica crucible using oxyhydrogen flame；The X=In/ Ga/In_yGa_1-y。

Step 10: the double crucible systems of inner crucible-silica crucible after cooling are fitted into crystal growing furnace；

Step 11: crucible is initially located at the high-temperature region of the upper furnace of crystal growing furnace, improves the furnace temperature of crystal growing furnace, Keep the furnace temperature of high-temperature region 30 DEG C~50 DEG C higher than polycrystalline fusing point, is 945 DEG C~965 DEG C；After polycrystal raw material is sufficiently melted and is overheated, Crucible is declined with the rate of 0.1mm/h~5mm/h, make crucible by the gradient zones 5 DEG C/cm~20 DEG C of temperature gradient/cm into Row crystal growth, after melt all passes through the solid-liquid interface of the temperature gradient zone of burner hearth, crystal growth terminates；Subsequent crystal Growth furnace cools to 600 DEG C with the speed of 2 DEG C/h, after then dropping to 250 DEG C with the speed of 5~15 DEG C/h furnace cooling to get To LiXSe₂Monocrystal, X=In/Ga/In_yGa_1-y。

The crucible pre-processes: the silica crucible of inner crucible and outer layer first being used acetone soak organic miscellaneous to remove Matter is impregnated to remove inorganic impurity with chloroazotic acid, is then cleaned up with deionized water, is dried.

The inner crucible is graphite crucible, PBN crucible or glass carbon crucible.

Beneficial effect

A kind of LiXSe proposed by the present invention₂(X=In/Ga/In_yGa_1-y) polycrystalline compounds and monocrystal preparation method, For solving the LiXSe of existing method preparation₂(X=In/Ga/In_yGa_1-y) monocrystal nonstoichiometry ratio the technical issues of. The technical solution cleans inner crucible and silica crucible first, and several simple substance of Li, In, Ga, Se are packed into inner crucible and quartz In crucible and Vacuum Package.The good silica crucible of sealing-in is fitted into rocking furnace, after being warming up to 180 DEG C, is slowly warming up to 260 DEG C, and after keeping the temperature 5h, 470 DEG C are then raised temperature to, 5h is kept the temperature again, is then warming up to LiXSe₂(X=In/Ga/In_yGa_1-y) change Object fusing point or more is closed, keeps the temperature, wave, be subsequently cooled to room temperature.Obtained LiXSe₂(X=In/Ga/In_yGa_1-y) compound meets Its stoichiometric ratio.Make tetra- kinds of simple substance of Li, In, Ga and Se in Li, Se under the lower vapour pressure of Li, Se by controlling temperature Nearby combination reaction occurs for fusing point, obtains Li₂Se、In_xSe_yAnd Ga_xSe_yEqual compounds, to fix the chemical activity of Li and Se, from And the loss of Li Yu Se ingredient are reduced, the LiXSe obtained using this method₂(X=In/Ga/In_yGa_1-y) polycrystal raw material grows The LiXSe arrived₂(X=In/Ga/In_yGa_1-y) monocrystal chemical component to the deviation of stoichiometric ratio can control 5% with It is interior.

The present invention prepares LiXSe using Li, In, Ga and Se simple substance₂(X=In/Ga/In_yGa_1-y) polycrystal raw material, change former There is technical solution to be brought rapidly up the technique for reacting raw material to 500 DEG C or more, stops raw material for a long time at low temperature, change Reaction is closed, to reduce the loss of Se and Li under high temperature, to more be met the LiXSe of stoichiometric ratio₂(X=In/Ga/ In_yGa_1-y) crystal, the program can be by the bias control of three kinds of ingredients within 5%.Three are controlled in synthesised polycrystalline raw material Element relative components are planted, and keep the method for its stoichiometric ratio in crystal growing process.Solve existing method growth LiXSe₂(X=In/Ga/In_yGa_1-y) compound monocrystal body, the problem of product component nonstoichiometry ratio

Detailed description of the invention:

Fig. 1: LiInSe₂The reaction temperature of component (Li-Se, In-Se, Li-In) two-by-two in system

Fig. 2: finished product detection report

Specific embodiment

Now in conjunction with embodiment, attached drawing, the invention will be further described:

The invention solves the LiXSe of existing method growth₂(X=In/Ga/In_yGa_1-y) compound monocrystal body, product at It provides one kind and controls three kinds of element relative components in synthesised polycrystalline raw material the problem of dividing nonstoichiometry ratio, and in crystalline substance The method of its stoichiometric ratio is kept in body growth course.

Steps are as follows by the present invention:

1. crucible process: successively using acetone, chloroazotic acid to impregnate to remove the silica crucible of the inner crucible of charge, outer layer Organic and inorganic impurity, is then cleaned up with deionized water, and drying is stand-by, and inner crucible is graphite crucible or PBN crucible Or glass carbon crucible；

2. passing through the pyrolysis organic matters such as acetone or methane under vacuum conditions using chemical vapour deposition technique, after the drying Inner wall of quartz crucible on deposit one layer of carbon film；

3. by Li, In (Ga) and tetra- kinds of element simple substances of tri- kinds of element simple substances of Se or Li, In, Ga, Se according to stoichiometry It is put into inner crucible than weighing, while on the basis of stoichiometric ratio 1:1:2, increasing the Li's and 1%-3% of 1%-3% Se；

4. covering plug to inner crucible, this plug can have following three kinds of ways of realization, and plug can be such that raw material seals It closes in a relatively closed space, reduces the loss of Li and Se；

5. covering the inner crucible of lid, it is put into the silica crucible for having plated carbon film, is evacuated down to 10^-4-10^-6Pa is used Oxyhydrogen flame seals silica crucible, and is put into and waves in conjunction material furnace；

6. being warming up to the fusing point (180 DEG C) of Li with the rate of 30-50 DEG C/h, Se is then warming up to the rate of 5-10 DEG C/h Fusing point more than (220 DEG C -260 DEG C, this temperature covers the reaction temperature of Li Yu Se and In and Se), then the temperature protect Warm 2-5h then with the rate of 5-30 DEG C/h is warming up to the reaction temperature (450 DEG C -500 DEG C) of Li and In and in the temperature 2-15h.In this step from 180 DEG C to Se fusing point more than and keep the temperature process, can make raw material all melt, Li, In, Ga and Se It can come into full contact with, and in Li-In, the reaction temperature of Li-Se, In-Se are kept the temperature respectively, so as to sufficiently react. It under conditions of holding low temperature, lower vapour pressure, reacts Se sufficiently with Li simple substance, forms Li₂Se、In_xSe_yAnd Ga_xSe_yDeng Compound, the enough effectively fixed Li and Se simple substance of the bond energys such as Li-Se, In-Se and Ga-Se of formation, reduces the chemical activity of Li, The evaporation capacity for reducing Se, to control the loss of Se and Li.

7. subsequent system is warming up to LiXSe with the rate of 50 DEG C/h₂(X=In/Ga/In_yGa_1-y) compound fusing point on (915 DEG C -930 DEG C) keep the temperature 12-36h.During incubation, rocking furnace can be opened, comes into full contact with the raw material of melting, chemical combination It is more uniform；

8. after heat preservation, furnace cooling after cooling to 700 DEG C with the rate of 10 DEG C/h.

9. by got in step 8 LiXSe₂(X=In/Ga/In_yGa_1-y) polycrystal raw material takes out from crucible, reload It is cleaned in advance and plated in the silica crucible of carbon film using chemical vapour deposition technique, and it is evacuated down to 10^-4-10^-6Pa is used Oxyhydrogen flame seals silica crucible；

10. inner crucible-silica crucible after cooling down in the silica crucible being sealed in step 9 or step 8 is double Crucible system is fitted into crystal growing furnace；

11. initial crucible is entirely located in the high-temperature region of the upper furnace of crystal growing furnace, the furnace temperature of crystal growing furnace is improved, The furnace temperature of high-temperature region is set to be higher than 30 DEG C -50 DEG C of polycrystalline fusing point (945 DEG C -965 DEG C).After polycrystal raw material is sufficiently melted and is overheated, earthenware Crucible is declined with the rate of 0.1mm/h-5mm/h, carries out crucible by the gradient zones of 5 DEG C/cm-20 DEG C/cm of temperature gradient brilliant Body growth, after melt all passes through the solid-liquid interface of the temperature gradient zone of burner hearth, crystal growth terminates.Subsequent crystal growth Furnace cools to 600 DEG C with the speed of 2 DEG C/h, furnace cooling after then dropping to 250 DEG C with the speed of 5-15 DEG C/h.It can be obtained LiXSe₂(X=In/Ga/In_yGa_1-y) monocrystal.