Inorganic lead-cesium halide nanocrystalline composite chalcogenide glass ceramic material and preparation method thereof
Technical Field
The invention belongs to the field of functional glass ceramic materials, and particularly relates to an inorganic lead-cesium halide nanocrystalline composite chalcogenide glass ceramic material and a preparation method thereof, which can be applied to the fields of infrared optics and photonics.
Background
Inorganic perovskite CsPbX3The (X ═ Cl, Br, I) nanocrystals have the advantages of unique optical versatility, high luminescence quantum efficiency, and easy preparation, and have attracted extensive attention of researchers. However, CsPbX3The material is unstable in oxidative and humid atmospheric environments, which greatly limits the application of the material in various photoelectric fields, such as solar cells, lasers, displays and the like. Therefore, to increase CsPbX3The stability of nanocrystals is an effective method of complexing them with inert matrices such as organic polymers or inorganic glasses.
It is well known that optically functional nanocrystalline or quantum dot materials obtained by devitrification heat treatment in oxide glasses have excellent thermal and chemical stability. In recent years, various CsPbX have been reported3The nano crystal composite oxide glass ceramic and its novel photon characteristics and application, such as unique luminescence and random laser characteristics (J.Am.Ceram.Soc.,102[ 3)]1090-100(2019).;ACS Appl.Mater.Int.,10[22]18918-26(2018).;J.Mater.Chem.C,6[25]6832-39(2018).). However, the preparation strategy adopted in the work of the reported papers is to mix the relevant halide directly with the oxide raw material and to smelt under an open atmosphere. This preparation strategy inevitably leads to volatilization of the halide, resulting in poor reproducibility of sample preparation. Therefore, the glass composition and preparation method need to be redesigned, and various CsPbX types can be obtained repeatedly3A glass ceramic material compounded by nano crystals.
Unlike oxide glass, chalcogenide glass is obtained by melt-quenching in a vacuum-tight quartz glass tube. Chalcogenide glasses possess good halide solubility and do not suffer halide loss during the glass making process. In particular, chalcogenide glasses have unique low phonon energies, wide infrared transparent windows and good propertiesThe solubility of rare earth and other properties, and has good application prospect in various photon fields. In addition, although CsCl, RbI and Cs are present in chalcogenide glasses3LaCl6Isohalide nanocrystalline research reports, but CsPbX has never been obtained3Perovskite nanocrystalline composite chalcogenide glass ceramics. The CsPbX is prepared and obtained by careful composition design and crystallization treatment3The nanocrystalline composite chalcogenide glass ceramic has good research value and application significance.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: aiming at the defects of the prior art, the chalcogenide glass ceramic material is transparent in a spectral range of 2-10 microns, has good thermal and chemical stability and good fracture toughness, and is suitable for rare earth ion doping research and development of novel mid-infrared luminescent or laser materials and related quantum dot luminescent materials. The preparation method of the chalcogenide glass ceramic material can design and select proper glass composition according to functional requirements, and control precipitation of CsPbX3Grain size and distribution.
The technical scheme adopted by the invention for solving the technical problems is as follows: the molar composition of the inorganic lead-cesium halide nanocrystalline composite chalcogenide glass ceramic material is represented by the chemical formula: (1-x-y-z) GeS2·xSb2S3·yGa2S3·zCsPbX3Wherein X is 0.15-0.75, y is 0.05-0.2, z is 0.05-0.1, X is Cl, Br or I, CsPbX3Is compounded in the chalcogenide glass ceramic material in the form of precipitated nano crystals.
The molar composition of the inorganic lead-cesium halide nanocrystalline composite chalcogenide glass ceramic material is represented by the chemical formula: (1-x-y-z) GeS2·xSb2S3·yGa2S3·zCsPbX3Wherein X is 0.15-0.75, y is 0.05-0.2, z is 0.05-0.1, X is Cl, Br or I, the molar composition makes the content of the halide (namely cesium halide and lead halide) introduced into the base glass close to the supersaturation degree, and the later crystallization heat treatment process can be ensuredMiddle, CsPbX3The crystal can be separated out and CsPbX can be effectively controlled3The crystal grain size of the crystal is 5-50 nm, and the crystallinity is about 20%. Ga is appropriately introduced2S3Can improve the halogen coordination state in the glass network, improve the solubility of metal halide and ensure the doping amount of cesium halide and lead halide. From CsPbX3The chalcogenide glass ceramic material compounded by the nanocrystalline microcrystalline particles and the base glass is transparent in a spectral range of 2-10 micrometers, has good thermal and chemical stability and good fracture toughness, and is suitable for rare earth ion doping research and development of novel mid-infrared luminescent or laser materials and related quantum dot luminescent materials.
The preparation method of the inorganic lead-cesium halide nanocrystalline composite chalcogenide glass ceramic material comprises the following steps:
(1) selecting raw materials: according to the molar composition formula (1-x-y-z) GeS2·xSb2S3·yGa2S3·zCsPbX3Selecting Ge, Ga, Sb, S, CsX and PbX2Weighing simple substances Ge, Ga, Sb and S, CsX and PbX2The compound is prepared from raw materials, wherein X is 0.15-0.75, y is 0.05-0.2, z is 0.05-0.1, and X is Cl, Br or I;
(2) ge, Sb, S, CsX and PbX are mixed in dry atmosphere filled with inert gas2Mixing the raw materials, placing in a quartz ampoule, and vacuumizing to a vacuum degree of less than 10-3Pa, sealing the quartz ampoule by melting and placing the quartz ampoule in heating equipment;
(3) preparing base glass: heating equipment to 830-950 ℃, melting for 8-18 hours, cooling to obtain non-annealed glass, and measuring the glass transition temperature T of the non-annealed glass by a differential scanning calorimetry analyzergThen placing the unannealed glass in a precision annealing furnace for annealing, wherein the annealing temperature is higher than the glass transition temperature TgAnnealing at the constant temperature of 30 ℃ for 2-5 hours, and cooling to below 50 ℃ along with the furnace to obtain base glass;
(4) putting the base glass into a crystallization furnace with an inert atmosphere protection device for crystallization heat treatment, wherein the temperature of the crystallization heat treatment is higher than the glass transition temperature TgThe temperature is 10-40 ℃, and crystallization heat treatment is carried out for 3-100 hours at the temperature, so that a large amount of uniformly distributed CsPbX is precipitated in the glass3A nanocrystal; and finally, cooling to room temperature along with the furnace to obtain the inorganic lead-cesium halide nanocrystalline composite chalcogenide glass ceramic material.
Preferably, the specific preparation process of the base glass in the step (3) is as follows: heating the heating equipment to 340 ℃ slowly at a heating rate of less than 2 ℃/min, and keeping the temperature for 1-3 hours at the temperature; slowly heating the heating equipment to 750 ℃ at the heating rate of less than 5 ℃/min, and preserving the heat for 1-2 hours at the temperature; then slowly heating the heating equipment to 830-950 ℃ at the heating rate of 1-2 ℃/min, and preserving the temperature for 8-10 hours, wherein the quartz ampoule filled with the glass liquid is shaken or oscillated during the heat preservation; then, cooling to 780-900 ℃ at a cooling rate of 2-3 ℃/min; standing the quartz ampoule for 0.5-2 hours, and quenching in air or ice water mixture; in a precision annealing furnace at a specific glass transition temperature TgAnnealing at constant temperature of 30 ℃ for 2-5 hours, and then cooling to below 50 ℃ along with the furnace to obtain the base glass.
The invention relates to a method for preparing an inorganic lead-cesium halide nanocrystalline composite chalcogenide glass ceramic material, which uses GeS2-Sb2S3-Ga2S3For glass matrix, CsPbX is introduced to approach saturation3The components are prepared into basic chalcogenide glass by a melting quenching method, and then CsPbX can be controllably precipitated by crystallization heat treatment3Nanocrystalline to obtain the chalcogenide glass ceramic material. The method can design and select proper glass composition according to functional requirements, and control and precipitate CsPbX3Grain size and distribution. Compared with basic chalcogenide glass, the inorganic lead-cesium halide nanocrystalline composite chalcogenide glass ceramic material prepared by the method has the advantages of obviously improved thermodynamic stability and environmental impact resistance, and simultaneously has the rare earth ion doped luminescence enhancement performance and the quantum dot luminescence characteristic. Compared with the prior preparation method of the chalcogenide glass ceramic material, the controllable preparation method provided by the invention can be used for simply mixing and melting cesium halide, lead halide and chalcogenide glass matrix and recrystallizing the mixtureControl and precipitate CsPbX3And crystallizing to obtain the infrared transmitting chalcogenide glass ceramic with different properties.
Preferably, the CsPbX precipitated in the step (4)3The grain size of the nanocrystal is 5-50 nanometers.
Compared with the prior art, the invention has the advantages that: the molar composition of the inorganic lead-cesium halide nanocrystalline composite chalcogenide glass ceramic material is represented by the chemical formula: (1-x-y-z) GeS2·xSb2S3·yGa2S3·zCsPbX3Wherein X is 0.15-0.75, y is 0.05-0.2, z is 0.05-0.1, and X is Cl, Br or I, the molar composition enables the content of halide introduced into the base glass to be close to the supersaturation degree, and the CsPbX can be ensured in the later crystallization heat treatment process3The crystal can be separated out and CsPbX can be effectively controlled3The crystal grain size of the crystal is 5-50 nm, and the crystallinity is about 20%. From CsPbX3The chalcogenide glass ceramic material compounded by the nanocrystalline microcrystalline particles and the base glass is transparent in a spectral range of 2-10 micrometers, has good thermal and chemical stability and good fracture toughness, and is suitable for rare earth ion doping research and development of novel mid-infrared luminescent or laser materials and related quantum dot luminescent materials. The preparation method of the inorganic lead-cesium halide nanocrystalline composite chalcogenide glass ceramic material can design and select proper glass composition according to functional requirements, and control the precipitation of CsPbX3Grain size and distribution. Compared with basic chalcogenide glass, the inorganic lead-cesium halide nanocrystalline composite chalcogenide glass ceramic material prepared by the method has the advantages of obviously improved thermodynamic stability and environmental impact resistance, and has the characteristics of being suitable for rare earth ion doped luminescence enhancement and quantum dot luminescence. Compared with the prior preparation method of the chalcogenide glass ceramic material, the controllable preparation method provided by the invention can simply carry out the mixed melting and recrystallization treatment on cesium halide, lead halide and chalcogenide glass matrix to control the precipitation of CsPbX3And crystallizing to obtain the infrared transmitting chalcogenide glass ceramic with different properties.
Drawings
FIG. 1 is an X-ray diffraction pattern of a sulfur-based glass ceramic material of example 1;
FIG. 2 is a scanning electron micrograph of a chalcogenide glass ceramic material according to example 1;
FIG. 3 is an X-ray diffraction pattern of the sulfur-based glass ceramic material of example 3;
FIG. 4 is a scanning electron micrograph of a chalcogenide glass ceramic material from example 3.
Detailed Description
The invention is described in further detail below with reference to the examples of the drawings.
Example 1: taking X as Cl, X as 0.3, y as 0.1 and z as 0.06, the molar composition of the chalcogenide glass ceramic material is represented by the chemical formula: 54GeS2·30Sb2S3·10Ga2S3·6CsPbCl3Calculating the raw materials Ge, Ga, Sb, S, CsCl and PbCl according to the molar composition2Weighing in a glove box filled with inert gas and mixing uniformly; then putting the uniformly mixed raw materials into a quartz tube, soaking the quartz tube in king water for 2 hours in advance, washing the quartz tube with deionized water, drying the quartz tube, vacuumizing the quartz tube when the vacuum degree in the quartz tube is 10-3Sealing by melting with oxygen acetylene flame under Pa; putting the sealed quartz tube into a swinging furnace for heating, firstly heating to 340 ℃ at the speed of 2 ℃/min, preserving heat for 3 hours, then heating to 750 ℃ at the speed of 4 ℃/min, and preserving heat for 2 hours; slowly raising the temperature to 920 ℃ at the heating rate of 1 ℃/minute, and melting for 10 hours in a swinging manner; then the temperature is reduced to 850 ℃ at the speed of 3 ℃/min; standing a quartz ampoule, and quenching in an ice-water mixture after standing for 0.5 hour; finally, placing the glass in a precision annealing furnace at 240 ℃ for annealing, keeping the temperature for 5 hours, and then cooling the glass to below 50 ℃ along with the furnace to obtain base glass; and putting the obtained base glass into a crystallization furnace at the temperature of 270 ℃ for heat treatment for 20 hours, and finally cooling along with the furnace to obtain the inorganic lead-cesium halide nanocrystalline composite chalcogenide glass ceramic material.
The X-ray diffraction pattern of the sulfur-based glass ceramic material in example 1 is shown in FIG. 1, and the scanning electron micrograph is shown in FIG. 2. As can be seen from FIGS. 1 and 2, CsPbCl was precipitated from the sample after the crystallization heat treatment3Crystalline, with a grain size of about 20 nm. In addition, compare basic glassGlass, CsPbCl obtained3The glass transition temperature of the nanocrystalline composite chalcogenide glass ceramic is increased by 8 ℃, the fracture toughness is increased by 2 times, the hardness is enhanced by 10%, crack propagation is not observed under the action of micro-indentation, and the nanocrystalline composite chalcogenide glass ceramic has better thermal stability and environmental impact resistance.
Example 2: taking X as Cl, X as 0.5, y as 0.12 and z as 0.08, and the molar composition of the chalcogenide glass ceramic material is represented by the chemical formula: 30GeS2·50Sb2S3·12Ga2S3·8CsPbCl3Calculating the raw materials Ge, Ga, Sb, S, CsCl and PbCl according to the molar composition2Weighing in a glove box filled with inert gas and mixing uniformly; then putting the uniformly mixed raw materials into a quartz tube, soaking the quartz tube in king water for 2 hours in advance, washing the quartz tube with deionized water, drying the quartz tube, vacuumizing the quartz tube when the vacuum degree in the quartz tube is 10-3Sealing by melting with oxygen acetylene flame under Pa; putting the sealed quartz tube into a swinging furnace for heating, firstly heating to 340 ℃ at the speed of 2 ℃/min, preserving heat for 3 hours, then heating to 750 ℃ at the speed of 5 ℃/min, and preserving heat for 2 hours; then slowly raising the temperature to 850 ℃ at the heating rate of 1 ℃/minute, and melting for 10 hours in a swinging manner; then cooling to 800 ℃ at the speed of 2 ℃/min; standing a quartz ampoule, and quenching in an ice-water mixture after standing for 0.5 hour; finally, placing the glass in a precision annealing furnace at 220 ℃ for annealing, keeping the temperature for 3 hours, and then cooling the glass to below 50 ℃ along with the furnace to obtain base glass; and putting the obtained base glass into a crystallization furnace at the temperature of 240 ℃ for heat treatment for 20 hours, and finally cooling along with the furnace to obtain the inorganic lead-cesium halide nanocrystalline composite chalcogenide glass ceramic material. CsPbCl is precipitated from the sample after crystallization heat treatment3Crystalline, with a grain size of about 30 nm. In addition, CsPbCl was obtained as compared with the base glass3The glass transition temperature of the nanocrystalline composite chalcogenide glass ceramic is increased by 10 ℃, the hardness is enhanced by 15%, no crack propagation is observed under the action of micro-indentation, and the nanocrystalline composite chalcogenide glass ceramic has excellent thermal stability and environmental impact resistance.
Example 3: taking the molar composition of the chalcogenide glass ceramic material as chemical formula, wherein X is Br, X is 0.4, y is 0.2 and z is 0.07The formula is shown as: 33GeS2·40Sb2S3·20Ga2S3·7CsPbBr3Calculating the raw materials Ge, Ga, Sb, S, CsBr and PbBr according to the molar composition2Weighing in a glove box filled with inert gas and mixing uniformly; then putting the uniformly mixed raw materials into a quartz tube, soaking the quartz tube in king water for 2 hours in advance, washing the quartz tube with deionized water, drying the quartz tube, vacuumizing the quartz tube when the vacuum degree in the quartz tube is 10-3Sealing by melting with oxygen acetylene flame under Pa; putting the sealed quartz tube into a swinging furnace for heating, firstly heating to 340 ℃ at the speed of 2 ℃/min, preserving heat for 3 hours, then heating to 750 ℃ at the speed of 3 ℃/min, and preserving heat for 2 hours; slowly raising the temperature to 900 ℃ at the heating rate of 1 ℃/minute, and melting for 8 hours in a swinging manner; then cooling to 840 ℃ at the speed of 2 ℃/min; standing a quartz ampoule, and quenching in an ice-water mixture after standing for 0.5 hour; finally, placing the glass in a precision annealing furnace at 240 ℃ for annealing, keeping the temperature for 3 hours, and then cooling the glass to below 50 ℃ along with the furnace to obtain base glass; and (3) putting the obtained base glass into a crystallization furnace at the temperature of 270 ℃ for heat treatment for 10 hours, and finally cooling along with the furnace to obtain the inorganic lead-cesium halide nanocrystalline composite chalcogenide glass ceramic material.
The X-ray diffraction pattern of the chalcogenide glass-ceramic material in example 3 is shown in FIG. 3, and the scanning electron micrograph is shown in FIG. 4. As can be seen from FIGS. 3 and 4, CsPbBr was precipitated from the samples after the crystallization heat treatment3Crystalline, with a grain size of about 40 nm. In addition, CsPbBr obtained compared to the base glass3The glass transition temperature of the nanocrystalline composite chalcogenide glass ceramic is increased by 10 ℃, the fracture toughness is increased by 2 times, the hardness is enhanced by 8%, crack propagation is not observed under the action of micro-indentation, and the nanocrystalline composite chalcogenide glass ceramic has better thermal stability and environmental impact resistance.
Example 4: taking X as Br, X as 0.5, y as 0.1 and z as 0.1, the molar composition of the chalcogenide glass ceramic material is expressed by the chemical formula: 30GeS2·50Sb2S3·10Ga2S3·10CsPbBr3Calculating the raw materials Ge, Ga, Sb, S, CsBr and PbBr according to the molar composition2Is filled withWeighing in a glove box of sexual gas and mixing uniformly; then putting the uniformly mixed raw materials into a quartz tube, soaking the quartz tube in king water for 2 hours in advance, washing the quartz tube with deionized water, drying the quartz tube, vacuumizing the quartz tube when the vacuum degree in the quartz tube is 10-3Sealing by melting with oxygen acetylene flame under Pa; putting the sealed quartz tube into a swinging furnace for heating, firstly heating to 340 ℃ at the speed of 1 ℃/min, preserving heat for 3 hours, then heating to 750 ℃ at the speed of 4 ℃/min, and preserving heat for 2 hours; slowly raising the temperature to 880 ℃ at the heating rate of 1 ℃/minute, and melting for 8 hours in a swinging manner; then the temperature is reduced to 780 ℃ at the speed of 2 ℃/min; standing a quartz ampoule, and quenching in an ice-water mixture after standing for 0.5 hour; finally, placing the glass in a precision annealing furnace at 180 ℃ for annealing, keeping the temperature for 3 hours, and then cooling the glass to below 50 ℃ along with the furnace to obtain base glass; and putting the obtained base glass into a crystallization furnace at the temperature of 230 ℃ for heat treatment for 20 hours, and finally cooling along with the furnace to obtain the inorganic lead-cesium halide nanocrystalline composite chalcogenide glass ceramic material. CsPbBr is precipitated from the sample after crystallization heat treatment3Crystalline, with a grain size of about 50 nm. In addition, CsPbBr obtained compared to the base glass3The glass transition temperature of the nanocrystalline composite chalcogenide glass ceramic is increased by 12 ℃, the hardness is enhanced by 18%, no crack propagation is observed under the action of micro-indentation, and the nanocrystalline composite chalcogenide glass ceramic has better thermal stability and environmental impact resistance.
Example 5: taking X as I, X ═ 0.2, y as 0.05 and z as 0.05, the molar composition of the chalcogenide glass ceramic material is expressed by the chemical formula: 70GeS2·20Sb2S3·5Ga2S3·5CsPbI3Calculating the raw materials Ge, Ga, Sb, S, CsI and PbI according to the molar composition2Weighing in a glove box filled with inert gas and mixing uniformly; then putting the uniformly mixed raw materials into a quartz tube, soaking the quartz tube in king water for 2 hours in advance, washing the quartz tube with deionized water, drying the quartz tube, vacuumizing the quartz tube when the vacuum degree in the quartz tube is 10-3Sealing by melting with oxygen acetylene flame under Pa; heating the sealed quartz tube in a rocking furnace at 2 deg.C/min to 340 deg.C for 3 hr, and heating to 750 deg.C at 2 deg.C/minKeeping the temperature for 2 hours; slowly raising the temperature to 950 ℃ at the heating rate of 1 ℃/minute, and melting for 10 hours in a swinging manner; then the temperature is reduced to 860 ℃ at the speed of 2 ℃/min; standing a quartz ampoule, and quenching in an ice-water mixture after standing for 0.5 hour; finally, placing the glass in a precise annealing furnace at 260 ℃ for annealing, keeping the temperature for 3 hours, and then cooling the glass to below 50 ℃ along with the furnace to obtain base glass; and (3) putting the obtained base glass into a crystallization furnace with the temperature of 290 ℃ for heat treatment for 5 hours, and finally cooling along with the furnace to obtain the inorganic lead-cesium halide nanocrystalline composite chalcogenide glass ceramic material. CsPbI is precipitated from the sample after crystallization heat treatment3Crystalline, with a grain size of about 5 nm. In addition, the CsPbI obtained compared to the base glass3The glass transition temperature of the nanocrystalline composite chalcogenide glass ceramic is increased by 5 ℃, the hardness is enhanced by 8%, the fracture toughness is increased by 1.5 times, no crack propagation is observed under the action of micro-indentation, and the nanocrystalline composite chalcogenide glass ceramic has better thermal stability and environmental impact resistance.
Example 6: taking X as I, X ═ 0.15, y as 0.15 and z as 0.1, the molar composition of the chalcogenide glass ceramic material is expressed by the chemical formula: 60GeS2·15Sb2S3·15Ga2S3·10CsPbI3Calculating the raw materials Ge, Ga, Sb, S, CsI and PbI according to the molar composition2Weighing in a glove box filled with inert gas and mixing uniformly; then putting the uniformly mixed raw materials into a quartz tube, soaking the quartz tube in king water for 2 hours in advance, washing the quartz tube with deionized water, drying the quartz tube, vacuumizing the quartz tube when the vacuum degree in the quartz tube is 10-3Sealing by melting with oxygen acetylene flame under Pa; putting the sealed quartz tube into a swinging furnace for heating, firstly heating to 340 ℃ at the speed of 2 ℃/min, preserving heat for 3 hours, then heating to 750 ℃ at the speed of 2 ℃/min, and preserving heat for 2 hours; slowly raising the temperature to 930 ℃ at the heating rate of 1 ℃/minute, and melting for 10 hours in a swinging manner; then the temperature is reduced to 850 ℃ at the speed of 2 ℃/min; standing a quartz ampoule, and quenching in an ice-water mixture after standing for 0.5 hour; finally, placing the glass in a precision annealing furnace at 250 ℃ for annealing, keeping the temperature for 3 hours, and then cooling the glass to below 50 ℃ along with the furnace to obtain base glass; putting the obtained base glass into a crystallization furnace with the temperature of 280 DEG CAnd carrying out heat treatment for 5 hours, and finally cooling along with a furnace to obtain the inorganic lead and cesium halide nanocrystalline composite chalcogenide glass ceramic material. CsPbI is precipitated from the sample after crystallization heat treatment3Crystalline, with a grain size of about 30 nm. In addition, the CsPbI obtained compared to the base glass3The glass transition temperature of the nanocrystalline composite chalcogenide glass ceramic is increased by 12 ℃, the hardness is enhanced by 15%, the fracture toughness is improved by 2 times, no crack propagation is observed under the action of micro-indentation, and the nanocrystalline composite chalcogenide glass ceramic has better thermal stability and environmental impact resistance.