CN101993240B - Preparation method of Ce3+doped lutetium silicate (Lu2SiO5) polycrystalline flashing optical ceramic - Google Patents

Preparation method of Ce3+doped lutetium silicate (Lu2SiO5) polycrystalline flashing optical ceramic Download PDF

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CN101993240B
CN101993240B CN 201010536133 CN201010536133A CN101993240B CN 101993240 B CN101993240 B CN 101993240B CN 201010536133 CN201010536133 CN 201010536133 CN 201010536133 A CN201010536133 A CN 201010536133A CN 101993240 B CN101993240 B CN 101993240B
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lu2sio5
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CN101993240A (en
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施鹰
林挺
邓莲芸
任玉英
谢建军
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University of Shanghai for Science and Technology
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Abstract

The invention relates to a method for realizing rapid preparation of a Ce3+doped lutetium silicate (Lu2SiO5) polycrystalline flashing optical ceramic by adopting a spark plasma sintering technique, which belongs to the technical field of preparing rare earth doping polycrystalline flashing ceramics. The method is characterized by comprising the following steps of: obtaining a Ce:Lu2SiO5 precursor precipitate through a proper Sol-gel process by taking lutetium chloride (LuCl3) and ethyl orthosilicate (Si(C2H5O)4) as initiative raw materials; then performing calcination synthesis under an air atmosphere at the temperature of between 900 and 1,300 DEG C; and performing heat preservation for 1 to 10 hours at the temperature to finally obtain primary particle 80-100 nanometer single phase Ce:Lu2SiO5 luminescent powder. By adopting a spark plasma sintering technique densification method, the densification process is quickly finished at a lower sintering temperature (below 1,350 to 1,450 DEG C) to obtain the Ce:Lu2SiO5 polycrystalline ceramic, wherein the heat preservation time is 3 to 15 minutes; and the polycrystalline ceramic is annealed for 2 to 15 hours under the air atmosphere at 1,000 DEG C to obtain a semi-transparent optical ceramic of which the relative density is 99.50 percent. The ceramic has high luminescent properties.

Description

A kind of Ce 3+Doping silicic acid lutetium (Lu 2SiO 5) preparation method of polycrystalline flicker optical ceramics
Technical field
The present invention relates to a kind of discharge plasma sintering technique (Spark Plasma Sintering) and prepare fast polycrystalline Lu 2SiO 5The processing method of flicker optical ceramics belongs to rear-earth-doped polycrystalline optical ceramics technical field of material.
Background technology
Inorganic scintillation material is strong owing to the receptivity to energetic ray (X ray, gamma-rays etc.), detection efficiency is high and radioprotective hardness is high, has been successfully applied to modern nuclear medicine and has detected in the imaging system.Material system mainly comprises Bi 4Ge 3O 12(BGO), PbWO 4(PWO), CsI (Tl), NaI (Tl), BaF 2And Lu 2SiO 5Deng.C.L.Melcher in 1992 and J.S.Schweitzer two people find Lu first 2SiO 5Monocrystalline is a kind of scintillator material of superior performance.Its density is 7.4g/cm 3, light output can reach 26300ph/Mev, and its photoyield is 4 ~ 5 times of BGO monocrystalline, and 75% of thallium doping NaI (Tl), luminescence decay time are 40ns only, are much better than the 700ns of 230ns, CsI (Tl) of NaI (Tl) and the 300ns of BGO.Recent two decades comes, Lu 2SiO 5The preparation method of monocrystalline has obtained huge progress, has developed the effective preparation methods such as crystal pulling method, falling crucible method and laser heated pedestal method (LHPG method).But from Lu 2SiO 5Physics-chem characteristic, its crystalline structure belongs to oblique system, has in different directions larger anisotropy, high quality large size Lu 2SiO 5The single crystal preparation difficulty, cost of manufacture is still very high.In addition, the segregation coefficient of Ce in melt also limited it at large size Lu 2SiO 5The appearance of sample cracking and dephasign easily occurs in the even distribution in the monocrystalline.Adopt polycrystalline ceramics preparation technology to develop isotropic Lu 2SiO 5Optical ceramics is expected to more easily realize the Uniform Doped of Ce ion, on the basis that guarantees its luminescent properties, has reduced Lu 2SiO 5Preparation cycle and cost, be the effective ways that solve this difficult problem.The Lu of preparation 2SiO 5Optical ceramics has potential high-luminous-efficiency and High detect efficiency, is expected to replace gradually monocrystalline in some application facet.
At present in the world to Lu 2SiO 5The polycrystalline ceramics preparation has had certain research report, and Yimin Wang etc. is with nano level polycrystalline Lu 2SiO 5Powder is raw material, and having prepared in the visible light wave range transmitance by heat and other static pressuring processes is 11% translucent Lu 2SiO 5The flicker optical ceramics, ceramic relative density reaches 99.8%; Lempicki etc. has prepared polycrystalline Lu by heat pressing process at 1700 ℃ 2SiO 5Optical ceramics, its photoyield reaches Ce:Lu 2SiO 5The 50-60% of monocrystalline, but its preparation process ubiquity technology difficulty is large, the shortcomings such as sintering temperature height.
The inventive method is adopting sol-gel method to prepare nanometer Lu 2SiO 5On the basis of luminescent powder, by discharge plasma sintering (Spark Plasma Sintering) technology, under lower sintering temperature, realize Ce:Lu 2SiO 5The quick preparation of flicker optical ceramics.
Summary of the invention
The purpose of this invention is to provide a kind of Ce 3+Doping silicic acid lutetium (Lu 2SiO 5) preparation method of polycrystalline flicker optical ceramics.By the synthetic at low temperatures preparation nano level of Sol-gel method Ce:Lu 2SiO 5Powder and in conjunction with discharge plasma sintering (Spark Plasma Sintering) technology has been realized Ce:Lu 2SiO 5The quick preparation of polycrystalline flicker optical ceramics.
A kind of Ce of the present invention 3+Doping lutetium silicate polycrystal flicker optical ceramics is characterized in that having following chemical molecular formula:
(Lu 1-xCe x) 2SiO 5,
Wherein: x is the molar content of rare earth doped Ce ion, x=0.001 ~ 0.05.
A kind of Ce of the present invention 3+The preparation method of doping lutetium silicate polycrystal flicker optical ceramics is characterized in that having following preparation process and step:
A. the precursor system is standby: the present invention is with lutecium chloride (LuCl 3) powder and tetraethoxy (Si (C 2H 5O) 4) in molar ratio 2:1 be dissolved in an amount of Virahol ((CH 3O) 2CHOH) in, simultaneously with cerous nitrate (Ce (NO 3) 3) and propylene oxide (C 3H 6O) introduce in the colloidal sol, guaranteed that through mix and blend rare earth atom Lu realizes evenly mixing with elements Si in the nanoscale scope; At room temperature reaction obtains Ce:Lu 2SiO 5Presoma;
B. above-mentioned presoma throw out is placed under the air atmosphere 50 ~ 120 ℃ of dryings after 5 ~ 40 hours, then under 900 ~ 1300 ℃ of temperature, calcine and realize Ce:Lu 2SiO 5Phase synthetic, soaking time 1 ~ 10 hour; Obtain single-phase Ce:Lu 2SiO 5Powder;
C. with above-mentioned synthetic single-phase Ce:Lu 2SiO 5It is the high-strength graphite mould of Φ 10 ~ 25mm that powder places internal diameter; Mould is put into the discharge plasma sintering stove carry out densification sintering, sintering temperature is in 1300 ℃ ~ 1450 ℃ scopes, and soaking time is 2 ~ 15min; Progressively pressurization reaches resulting pressure 30 ~ 80MPa at 800 ~ 1000 ℃ in the sintering process, and keeps pressure to insulation to finish; Sample cools to room temperature with the furnace;
D. to discharge plasma sintering gained sample 800 ~ 1300 ℃ of annealing, carry out subsequently two-sided fine grinding polishing, obtain translucent Ce:Lu 2SiO 5Polycrystalline flicker optical ceramics.
Ce:Lu of the present invention 2SiO 5The sintering method of polycrystalline flicker optical ceramics has the following advantages:
(1) guaranteed that rare earth atom Lu can evenly mix with elements Si, under lower synthesis temperature, obtains single-phase Ce:Lu in the nanoscale scope 2SiO 5Polycrystalline scintillating ceramic powder, the primary particle size size can be controlled in below the 100nm, and size distribution is even.
(2) by discharge plasma sintering (Spark Plasma Sintering) technology densifying method, moulding and the sintering of powder are once finished, under lower temperature (1300 ~ 1450 ℃), be prepared into relative density and reach as high as 99.50% Ce:Lu 2SiO 5The polycrystalline scintillating ceramic.Sintering time only needs several minutes, the polycrystalline Ce of acquisition: Lu 2SiO 5The pottery state that is translucent.The good luminous behavior of performance under ultraviolet excitation, main emission peak is positioned at the 420nm place.
Description of drawings
Fig. 1 is the TEM shape appearance figure of presoma powder among the present invention.
Fig. 2 is presoma of the present invention at 1100 ℃ of calcinings gained Ce:Lu after 2 hours 2SiO 5The TEM pattern of powder.
Fig. 3 is presoma of the present invention at 1100 ℃ of calcinings gained Ce:Lu after 2 hours 2SiO 5The electron diffraction picture of powder.
Fig. 4 is that presoma of the present invention is in 2 hours gained Lu of 1100 ℃ of calcinings 2SiO 5The SEM picture of powder, as seen from the figure, Ce:Lu 2SiO 5The single particle size distribution of powder is even, and the single particle size is about 100nm.
Fig. 5 is the synthetic Ce:Lu of the present invention 2SiO 5(0.5mol%) the excitation-emission spectrum of powder under UV-light, main excitation peak is positioned at 360nm, and emission peak is positioned at the 420nm place.
Fig. 6 is that presoma of the present invention obtains Ce:Lu through 1100 ℃ of calcinings after 2 hours 2SiO 5The XRD figure spectrum of powder and discharge plasma sintering optical ceramics shows that the preparation of sol-gel powder is single Ce:Lu 2SiO 5Phase forms and do not observe other dephasign existence, and phase composite remains unchanged in the ceramic post sintering process.
Fig. 7 is the optical ceramics that obtains after 5 minutes at 1350 ℃ of sintering.
Fig. 8 is the transparent Lu that 1000 ℃ of annealing obtain afterwards 2SiO 5Flicker optical ceramics (sample twin polishing, thickness is 1.0mm, and has shown its translucency).
Fig. 9 is Ce:Lu 2SiO 5Flicker optical ceramics and the emmission spectrum of monocrystalline under ultraviolet excitation, its emission peak all is positioned at the 420nm place.
Embodiment
Now details are as follows with specific embodiments of the invention.
Embodiment 1: preparation process and the step of this enforcement are as described below: with the lutecium chloride (LuCl of 40g 3) and the tetraethoxy (Si (C of 16.1ml 2H 5O ) 4) be dissolved in the Virahol ((CH of 285ml 3O) 2CHOH) in, other adds 1.36ml concentration is 0.522mol/L cerous nitrate (Ce (NO 3) 3), add subsequently 199.22mol propylene oxide (C 3H 6O), obtain white gels shape throw out after 30 hours through stirring reaction.Throw out was placed under 60 ℃ of conditions of air atmosphere dry 24 hours, then place alumina crucible, in retort furnace, synthesize calcining under 1100 ℃, be incubated 2 hours, obtain Ce:Lu 2SiO 5(0.5mol%) luminescent powder.
It is Φ 15mm high-strength graphite mould that powder is placed internal diameter, mould is put into the discharge plasma sintering stove carry out densification sintering, keep sintering environment vacuum tightness greater than 10Pa, temperature rise rate below 1000 ℃ is 80 ℃/min, and being controlled to be more than 1000 ℃ is 40 ℃/min, sintering temperature is 1400 ℃, soaking time is 6min, and progressively pressurization reaches resulting pressure 60MPa at 1000 ℃ in the sintering process, and keeping pressure to finish to insulation, sample cools to room temperature with the furnace.Sample is annealed in air atmosphere, and annealing conditions is 1000 ℃.After the fine grinding polishing, obtain translucent Lu 2SiO 5The flicker optical ceramics, its relative density can reach 99.5%.Show good luminescent properties under the burst of ultraviolel condition, its luminous intensity reaches Ce:Lu 2SiO 575% of monocrystalline.
Embodiment 2: preparation process and the step of the present embodiment are as described below: with the lutecium chloride (LuCl of 15g 3), the tetraethoxy of 6ml (Si (C 2H 5O) 4) be dissolved in the Virahol ((CH of 107ml 3O) 2CHOH) in, other adds 0.51ml concentration is 0.522mol/L cerous nitrate (Ce (NO 3) 3) solution, add subsequently 74.71ml propylene oxide (C 3H 6O), stirring reaction obtains white gels shape throw out after 30 hours.Throw out was placed under 60 ℃ of conditions of air atmosphere dry 24 hours, then place alumina crucible, in retort furnace, carry out calcination processing under 1100 ℃, be incubated 2 hours, obtain Ce:Lu 2SiO 5(0.5mol%) luminescent powder.
It is Φ 15mm high-strength graphite mould that powder is placed internal diameter, mould is put into the discharge plasma sintering stove carry out densification sintering, keep sintering environment vacuum tightness greater than 10Pa, temperature rise rate below 1000 ℃ is 160 ℃/min, is 80 ℃/min more than 1000 ℃, sintering temperature is 1350 ℃, soaking time is 5min, and progressively pressurization reaches resulting pressure 60MPa at 1000 ℃ in the sintering process, and keeping pressure to finish to insulation, sample cools to room temperature with the furnace.Sample is annealed in air atmosphere, and annealing conditions is 1000 ℃.After the fine grinding polishing, obtain translucent Lu 2SiO 5The flicker optical ceramics, its relative density can reach 99.1%.Show good luminescent properties under the burst of ultraviolel condition, its luminous intensity reaches Ce:Lu 2SiO 570% of monocrystalline.

Claims (1)

1. Ce 3+The preparation method of doping lutetium silicate polycrystal flicker optical ceramics is characterized in that having following preparation process and step:
A. the preparation of presoma powder: with lutecium chloride (LuCl 3) powder and tetraethoxy (Si (C 2H 5O) 4) in molar ratio 2:1 be dissolved in an amount of Virahol ((CH 3O) 2CHOH) in, simultaneously with cerous nitrate (Ce (NO 3) 3) and propylene oxide (C 3H 6O) introduce in the colloidal sol, at room temperature reaction obtains Ce:Lu 2SiO 5Presoma;
B. above-mentioned presoma throw out is placed under the air atmosphere 50 ~ 120 ℃ of dryings after 5 ~ 40 hours, then under 900 ~ 1300 ℃ of temperature, calcine and realize Ce:Lu 2SiO 5Synthesizing of phase, soaking time 1 ~ 10 hour obtains single-phase Ce:Lu 2SiO 5Powder;
C. with above-mentioned synthetic single-phase Ce:Lu 2SiO 5It is the high-strength graphite mould of Φ 10 ~ 25mm that powder places internal diameter; Mould is put into the discharge plasma sintering stove, and sintering temperature is 1300 ℃ ~ 1450 ℃, and soaking time is 2 ~ 15min; Progressively pressurization reaches resulting pressure 30 ~ 60MPa at 800 ~ 1000 ℃ in the sintering process, and keeps pressure to insulation to finish;
D. carry out two-sided fine grinding polishing after discharge plasma sintering gained sample being annealed through 800 ~ 1300 ℃ of conditions, obtain translucent Ce:Lu 2SiO 5Polycrystalline flicker optical ceramics.
CN 201010536133 2010-11-09 2010-11-09 Preparation method of Ce3+doped lutetium silicate (Lu2SiO5) polycrystalline flashing optical ceramic Expired - Fee Related CN101993240B (en)

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WO2014210040A1 (en) * 2013-06-24 2014-12-31 Schlumberger Canada Limited Method for forming lanthanide scintillators

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CN102557598B (en) * 2011-03-21 2014-10-01 上海大学 Pressureless sintering preparation method of Ce:Lu2SiO5 polycrystal flicker optical ceramics
CN102584188A (en) * 2011-12-16 2012-07-18 中国科学院上海硅酸盐研究所 Method for preparing an LSO (lutecium orthosilicate) asymmetrical system semitransparent ceramic by vacuum sintering process
CN103695001B (en) * 2013-12-06 2016-08-17 中国科学院高能物理研究所 A kind of nanoscale silicic acid lutecium flicker raw powder's production technology
CN103884664A (en) * 2014-03-24 2014-06-25 中国科学院上海硅酸盐研究所 Method for determining concentration of cerium ions in cerium-doped scintillation crystal
CN105330289B (en) * 2014-08-14 2018-08-31 清华大学 A kind of gadolinium oxysulfide（Gd2O2S）Scintillating ceramic preparation method
CN106542813A (en) * 2016-11-25 2017-03-29 湖北工业大学 The method for preparing nanoscale lutetium silicate polycrystal scintillating ceramic powder
CN107417276B (en) * 2017-07-14 2021-02-23 上海大学 Textured cerium-doped lutetium silicate scintillating ceramic and preparation method thereof
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CN112062472B (en) * 2020-08-31 2021-12-17 华南理工大学 High-hardness Lu2Si2O7Transparent microcrystalline glass and preparation method thereof

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