CN104692349A

CN104692349A - Method for performing CO2-enriched hydrothermal synthesis to gadolinium phosphate nanorod

Info

Publication number: CN104692349A
Application number: CN201410810264.3A
Authority: CN
Inventors: 张为; 周丽; 李和平; 陈柱; 李肃宁
Original assignee: Institute of Geochemistry of CAS
Current assignee: Institute of Geochemistry of CAS
Priority date: 2014-12-24
Filing date: 2014-12-24
Publication date: 2015-06-10
Anticipated expiration: 2034-12-24
Also published as: CN104692349B

Abstract

The invention discloses a method for performing CO2-enriched hydrothermal synthesis to a gadolinium phosphate nanorod. The method is characterized by comprising the following steps: respectively preparing a Gd<3+> salt solution and a PO4<3+> solution at room temperature; adding the two solutions into the reaction kettle according to the volume ratio of 1:1, stirring while adding, continuously stirring for 30min to 1h; introducing CO2 gas or dry ice into the reaction kettle, controlling the pressure in the kettle to be 1-10Mpa, and sealing and heating the high-pressure reaction kettle, setting the reaction temperature to be 100-200DEG C and the lasting time to be 12h-2d, then naturally cooling the high-pressure reaction kettle to room temperature; filtering the reacted product, washing sequentially with deionized water and anhydrous ethanol and centrifuging for twice; and drying the dried and centrifuged product for more than 6h at 50-100DEG C, thus obtaining a final pure product.

Description

A kind of rich CO 2the method of Hydrothermal Synthesis Gadolinium phosphate nanometer rod

Technical field

The present invention relates to a kind of preparation method of rare earth phosphate nanometer material, belong to functional materials synthesis technical field.

Background technology

In the periodic table of elements, gadolinium (Gd) is positioned at IIIB race, and ordination number is 64, belongs to light rare earths, and the content of gadolinium in the earth's crust is 0.000636%.In addition, the element of ordination number 57 to 71, they are called as lanthanon together with gadolinium.Lanthanon and yttrium of the same clan (Y) and scandium (Sc) are referred to as rare earth element.Rare earth element has special electron structure (4f ^0-145d ^0-16s ²), their out-shell electron is substantially identical, internal layer 4f electronic level is very close again, and 4f is the shell of a underfilling, electronic orbit is complete empty, be partly full of and be entirely full of the ion of electronics has optics inertia, for stable state, because of the feature of its outer electronic structure, make it have special physicochemical property.

RE phosphate material, because having the advantages such as specific refraction that in good thermostability, water, solubleness is minimum and high, is widely used in the fields such as luminescent material, stupalith, catalyzer, alloy material and lubricant.Gadolinium phosphate (GdPO ₄), be often used as the good matrix of other rare earth ion of doping.The luminescent material being matrix with nanometer Gadolinium phosphate have good stability, thermal capacitance large, there is high efficiency feature under the exciting of vacuum-ultraviolet light, excite because material particle size is less than or launches optical wavelength simultaneously, therefore light field can be approximately even in particle range, can significantly improve cathode tube and plasma display sharpness.Meanwhile, Gadolinium phosphate fusing point is high, with some oxide compound compounds, as Al ₂o ₃, high temperature resistant, anti-oxidant, that electrical insulating property the is good composite ceramics processed can be prepared.In addition, Gadolinium phosphate is also widely used in alloy material, catalytic material.Therefore the Gadolinium phosphate studying controlled monazite structure has great importance.

Current synthesizing rare-earth phosphoric acid salt mainly contains the methods such as sol-gel method, hydrothermal method, the precipitator method, solid phase method, combustion method and microwave method, wherein commonplace with hydrothermal synthesis method.Existing large quantity research shows that pH controls one of most important factor of the brilliant looks of rare earth phosphate nanometer material crystalline form, but adopt the method for Syntheses in water RE phosphate at present, all just in initial aqueous solution, have adjusted pH, there is no buffer pH, lacked the control of gradual change physical and chemical condition to the brilliant looks of its crystalline form, to there is crystallization degree be not very high, size be not very evenly, problem that controllability is not strong.At occurring in nature, the geologic fluids that the Ree-phospeate Minerals of hydrothermal origin is formed has certain CO usually ₂dividing potential drop, CO in hydrothermal solution ₂can the pH of buffered soln.The present invention is by making full use of CO ₂the feature of dividing potential drop buffered soln pH, the Gadolinium phosphate nanometer rod that Hydrothermal Synthesis purity is high, size uniform, crystallization degree are good, controllability is strong.

Summary of the invention

The technical problem to be solved in the present invention is: provide a kind of feature making full use of CO2 dividing potential drop buffered soln pH, the method for the Gadolinium phosphate nanometer rod that Hydrothermal Synthesis purity is high, size uniform, crystallization degree are good, controllability is strong.

Technical scheme of the present invention is: a kind of rich CO ₂the method of Hydrothermal Synthesis Gadolinium phosphate nanometer rod, under room temperature, prepares Gd respectively ³⁺salt and PO ₄ ³⁺salts solution; Be that 1:1 adds in reactor by above-mentioned two kinds of solution according to volume ratio, add and stir, and Keep agitation 30 min to 1 h; Logical CO in reactor ₂gas or add dry ice, controlling still internal pressure is 1-10 Mpa, sealed high pressure reactor; Heating high-pressure reactor, setting temperature of reaction is 100-200 DEG C, time length 12 h-2 d, and then naturally cooling autoclave is to room temperature; Reacted product is filtered, and priority deionized water and dehydrated alcohol respectively wash, centrifugal twice; By washing, centrifugal after product at 50 DEG C ~ 100 DEG C drying 6 more than h; Final clean product can be obtained.

Described Gd ³⁺salt and PO ₄ ³⁺salt is respectively conventional soluble g d ³⁺salt and solubility PO ₄ ³⁺salt.

Beneficial effect of the present invention:

(1) the present invention makes full use of CO ₂the pH of dividing potential drop buffered soln, the Gadolinium phosphate nanometer rod purity of Hydrothermal Synthesis is high, size uniform, crystallization degree are good, controllability is strong.

(2) organism that tensio-active agent, dispersion agent, coating etc. not can be recycled is not added in preparation process of the present invention, environmental friendliness.

Accompanying drawing explanation

Fig. 1 is the XRD figure of the Gadolinium phosphate that embodiment 3 is synthesized;

Fig. 2 is the SEM figure of the Gadolinium phosphate that embodiment 3 is synthesized.

Embodiment

Embodiment 1

Take the Gadolinium trinitrate [Gd (NO of certain mass ₃) ₃ 6H ₂o] and Secondary ammonium phosphate [(NH ₄) ₂hPO ₄], being made into concentration with deionized water is respectively the aqueous solution of the Gadolinium trinitrate of 0.36mol/L and the aqueous solution of Secondary ammonium phosphate.Be that 1:1 adds in reactor by Gadolinium trinitrate solution and ammonium dibasic phosphate solution according to volume ratio, add and stir, the initial compactedness controlling reactor is 70%, and Keep agitation 30 min to 1 h.Be filled with 1 MPa carbon dioxide to autoclave, close autoclave.Heating high-pressure reactor, controlling temperature of reaction is 180 DEG C, and 2 days time length, then autoclave naturally cools to room temperature.After reactor pressure release, product is filtered, centrifugal, and successively alternately respectively to wash twice with deionized water and dehydrated alcohol respectively, most relief product dry 12 h under 70 DEG C of environment.

Embodiment 2

Take the Gadolinium trinitrate [Gd (NO of certain mass ₃) ₃ 6H ₂o] and Secondary ammonium phosphate [(NH4) ₂hPO ₄], being made into concentration with deionized water is respectively the aqueous solution of the Gadolinium trinitrate of 0.36mol/L and the aqueous solution of Secondary ammonium phosphate.Be that 1:1 adds in reactor by Gadolinium trinitrate solution and ammonium dibasic phosphate solution according to volume ratio, add and stir, the initial compactedness controlling reactor is 70%, and Keep agitation 30 min to 1 h.Be filled with 5 MPa carbon dioxides to autoclave, close autoclave.Heating high-pressure reactor, controlling temperature of reaction is 180 DEG C, and 2 days time length, then autoclave naturally cools to room temperature.After reactor pressure release, product is filtered, centrifugal, and successively alternately respectively to wash twice with deionized water and dehydrated alcohol respectively, most relief product dry 12 h under 70 DEG C of environment.

Embodiment 3

Take the Gadolinium trinitrate [Gd (NO of certain mass ₃) ₃ 6H ₂o] and Secondary ammonium phosphate [(NH ₄) ₂hPO ₄], being made into concentration with deionized water is respectively the aqueous solution of the Gadolinium trinitrate of 0.36mol/L and the aqueous solution of Secondary ammonium phosphate.By Gadolinium trinitrate solution and Secondary ammonium phosphate, (solution is that 1:1 adds in reactor according to volume ratio, adds and stirs, and the initial compactedness controlling reactor is 70%, and Keep agitation 30 min to 1 h.Add dry ice (solidified carbon dioxide) to autoclave, controlling reacting kettle inner pressure is 10 Mpa, closes autoclave.Heating high-pressure reactor, controlling temperature of reaction is 180 DEG C, and 2 days time length, then autoclave naturally cools to room temperature.After reactor pressure release, product is filtered, centrifugal, and successively alternately respectively to wash twice with deionized water and dehydrated alcohol respectively, most relief product dry 12 h under 70 DEG C of environment.The product of XRD phenogram display synthesis is pure Gadolinium phosphate.Gadolinium phosphate nanometer rod size uniform, the crystallization degree of SEM phenogram display synthesis are good.

Claims

1. a rich CO ₂the method of Hydrothermal Synthesis Gadolinium phosphate nanometer rod, is characterized in that: under room temperature, prepares Gd respectively ³⁺salt and PO ₄ ³⁺salts solution; Be that 1:1 adds in reactor by above-mentioned two kinds of solution according to volume ratio, add and stir, and Keep agitation 30 min to 1 h; Logical CO in reactor ₂gas or add dry ice, controlling still internal pressure is 1-10 Mpa, sealed high pressure reactor; Heating high-pressure reactor, setting temperature of reaction is 100-200 DEG C, time length 12 h-2 d, and then naturally cooling autoclave is to room temperature; Reacted product is filtered, and priority deionized water and dehydrated alcohol respectively wash, centrifugal twice; By washing, centrifugal after product at 50 DEG C ~ 100 DEG C drying 6 more than h, final clean product can be obtained.

2. the rich CO of one according to claim 1 ₂the method of Hydrothermal Synthesis Gadolinium phosphate nanometer rod, is characterized in that: described Gd ³⁺salt and PO ₄ ³⁺salt is respectively conventional soluble g d ³⁺salt and solubility PO ₄ ³⁺salt.