CN103641170B

CN103641170B - A kind of method of direct synthesizing submicron vanadic acid zirconium

Info

Publication number: CN103641170B
Application number: CN201310652076.8A
Authority: CN
Inventors: 刘芹芹; 程晓农; 姚金亮; 赵冰; 王利; 杨娟; 孙秀娟
Original assignee: Jiangsu University
Current assignee: Jiangsu University
Priority date: 2013-12-09
Filing date: 2013-12-09
Publication date: 2015-08-05
Anticipated expiration: 2033-12-09
Also published as: CN103641170A

Abstract

The present invention relates to negative thermal expansion material, be specifically related to the method for a kind of combustion method of citric acid direct synthesizing submicron vanadic acid zirconium.With ZrO (NO ₃) ₂5H ₂o and NH ₄vO ₃for raw material is mixed with the solution of volumetric molar concentration 0.5 ~ 1mol/L, respectively according to Zr ⁴⁺and V ⁵⁺mol ratio is that the ratio of 1:2 mixes two kinds of solution, and mixing solutions, after magnetic stirrer stirs 1 ~ 3 hour, adds citric acid complexing agent, ionizable metal salt (Zr ⁴⁺and V ⁵⁺) be 1:(2 ~ 7 with the mol ratio of citric acid); Add commercially available ammoniacal liquor adjust ph 7 ~ 12, then continue stirring 2 ~ 4 hours; Solution is put heating evaporation in a water bath, control temperature 60 ~ 80 DEG C, continuously stirring forms colloidal sol in 5 ~ 8 hours, is then heated further by this colloidal sol and forms gel in 2 ~ 4 hours; This gel obtains final product ZrV after 200 ~ 300 DEG C of burnings ₂o ₇.

Description

A kind of method of direct synthesizing submicron vanadic acid zirconium

Technical field

The present invention relates to negative thermal expansion material, be specifically related to the direct synthesizing submicron ZrV of a kind of combustion method of citric acid ₂o ₇method, adopt combustion method directly can obtain the negative thermal expansion material ZrV of well-crystallized ₂o ₇submicron powder, avoids the high temperature anneal in usual synthesis technique.

Background technology

The material with special negative expansion (Negative thermal expansion, NTE) functional performance has very high research and actual application value, and this kind of material is along with the rising volumetric shrinkage of temperature; This kind of material can with other positive thermal expansion material compounds, prepare and there is zero thermal expansion characteristic or the adjustable matrix material of thermal expansivity, to meet the application of the material in different field, surface as high-accuracy optical lens adopts Zero-expansion material to do coating, can prevent the optical property caused because of temperature variation from reducing; Using negative thermal expansion material as the packaged material of Bragg grating, temperature compensation can be carried out to grating, effectively improve the temperature stability of grating, promote optical-fibre communications industrial expansion; In structured material, apply low or zero thermal expansion stupalith, greatly can improve the thermal shock resistance of material, as various industrial furnace linings etc.; In addition negative expansion material also has potential using value in sensor.

At present, the negative thermal expansion material generally studied comprises ZrW ₂o ₈, Sc ₂w ₃o ₁₂and ZrV ₂o ₇three large series; In existing report, about ZrV ₂o ₇preparation all need to carry out solid state sintering at high temperature, although these class methods can prepare pure ZrV ₂o ₇but, there is preparation process complexity, length consuming time, the high deficiency of energy consumption; In recent years, without katolysis or calcination process, the nano-ceramic powder utilizing burning process to prepare soilless sticking oxide compound composition causes to be paid close attention to widely, the feature of this method is swift in response, chemical reaction institute heat requirement is provided by self, do not need external heat source, at present, directly obtain the negative thermal expansion material ZrV of well-crystallized with combustion method of citric acid ₂o ₇submicron powder has no report.

Summary of the invention

The present invention is the process characteristic according to combustion method, by Optimizing Process Parameters, directly utilizes combustion method of citric acid to obtain negative thermal expansion material ZrV ₂o ₇powder.

A kind of submicron ZrV ₂o ₇fast synthesis method, adopt combustion method of citric acid synthesizing submicron ZrV ₂o ₇, raw materials used is ZrO (NO ₃) ₂5H ₂o(analytical pure), NH ₄vO ₃(analytical pure), C ₆h ₈o ₇h ₂o(analytical pure), ammoniacal liquor (analytical pure); Burning synthesis method provided by the invention, technological process is simple, and preparation parameter is easy to control, reproducible, can mass-producing synthesis.

Preparation technology is:

(1) with ZrO (NO ₃) ₂5H ₂o and NH ₄vO ₃for raw material is mixed with solution respectively, according to Zr ⁴⁺and V ⁵⁺mol ratio is that the ratio of 1:2 mixes two kinds of solution, after mixing solutions stirs, adds the citric acid as complexing agent, ionizable metal salt (Zr ⁴⁺and V ⁵⁺) amount of substance sum and the mol ratio of citric acid be 1:(2 ~ 7); Add ammoniacal liquor adjust ph 7 ~ 12, then continue to stir;

(2) solution is put heating evaporation in a water bath, control temperature 60 ~ 80 DEG C, continuously stirring forms colloidal sol in 5 ~ 8 hours, then this colloidal sol is added thermosetting gel further at 80 ~ 120 DEG C;

(3) this gel obtains final product submicron ZrV after 200 ~ 300 DEG C of burnings ₂o ₇.

The concentration of the solution in step 1 controls at 0.5 ~ 1mol/L, is beneficial to follow-up coring and increment.

Ionizable metal salt (Zr in step 1 ⁴⁺and V ⁵⁺) amount of substance sum and the mol ratio of citric acid be 1:(3 ~ 5), adjust ph is 8 ~ 10 for good.

In step 2, bath temperature is 70 ~ 80 DEG C is good.

Accompanying drawing explanation

Fig. 1 the present invention prepares gained ZrV ₂o ₇xRD figure, as can be seen from the figure gained powder is pure ZrV ₂o ₇, free from foreign meter.

Fig. 2 the present invention prepares gained ZrV ₂o ₇sEM figure, as can be seen from the figure gained ZrV ₂o ₇particle size is at 100-200nm.

embodiment:

embodiment 1

Weigh 2.403g ZrO (NO ₃) ₂5H ₂o and 1.75g NH ₄vO ₃for the ZrO (NO that volumetric molar concentration is 0.5mol/L prepared respectively by raw material ₃) ₂5H ₂o and volumetric molar concentration are 0.5mol/L NH ₄vO ₃solution, according to Zr ⁴⁺and V ⁵⁺mol ratio is that the ratio of 1:2 mixes two kinds of solution, after mixing solutions fully mixes, add 9.431g citric acid complexing agent, and adopt commercially available ammoniacal liquor adjust ph to be 7, after stirring, solution is put heating evaporation in a water bath, control temperature 80 DEG C, continuously stirring forms colloidal sol in 5 hours, then this colloidal sol is heated 4h further in 80 DEG C, forms gel, gel, after 200 DEG C of combustion synthesis in airs, obtains final product ZrV ₂o ₇powder.

embodiment 2

Weigh 2.403g ZrO (NO ₃) ₂5H ₂o and 1.75g NH ₄vO ₃for the ZrO (NO that volumetric molar concentration is 1mol/L prepared respectively by raw material ₃) ₂5H ₂o and volumetric molar concentration are 1mol/L NH ₄vO ₃solution, according to Zr ⁴⁺and V ⁵⁺mol ratio is that the ratio of 1:2 mixes two kinds of solution, after mixing solutions fully mixes, add 18.862g citric acid complexing agent, and adopt commercially available ammoniacal liquor adjust ph to be 8, after stirring, solution is put heating evaporation in a water bath, control temperature 60 DEG C, continuously stirring forms colloidal sol in 7 hours, then this colloidal sol is heated 3h further in 100 DEG C, form gel.Gel, after 250 DEG C of combustion synthesis in airs, obtains final product ZrV ₂o ₇powder.

embodiment 3

Weigh 2.403gZrO (NO ₃) ₂5H ₂o and 1.75gNH ₄vO ₃for the ZrO (NO that volumetric molar concentration is 1mol/L prepared respectively by raw material ₃) ₂5H ₂o and volumetric molar concentration are 0.5mol/L NH ₄vO ₃solution, according to Zr ⁴⁺and V ⁵⁺mol ratio is that the ratio of 1:2 mixes two kinds of solution, mixing solutions is after fully mixing, add 28.293g citric acid complexing agent, and adopt commercially available ammoniacal liquor adjust ph to be 10, after stirring, solution is put heating evaporation in a water bath, control temperature 70 DEG C, continuously stirring forms colloidal sol in 6 hours, then this colloidal sol is heated 2h in 120 DEG C further, form gel.Gel, after 300 DEG C of combustion synthesis in airs, obtains final product ZrV ₂o ₇powder.

Claims

1. a method for direct synthesizing submicron vanadic acid zirconium, described ZrV ₂o ₇particle size, at 100-200nm, is characterized in that comprising the steps:

(1) with ZrO (NO ₃) ₂5H ₂o and NH ₄vO ₃for raw material is mixed with solution respectively, according to Zr ⁴⁺and V ⁵⁺mol ratio is that the ratio of 1:2 mixes two kinds of solution, after mixing solutions stirs, adds the citric acid as complexing agent, ionizable metal salt Zr ⁴⁺and V ⁵⁺amount of substance sum and the mol ratio of citric acid be 1:(2 ~ 7); Add ammoniacal liquor adjust ph 7 ~ 12, then continue to stir;

(2) solution is put heating evaporation in a water bath, control temperature 60 ~ 80 DEG C, continuously stirring forms colloidal sol, then this colloidal sol is added thermosetting gel further;

2. the method for a kind of direct synthesizing submicron vanadic acid zirconium as claimed in claim 1, is characterized in that: the concentration of the solution in step 1 controls at 0.5 ~ 1mol/L, is beneficial to follow-up coring and increment.

3. the method for a kind of direct synthesizing submicron vanadic acid zirconium as claimed in claim 1, is characterized in that: ionizable metal salt (Zr in step 1 ⁴⁺and V ⁵⁺) amount of substance sum and the mol ratio of citric acid be 1:(3 ~ 5), adjust ph is 8 ~ 10.

4. the method for a kind of direct synthesizing submicron vanadic acid zirconium as claimed in claim 1, is characterized in that: in step 2, bath temperature is 70 ~ 80 DEG C; The time of continuously stirring is 5 ~ 8 hours, and described further heating refers to heat 2-4h further at 80 ~ 120 DEG C.