CN1514448A

CN1514448A - Method of using acetate to prepare heat sensitire resistance oxide nano-powder

Info

Publication number: CN1514448A
Application number: CNA031542611A
Authority: CN
Inventors: 峰叶; 叶峰; 妥万禄
Original assignee: Xinjiang Technical Institute of Physics and Chemistry of CAS
Current assignee: Xinjiang Technical Institute of Physics and Chemistry of CAS
Priority date: 2003-08-16
Filing date: 2003-08-16
Publication date: 2004-07-21
Anticipated expiration: 2023-08-16
Also published as: CN1296945C

Abstract

In the method, acetate of Co, Mn, Ni is as raw material, and oxalic acid is as precipitator. Oxide nano powder of thermistor mixing acetate of Co, Mn, Ni is prepared after through treating procedures of mixing, coprecipitation, washing, decentralized processing, oven drying and burning. Granular size of powder is within 50-150 nm ranges generally. High performance NTC thermistor can be made from powder prepared according to the invented method, possessing advantages of high consistency in resistance value and B value, good interchangeability.

Description

The method for preparing the thermistor nm-class oxide powder with acetate

Technical field

The present invention relates to a kind of method for preparing NTC thermistor nm-class oxide powder with acetate.

Background technology

Coprecipitation is meant in containing the mixed solution of multiple metal cation salt and adds precipitation reagent, makes the method for all ion coprecipitations, can obtain composition and precipitate uniformly.It is the important method that preparation contains the composite oxides of two or more metallic elements.At present, coprecipitation is widely used in preparing the super-fine powder or the nano-powder material of functional ceramic such as sensitive material, ferrite, fluorescent material.The present invention compares through the analysis-by-synthesis to many preparation methods according to the liquid phase coprecipitation technology, has found out the method that a kind of suitable acetate prepares the thermistor nm-class oxide powder.

Summary of the invention

The object of the invention is to study a kind of method for preparing the thermistor nm-class oxide powder with acetate.It is raw material that this method adopts the acetate of Co, Mn, Ni, and oxalic acid is precipitation reagent, handles through operations such as stirring, co-precipitation, washing, dispersion treatment, oven dry, calcinings and prepares the thermistor nano-powder at last.The powder granule size generally in the 50-150nm scope, is reunited as occurring, and granular size does not generally wait at the 0.1-4 mu m range.Powder is the spinel structure phase.

The general traditional handicraft of oxide powder of preparation thermistor is a mechanical milling method, is not easy mixing with the powder component of this method preparation and reaches very even, and thermistor element resistance value consistency and the B value consistent performance manufactured are relatively poor.Have component and mix and adopt liquid-phase coprecipitation to prepare oxide powder, purity, controllable granularity, the powder granule degree is thinner, can realize that particle evenly mixes at atom, molecular level, preparation technology is fairly simple, equipment requirements is few, NTC thermistor with low cost, preparation can have high electrical resistance value consistency and B value consistency, exchange advantages such as better performances, therefore good practical value and application prospect are arranged.

Of the present inventionly prepare the method for thermistor nm-class oxide powder, press routine step and carry out with acetate:

A, take by weighing the acetate of Co, Mn, Ni as raw material at first respectively, its ratio is: Co: Mn: Ni=30-65: 20-40: 10-30, mix and dissolve in the deionized water, control metal ion acetate molar concentration is 0.05-0.4mol/L, is configured to the major constituent mixed solution;

B, usefulness oxalic acid are configured to precipitant solution as precipitation reagent, take by weighing with metal ion acetate mole ratio to be 1-2.0: the pure oxalic acid of 1 analysis dissolves in the deionized water, abundant stirring and dissolving, and the control molar concentration is 0.05-0.2mol/L;

C, Co, Mn, Ni acetate mixed solution slowly poured into carry out coprecipitation reaction in the oxalic acid precipitation agent solution, temperature is 10 ℃-80 ℃, constantly stirs in the time of reaction, with ammoniacal liquor pH value is controlled at 5-6;

D, the solution left standstill that reaction is finished fully deposit it, suction filtration or topple over the clear liquid of precipitation top, with the precipitation that deposits, wash with deionized water, clean dispersion treatment with absolute ethyl alcohol then, put into baking oven and carry out dried, to remove moisture in the powder at 60 ℃-100 ℃;

E, taking-up powder grind dispersion treatment, and powder is carried out calcination processing at 360-600 ℃, time 40-50 minute, promptly obtain Co-Mn-Ni ternary system thermistor nm-class oxide powder, the powder granule size is in the 50-150 nanometer, as occur reuniting, granular size is at 0.1-4 μ m.

Embodiment

Embodiment 1

A, at first by Co: Mn: Ni=30: take by weighing at 40: 30 and to analyze pure cobalt acetate, manganese acetate, nickel acetate chemical reagent, mix and dissolve in the deionized water, control metal ion acetate molar concentration is 0.05mol/L, is configured to the major constituent mixed solution;

B, with oxalic acid as precipitation reagent, be configured to precipitant solution, take by weighing with metal ion acetate mole ratio be that 1.2: 1 the pure oxalic acid of analysis dissolves in the deionized water, abundant stirring and dissolving, the control molar concentration is 0.05mol/L;

C, Co, Mn, Ni acetate mixed solution slowly poured into carry out coprecipitation reaction in the oxalic acid precipitation agent solution, temperature is 10 ℃, constantly stirs in the time of reaction, with ammoniacal liquor pH value is controlled at 5;

D, the solution left standstill that reaction is finished fully deposit it, and suction filtration or topple over the clear liquid of precipitation top, with the precipitation that deposits, wash with deionized water, clean dispersion treatment with absolute ethyl alcohol then, put into baking oven and carry out dried, to remove moisture in the powder at 60 ℃;

E, take out powder, grind dispersion treatment, powder is carried out calcination processing at 360 ℃, 40 minutes time, promptly obtain Co-Mn-Ni ternary system thermistor nm-class oxide powder, the powder granule size is in the 50-150 nanometer, no agglomerated particle

Embodiment 2

A, at first by Co: Mn: Ni=50: take by weighing at 40: 10 and to analyze pure cobalt acetate, manganese acetate, nickel acetate chemical reagent, mix and dissolve in the deionized water, control metal ion acetate molar concentration is 0.2mol/L, is configured to the major constituent mixed solution;

B, with oxalic acid as precipitation reagent, be configured to precipitant solution, take by weighing with metal ion acetate mole ratio be that 1.5: 1 the pure oxalic acid of analysis dissolves in the deionized water, abundant stirring and dissolving, the control molar concentration is 0.1mol/L;

C, Co, Mn, Ni acetate mixed solution slowly poured into carry out coprecipitation reaction in the oxalic acid precipitation agent solution, temperature is 50 ℃, constantly stirs in the time of reaction, with ammoniacal liquor pH value is controlled at 6;

D, the solution left standstill that reaction is finished fully deposit it, and suction filtration or topple over the clear liquid of precipitation top, with the precipitation that deposits, wash with deionized water, clean dispersion treatment with absolute ethyl alcohol then, put into baking oven and carry out dried, to remove moisture in the powder at 80 ℃;

E, taking-up powder grind dispersion treatment, and powder is carried out calcination processing 460,45 minutes time promptly obtained Co-Mn-Ni ternary system thermistor nm-class oxide powder, and the powder granule size is in the 60-120 nanometer, have soft-agglomeratedly, the agglomerated particle size is at 0.5-2 μ m.

Embodiment 3

A, at first by Co: Mn: Ni=65: take by weighing at 20: 15 and to analyze pure cobalt acetate, manganese acetate, nickel acetate chemical reagent, mix and dissolve in the deionized water, control metal ion acetate molar concentration is 0.4mol/L, is configured to the major constituent mixed solution;

B, with oxalic acid as precipitation reagent, be configured to precipitant solution, take by weighing with metal ion acetate mole ratio be that 2.0: 1 the pure oxalic acid of analysis dissolves in the deionized water, abundant stirring and dissolving, the control molar concentration is 0.2mol/L;

C, Co, Mn, Ni acetate mixed solution slowly poured into carry out coprecipitation reaction in the oxalic acid precipitation agent solution, temperature is 80 ℃, constantly stirs in the time of reaction, with ammoniacal liquor pH value is controlled at 6;

D, the solution left standstill that reaction is finished fully deposit it, and suction filtration or topple over the clear liquid of precipitation top, with the precipitation that deposits, wash with deionized water, clean dispersion treatment with absolute ethyl alcohol then, put into baking oven and carry out dried, to remove moisture in the powder at 100 ℃;

E, taking-up powder grind dispersion treatment, and powder is carried out calcination processing at 600 ℃, 50 minutes time promptly obtained Co-Mn-Ni ternary system thermistor nm-class oxide powder, and the powder granule size is in the 80-150 nanometer, occur soft-agglomeratedly, the agglomerated particle size is at 1-4 μ m.

Claims

1, a kind ofly prepare the method for thermistor nm-class oxide powder, it is characterized in that pressing routine step and carry out with acetate:

A, take by weighing the acetate of Co, Mn, Ni as raw material at first respectively, its ratio is: Co: Mn: Ni=30-65: 20-40: 10-30, mix and dissolve in the deionized water, control metal ion molar concentration is 0.05-0.4mol/L, is configured to the major constituent mixed solution;