CN1189459A

CN1189459A - Nanometre titanium dioxide/silicon dioxide mesic hole compound and prepn. thereof

Info

Publication number: CN1189459A
Application number: CN98111113A
Authority: CN
Inventors: 冯素平; 孟国文; 张立德
Original assignee: INST OF SOLID PHYSICS CHINESE
Current assignee: Shandong Zhongke Nanometer Techn Co., Ltd.
Priority date: 1998-01-09
Filing date: 1998-01-09
Publication date: 1998-08-05
Anticipated expiration: 2018-01-09
Also published as: CN1058250C

Abstract

A nm-class TiO2/SiO2 mesoporous composition is prepared through preparing SiO2 mesoporous solid by sol-gel method, preparing butyl titanate solution with absolute alcohol as solvent, immersing the SiO2 mesoporous solid in butyl titanate solution for hydrolysis, baking and heat treatment, and features 500-740 sq.m/g of surfical area, the granularity of TiO2 particles less than 5 nm, and excellent optical characteristics (so it can be used for modulation of light suction in wider wavelength range).

Description

Nanometre titanium dioxide/silicon dioxide mesic hole compound and preparation method

The present invention relates to the preparation of nanometre titanium dioxide/silicon dioxide mesic hole compound.

Mesic hole compound is owing to the coupling at interface, and the influence of quantum confined effect and environment makes it have a series of special performances, therefore causes the great interest of people.About though the research of titanium dioxide and silicon dioxide composite material has report, but owing to the titanium dioxide environment difference of living in that is dispersed in the silicon dioxide base, titanium dioxide both can be in compound body opening, also can constitute the skeleton of complex body, this just grows up it easily unevenly when thermal treatment, and skewness, thereby the practical application of this titanium dioxide and silicon dioxide composite material is very restricted.Titanium dioxide is assembled into is considered to satisfactorily resolve the problems referred to above in the narrow mesoporous SiO 2 of pore size distribution, but the successful report of nanometre titanium dioxide/silicon dioxide mesic hole compound is not seen so far.

Purpose of the present invention just provides a kind of nanometre titanium dioxide/silicon dioxide mesic hole compound and preparation method, and the nano titanium oxide particle diameter is controlled.

The inventive method is a raw material with tetraethoxy, dehydrated alcohol and distilled water at first, prepares the mesoporous SiO 2 solid with sol-gel processing; Make solvent preparation butyl (tetra) titanate solution with dehydrated alcohol again; Then ready-made mesoporous SiO 2 solid is put into butyl (tetra) titanate solution and soak hydrolysis, oven dry is taken out in hydrolysis fully back, after titanium dioxide/silicon dioxide mesic hole compound is prepared in 400 ℃～700 ℃ thermal treatments.

Be described in detail the inventive method below:

Step 1. with tetraethoxy, dehydrated alcohol and distilled water is raw material, and acid as catalyst makes silicon dioxide gel, places it in gelation in 60 ℃～120 ℃ baking ovens, in slowly dry 2～3 weeks, obtains xerogel; Again xerogel is heat-treated 400 ℃～750 ℃ of temperature, make the mesoporous SiO 2 solid;

Step 2. with the dehydrated alcohol is solvent, the butyl (tetra) titanate solution of preparation 0.02～1M; The mesoporous SiO 2 solid that step 1 is made is put into the butyl (tetra) titanate solution for preparing and is soaked, and the butyl (tetra) titanate solution soaking is advanced in the mesoporous SiO 2;

Step 3. the mesoporous SiO 2 solid that step 2 is soaked is put into the aqueous solution, the rapid hydrolysis of the butyl (tetra) titanate in the mesoporous SiO 2, the product of hydrolysis is also stayed in the hole; After treating hydrolysis fully, take out drying, through 400 ℃～700 ℃ thermal treatments, make nanometre titanium dioxide/silicon dioxide mesic hole compound again.

The used acid of catalyzer can be hydrochloric acid, nitric acid in the inventive method step 1; Acid is 1: 2 with the mol ratio of silicon, and the mol ratio of tetraethoxy and water is 1: 10～15; Tetraethoxy and alcoholic acid mol ratio are 1: 3～5; Thermal treatment temp in the step 3 is 400 ℃～700 ℃, and the particle diameter of titanium dioxide can be controlled by the concentration of butyl (tetra) titanate in the step 2; Titanium dioxide footpath is subjected to also that thermal treatment temp influences in the step 3, raises with thermal treatment temp, and particle diameter has slightly grows up.

Mesoporous SiO 2 solid specific surface area with the inventive method preparation is 760m ²g ^-1, mean pore size is 5nm, the specific surface 5007～40m of mesic hole compound ²g ^-1, titanium dioxide nano-particle is evenly distributed in the complex body, and particle diameter is less than 5nm.

The inventive method characteristics are:

1. adopt the nanometre titanium dioxide/silicon dioxide mesic hole compound of mesoporous solid solution soaking hydrolysis method preparation, titanium dioxide nanoparticle is subjected to the restriction of mesoporous SiO 2, not obvious growing up;

2. the titanium dioxide in Zhi Bei the nanometre titanium dioxide/silicon dioxide mesic hole compound is evenly distributed, and particle diameter is less than 5nm;

3. Zhi Bei mesoporous SiO 2 solid specific surface area is 760m ²g ^-1, mean pore size is 5nm; Specific surface 500～the 740m of mesic hole compound ²g ^-1,

4. the concentration of used butyl (tetra) titanate in the preparation can be controlled the particle diameter of titanium dioxide;

5. heat treated temperature can be controlled the particle diameter of titanium dioxide.

In a word, the nanometre titanium dioxide/silicon dioxide mesic hole compound for preparing with the inventive method has outstanding optical characteristics, can realize the modulation of optical absorption edge in bigger wavelength region.

Embodiment:

In a beaker, add 50 milliliters of analytical pure tetraethoxys, add 50 milliliters of analytical pure dehydrated alcohols again, stir;

In another beaker, add 50 ml distilled waters, to wherein adding 5 milliliters of concentrated nitric acids, stir again;

Concentrated nitric acid in second beaker and distilled water solution are slowly splashed in first beaker, obtain clear sol and be placed on and make it that colloidal sol---gel conversion takes place in 80 ℃ of baking ovens, aging; Slowly dry 2～3 weeks transfer to baking oven 120 ℃ of oven dry 24 hours again, obtain silica xerogel, with 600 ℃ of thermal treatments of xerogel 2 hours, promptly obtain specific surface 760m ²g ^-1, mean pore size is the mesoporous SiO 2 solid of 5nm; Be solvent preparation 0.59M butyl (tetra) titanate solution with dehydrated alcohol in addition, the mesoporous SiO 2 solid that makes put in the butyl (tetra) titanate solution soaked 2 days, put into the distilled water immersion hydrolysis after the taking-up 1 day, take out oven dry, 600 ℃ of thermal treatments, promptly obtaining specific surface area is 600m then ²g ^-1, titanium dioxide nano-particle is evenly distributed, and particle diameter is less than the nanometre titanium dioxide/silicon dioxide mesic hole compound of 5nm.

Claims

1. the preparation method of a nanometre titanium dioxide/silicon dioxide mesic hole compound, it is characterized in that, with tetraethoxy dehydrated alcohol and distilled water is raw material, use colloidal sol---gel method is prepared the mesoporous SiO 2 solid, make solvent preparation butyl (tetra) titanate solution with absolute alcohol again, then ready-made mesoporous SiO 2 solid is put into butyl (tetra) titanate solution and soak hydrolysis, oven dry is taken out in hydrolysis fully back, through 400 ℃～700 ℃ thermal treatments, prepare the mesoporous complex of nanometre titanium dioxide/silicon dioxide again.

2. the method for claim 1 is characterized in that,

Step 1, with tetraethoxy, dehydrated alcohol and distilled water are raw material, acid as catalyst makes silicon dioxide gel, places it in gelation in 60 ℃～120 ℃ baking ovens, in slowly dry 2～3 weeks, obtains xerogel; Again xerogel is heat-treated 400 ℃～750 ℃, make the mesoporous SiO 2 solid;

Step 2. with the dehydrated alcohol is solvent, the butyl (tetra) titanate solution of preparation 0.02～1M; The butyl (tetra) titanate solution that the mesoporous SiO 2 solid that step 1 is made is put into preparation soaks, and the butyl (tetra) titanate solution soaking is advanced in the mesoporous SiO 2;

3. method as claimed in claim 2 is characterized in that, the used acid of catalyzer can be hydrochloric acid, nitric acid in the step 1; Acid is 1: 2 with the mol ratio of silicon, and the mol ratio of tetraethoxy and water is 1: 10～15; Tetraethoxy and alcoholic acid mol ratio are 1: 3～5; Thermal treatment temp in the step 3 is 400 ℃～700 ℃; The particle diameter of titanium dioxide can be controlled by the concentration of butyl (tetra) titanate in the step 2; Titanium dioxide footpath is subjected to also that thermal treatment temp influences in the step 3, raises with thermal treatment temp, and particle diameter has slightly grows up.

4. the nanometre titanium dioxide/silicon dioxide mesic hole compound of the method for claim 1 preparation is characterized in that mesoporous SiO 2 solid specific surface area is 760m ²g ^-1, mean pore size is 5nm; The specific surface of nanometre titanium dioxide/silicon dioxide mesic hole compound is 500～740m ²g ^-1, titanium dioxide nano-particle is evenly distributed in the complex body, and particle diameter is less than 5nm.