CN1844000A

CN1844000A - A permanent self-cleaning glass with visible light response and its preparation method

Info

Publication number: CN1844000A
Application number: CN 200610035099
Authority: CN
Inventors: 唐振方; 刘欣
Original assignee: Jinan University
Current assignee: JIEYANG HONGGUANG COATED GLASS CO Ltd
Priority date: 2006-04-21
Filing date: 2006-04-21
Publication date: 2006-10-11
Anticipated expiration: 2026-04-21
Also published as: CN100551858C

Abstract

The invention belongs to functional material technology and glass processing field, concretely discloses a permanent self-cleaning glass with visible light response and method for making it. Firstly, sputtering silica dioxide film on the surface of glass, sputtering a layer of titanium oxide film with anion and cation codoping on the surface of silica dioxide film, annealing the glass with twin layer films at 500-600 DEG C, cooling by radiation in sintering stove, to get the product. The self-cleaning glass has good photocatalysis property and photo-induced hydrophilicity, stable performance, almost perpetual availability, high light transmittance ratio and transparency. It is widly used in glass curtain wall of skyscrapers, automobile glass, road lamp shade, kitchen galss and antifog glass, avoiding artificial cleaning indoor and outdoor glass of skyscrapers, saving manual power and material, reducing corrosion destruction of cleaning agent to glass and building machinery, embodying environment protection notion.

Description

A kind of have visible light-responded permanent self-cleaning glass and preparation method thereof

Technical field

The invention belongs to functional materials technology and glass processing field, be specifically related to a kind of glass with new function material preparation and preparation method thereof with visible light-responded permanent self-cleaning performance.

Technical background

Self-cleaning glass be grow up recent years a kind of novel glass material, can be widely used on the glass and glasswork relevant with people's living environment.As building glass, cladding glass, partition glass, decoration glass, automobile windshield, automobile side window glass, speculum, skylight glass, light fixture lamp shade glass, cover-plate glass, hospital surgical equipment, kitchen glass, glass for lenses, household appliance glass, instrument glass, special operation glass etc.But, self-cleaning glass development at present also comes with some shortcomings, automatically cleaning effect as it is relatively poor, can only just have the automatically cleaning effect under given conditions, simultaneously, the automatically cleaning effect time is short, after the self-cleaning glass surface is exposed to and crosses for a long time in the contaminated air, loses efficacy owing to the surface is covered dirty being easy to by dust.

Studying a kind of glass that really has permanent automatically cleaning effect is a secular problem.Research method is a lot of at present, and mainly several is that glass is carried out finishing, and common has: have the film of self-cleaning function at glass surface plating one deck, or utilize the high-energy ion bombardment glass surface to improve surface energy etc.Thin-film material with self-cleaning function can be a silicon-dioxide, titanium dioxide or the like, and the characteristics of these materials are to have photocatalysis performance or photic wetting ability.Automatically cleaning principle with photocatalytic material is to utilize material breakdown to be adsorbed on the organism of material surface, organic polymer is degraded to small molecules, thereby reach self-cleaning purpose, shortcoming is that the decomposed substance on surface is not easy to remove, and uses the rear surface material that is decomposed easily to cover and lose self-cleaning function for a long time.And the automatically cleaning principle of hydrophilic material is because material surface has Superhydrophilic, can form moisture film on the surface.After pollution substance is adsorbed on material surface, just be easy to be washed away, reach self-cleaning purpose by water.But the material of this only possess hydrophilic property energy can not decompose the pollutent of surface adsorption, when the surface contamination material gathers the hydrophilic-structure of enough destruction material surfaces, will lose self-cleaning function.Since finding to have in 1972 after photolysis water and nineteen ninety-five find to have photic hydrophilic effect, nano titanium oxide has the extensive concern that has been subjected to material circle owing to have these two character simultaneously, is used in gradually above the development self-cleaning glass.But simple nano-titanium dioxide film can only be in exciting light catalytic under the UV-light and photic wetting ability, do not respond for the visible light part, range of application mainly concentrates on outdoor cladding glass and the indoor zone that UV-irradiation is arranged, as the hospital disinfection district etc., the just very faint even not reaction of automatically cleaning effect under the weather of common interior lighting and outdoor darkness.Simultaneously, the photocatalysis thin film on surface lost efficacy when being subjected to outside contamination and mechanical friction easily, and real effective service life is limited.The Activ that Britain Pilkington company produces ^TMSelf-cleaning antifog glass is the gold mark in self-cleaning glass field now, its surface TiO ₂Photic wetting ability of film and photocatalytic effect do not respond indoor, and outdoor response speed is slower, need 5 day time to activate fully.In actual use, even under the complete sunny weather condition in south, also need the sun 2-5 talent that is exposed to the sun to have antifog preferably and automatically cleaning effect.This has limited the application space of self-cleaning glass greatly.

Summary of the invention

The objective of the invention is to overcome the deficiency that existing self-cleaning glass exists, a kind of visible light-responded permanent self-cleaning glass that has is provided.

Another object of the present invention provides the preparation method of above-mentioned self-cleaning glass.

Self-cleaning glass of the present invention is by reaching the automatically cleaning purpose under the visible light at plating function film on the surface of ordinary glass.Described function film is a modified nano-titanium dioxide thin film, and its composition is Ti _1-xW _xO1 _-yN _y(x, y=0.5).Utilize tungsten and nitrogen to replace part titanium and oxygen respectively according to band theory in titanium dioxide, wherein tungsten ion is incorporated in the titanium dioxide by the mixing and ball milling targetry.And reach doping nitrogen ionic purpose by rf magnetron sputtering in nitrogen atmosphere.

Principle of the present invention is the nano titanium dioxide photocatalysis film that applies one deck modification in surface of ordinary glass.Nano titanium oxide itself has certain photocatalysis characteristic, but its photocatalysis characteristic can only excite under ultraviolet ray, for partly not response of visible light.The quantitative nitrogen that mixes therein replaces oxygen, forms the oxygen room, simultaneously impurity band can and titanium dioxide effectively overlap, make and pass through TiO in the life cycle of photoexcitation carrier ₂Be delivered to surface reaction, and low being with can responding to visible light.In doping nitrogen, Doped Tungsten ion also, tungsten ion has the effect of stored energy, and it is right to store visible light and ultraviolet ray excited electronics-hole, prolongs its recombination time, also can not lose efficacy thereby self-cleaning glass was stored for a long time in the dark.

Self-cleaning glass of the present invention also has one deck nanometer titanium dioxide silicon film between glass surface and function film.The effect of nanometer titanium dioxide silicon film is to serve as the blocking layer in the post annealed process, in case in the annealing process in the glass ingredient sodium ion, potassium ion and calcium ion etc. be penetrated in the nano-titanium dioxide film of modification and go, influence the performance of follow-up modified film, also can prevent simultaneously in use these ionic infiltrations in the glass.

The preparation method of self-cleaning glass of the present invention comprises the steps: 1) preparation sputter titanium dioxide hybrid target: the doping tungstic oxide prepares hybrid target in titanium dioxide, and the mol ratio of tungsten and titanium is 1: 19～49; Press proportioning mixing and ball milling, high temperature sintering in sintering oven then with titania powder and tungsten trioxide powder.2), cleaning glass: the common spot in water cleaning glass surface at first, utilize " washing lotion " to soak glass again and utilize deionized water ultrasonic cleaning repeatedly after 3 hours.The ultrasonic cleaning time is 5～15min, and wash number is 3～5 times.3), utilize magnetron sputtering at glass surface sputter silica membrane, the thickness of sputtered film is 20～30nm.4), in the presence of the nitrogen argon gas, utilize magnetron sputtering sputter titanium dioxide hybrid target on the surface of nanometer titanium dioxide silicon film, obtain modified nano-titanium dioxide thin film; Thickness is 30～80nm.5), the glass that plated bilayer film is at 500～600 ℃ of annealing after 3～5 hours down, naturally cooling in the sintering oven.

In above-mentioned preparation method, glass substrate is a simple glass, and the washing lotion composition is the vitriol oil and potassium bichromate.In the washing lotion of during immersion whole glass surface being submerged, soak time is 3 hours.Magnetron sputtering is the radio frequency reaction magnetron sputtering, and sputtering target material is the pure silicon dioxide target during preparation silica membrane.Sputtering atmosphere is a pure argon.Operating pressure is 0.8～1.2Pa during the sputter reaction, and sputtering power is 180W.Sputtering time 2～4h.Target is the hybrid target of doping tungstic oxide during preparation modifying titanium dioxide film, and sputtering atmosphere is nitrogen and argon gas, and its component volume ratio is pressed N ₂/ (N ₂+ Ar) be 0.5～1, operating pressure is 0.8～1.5Pa during the sputter reaction.Sputtering power is 180～250W, and sputtering time is 3～8h; The glass substrate temperature is 100～150 ℃.During annealing, the temperature rise rate of sintering oven remains on 1 ℃/min.

Compare with existing self-cleaning glass, the present invention has following beneficial effect:

1, has good hydrophilicity.At wavelength is 400nm-700nm, and power is under the white light irradiation of 8W behind the 60min, and the contact angle of water 72 ° when initial become 5 °, have Superhydrophilic.Simultaneously, when preserving in the dark, the wetting ability out-of-service time is longer, after the illumination contact be 5 °, preserve 4 days in the dark after, contact angle only is 21 °.

2, has high visible light response activity.Test the self-cleaning glass that this experimental technique prepares down at visible light (wavelength 400nm-700nm), the rate of decomposition of methylene blue can reach 0.06893hr ^-1

3, have good corrosion resistance and friction resistant performance.In concentration is to soak 24 hours in the NaOH solution of 1mol/L, transmission of visible light difference DELTA T＜1% before and after soaking, and superficial film does not have considerable change.Soaked 24 hours in the HCl of 1mol/L solution, transmission of visible light difference DELTA T is about 1% before and after soaking, and superficial film does not have considerable change.At 500g, under the 200r, transmission of visible light difference DELTA T is about 1.01% before and after the meter layer film mill.

4, the self-cleaning glass uniformity of film of the inventive method preparation is good, glass color difference value Δ E*ab=2.6～2.8CIELAB.The visible region average transmittance is more than 80%.

5, preparation method of the present invention prepares photocatalysis thin film by the radio frequency reaction magnetron sputtering, and plated film is even, and thickness is controlled easily, both has been suitable for prepared in laboratory research, also is suitable for the big area industrial production.The glass curtain wall that can be widely used in skyscraper, vehicle glass, the street lamp lampshade, kitchen glass, and antifog glass (the bathroom antifog glass is decorated antifog glass) or the like.The widespread use of glass of the present invention can be exempted the artificial cleaning of skyscraper indoor and outdoor glass, uses manpower and material resources sparingly, and reduces the artificial corrosion and the destruction to glass and building structure of using sanitising agent to bring of cleaning, and embodies the environmental protection notion.

Description of drawings

Fig. 1 is the structure of permanent self-cleaning glass of the present invention;

Fig. 2 is a permanent self-cleaning glass preparation method flow process of the present invention;

Fig. 3 is the variation diagram of permanent self-cleaning glass of the present invention contact angle before and after radiation of visible light.

Among Fig. 1,1 is the modifying titanium dioxide film, and 2 is the nanometer titanium dioxide silicon film, and 3 is the simple glass substrate.

Embodiment

Embodiment 1

Glass cutting is become the size of needs.Water cleaning glass surface blot; The glass of washing surperficial dirt off is immersed in the washing lotion 3 hours, again with deionized water ultrasonic cleaning 5 times repeatedly, each 10min.Cleaning the back dries up with nitrogen; Utilize rf magnetron sputtering at glass surface sputter one deck nanometer titanium dioxide silicon film.Sputtering target material is the pure silicon dioxide target, and sputtering atmosphere is a pure argon, and sputter pressure is 0.8Pa, and sputtering power is 180W, and the glass substrate temperature is 150 ℃, sputtering time 4 hours, and sputter nano silicon film thickness is for being about 30nm; With titania powder and tungsten trioxide powder (mol ratio of tungsten and titanium is 1: 19) mixing and ball milling, high temperature sintering in sintering oven then in proportion; At the radio frequency reaction magnetron sputtering titanium dioxide hybrid target of using on glass of surface plating nanometer titanium dioxide silicon film, sputtering atmosphere is N ₂/ (Ar+N ₂)=2/3, operating pressure is 1.0Pa, sputtering power is 250W, 150 ℃ of glass substrate temperature, sputtering time 6 hours, obtain modified nano-titanium dioxide thin film that thickness is about 60nm after, in sintering oven, anneal, annealing temperature is 500 ℃, and temperature rise rate is 1 ℃/min, soaking time naturally cooling in the sintering oven after 3 hours.The structure of gained glass such as Fig. 1, preparation flow such as Fig. 2.

Self-cleaning glass prepared by this method is 400nm-700nm in illumination wavelength, and power is 8W, and behind the 60min, contact angle is reduced to below 5 ℃ by 72 ℃, has super hydrophilic effects under the spacing 7cm radiation of visible light.Fig. 3 is seen in the variation of the self-cleaning glass that makes contact angle before and after radiation of visible light.

Claims

1. A kind of self-cleaning glass, which has a self-cleaning function under visible light by coating a functional film on the glass surface. It is characterized in that the functional film is a modified nano-titanium dioxide film, and its molecular formula is: Ti _1-x W _x O _1-y N _y , x, y = 0.5.

2. The self-cleaning glass according to claim 1, characterized in that there is a layer of nano silicon dioxide film between the glass surface and the functional film.

3. The method for preparing self-cleaning glass according to claim 2, comprising the following steps: (1) preparing a titanium dioxide mixed target for sputtering: adding tungsten trioxide to titanium dioxide, mixing, and then sintering at high temperature, the molar ratio of tungsten to titanium is 1 : 19～49; (2) clean the glass surface; (3) utilize magnetron sputtering to sputter nano-silicon dioxide film on the glass surface; (4) in the presence of nitrogen and argon, utilize magnetron sputtering to A mixed target of tungsten trioxide and titanium dioxide is sputtered on the surface of the silicon film; (5) the glass coated with double-layer film is annealed at 500-600° C. for 3-5 hours, and then cooled naturally in a sintering furnace.

4. The preparation method according to claim 3, characterized in that the magnetron sputtering in step (3) is radio frequency reactive magnetron sputtering, the sputtering target is a pure silicon dioxide target, and the sputtering atmosphere is pure argon gas, and the temperature of the glass substrate is 100-150°C. The obtained nano silicon dioxide film has a thickness of 20-30nm.

5. The preparation method according to claim 3, characterized in that the sputtering power of the titanium dioxide mixed target in step (4) is 180-250W, and the sputtering time is 3-8 hours; the sputtering atmosphere is nitrogen and The volume ratio of the argon gas is 0.5-1 according to N ₂ /(N ₂ +Ar), and the working pressure of the sputtering reaction is 0.8-1.5 Pa. The obtained doped titanium dioxide film has a thickness of 30-80nm.

6. The preparation method according to claim 3, characterized in that the heating rate of the annealing sintering furnace in step (5) is kept at 1°C/min.