Functions and applications of the hottest nano tit

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Function and application of nano titanium dioxide

nano TiO2 has very valuable optical properties and shows a bright development prospect in the automotive industry and many fields. Nano titanium dioxide also has high chemical stability, thermal stability, non toxicity, super hydrophilicity, non migration, and can be completely in contact with food, so it is widely used in UV resistant materials, textiles, photocatalytic catalysts, self-cleaning glass, sunscreen, coatings, inks, food packaging materials, paper industry, aerospace industry

1. Sterilization function

under the action of ultraviolet light, ultra-fine TiO2 with a concentration of 0.1mg/cm3 can completely kill malignant Haila cells, and with the increase of the amount of superoxide dismutase (SOD), the efficiency of TiO2 photocatalysis to kill cancer cells is also improved; The advanced treatment of tap water with TiO2 photocatalytic oxidation can greatly reduce the number of bacteria in the water, and has no mutagenic effect after drinking, reaching the standard of safe drinking water. Adding nano titanium dioxide (the same as vk-tg01) to the paint can produce antibacterial and antifouling paint with sterilization, antifouling, deodorization and self-cleaning. It can be applied to hospital wards, Canada Magna multi lightweight materials to reduce the energy consumption of automobile life cycle by 16%. Places with dense bacteria and easy reproduction such as operating rooms and family toilets can effectively kill Escherichia coli, yellow glucose bacteria and other harmful bacteria and prevent infection. Therefore, nano titanium dioxide (the same as vk-tg01) can purify the air and has the function of deodorization

1) antibacterial characteristics of nano titanium dioxide (the same as vk-tg01):

1 is safe and non-toxic to human body and non irritating to skin

2 it has strong antibacterial ability and wide antibacterial range

3 no odor, strange smell, small odor

4 it is washable and has a long storage period

5 good thermal stability, no discoloration, decomposition, volatilization and deterioration under high temperature

6 has good immediacy. The effect of nano titanium dioxide antibacterial agent can be achieved in only 1H, while that of other silver antibacterial agents takes about 24h

7 nano titanium dioxide (the same as vk-tg01) is an antibacterial agent that permanently maintains the antibacterial effect

8 has good safety. It is used in food additives and has no adverse effect on skin contact

2) antibacterial principle of nano titanium dioxide (same as vk-tg01):

nano titanium dioxide (same as vk-tg01) decomposes bacteria under photocatalysis to achieve antibacterial effect. Because the electronic structure of nano titanium dioxide is characterized by a full TiO2 valence band and an empty conduction band, in the system of water and air, under the irradiation of sunlight, especially ultraviolet light, when the electron energy reaches or exceeds its band gap energy, the electrons can be excited from the valence band to the conduction band, and at the same time, corresponding holes are generated in the valence band, that is, electrons and hole pairs are generated. Under the action of electric field, electrons and holes are separated, Migrate to different positions on the particle surface, and a series of reactions occur:

tio2 + H ν E - - + H +

H2O + H + - OH + H +

O2 +e - - O-2

O-2 + H + - HO2

2ho2 - O2 + H2O2

H2O2 +o-2 - OH + OH - +o2

adsorb the oxygen dissolved on the surface of TiO2 and capture electrons to form O2. The generated superoxide anion radical reacts (oxidizes) with most organics. At the same time, it can react with organics in bacteria to produce CO2 and H2O; Holes oxidize oh and H2O adsorbed on the surface of TiO2 into oh. Oh has strong oxidation ability, attacks the unsaturated bond of organic matter or extracts H atoms to produce new free radicals, excites chain reaction, and finally causes bacteria to decompose

tio2's bactericidal effect lies in its quantum size effect. Although titanium dioxide (ordinary TiO2) also has photocatalysis and can produce electron and hole pairs, its time to reach the surface of the material is more than microseconds, so it is very easy to compound, and it is difficult to play the antibacterial effect. However, TiO2 with nano dispersion, the electrons and holes excited by light migrate from the body to the surface in nanoseconds, picoseconds, or even femtoseconds, The recombination of photogenerated electrons and holes is on the nanosecond scale, which can quickly migrate to the surface, attack bacterial organisms, and play a corresponding antibacterial role

nano titanium dioxide (the same as vk-tg01) has high surface activity, strong antibacterial ability, and the product is easy to disperse. Tests show that nano titanium dioxide (the same as vk-tg01) has a strong bactericidal ability against Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Salmonella and Aspergillus. It has been widely used in antibacterial products in textile, ceramics, rubber, medicine and other fields, and is deeply welcomed by a wide range of users

3) research and application examples of antibacterial properties of nano titanium dioxide at home and abroad

○ 1 farmland antibacterial agent: Japan has developed a new type of sterile bactericide. Its main components are nano silica (the same as vk-sp30), nano titanium dioxide (the same as vk-tg01) and silver and copper plasma. It can be used in soil and has strong antibacterial activity against all bacteria. The modified bactericide is a micro mixed metal ion of ceramics, and has the function of activating oxygen in soil under the action of catalyst containing the same ion. This function can last for up to years in the automotive industry

○ 2 sanitary ceramic sanitary ware: the sintering temperature of ceramics is very high, so only sterile antibacterial agents that are stable at high temperature can be added. Japan recently developed antibacterial ceramic products coated with nano silica. Its manufacturing process is to first summarize the simple quality and price of nano titanium dioxide (same as vk-tg01) into a slurry made of water and coated on the ceramic surface, and then sinter it at high temperature to obtain a 1 micron thick photocatalytic nano titanium dioxide (same as vk-tg01) film product. Under light irradiation, the bacteria on its surface can be completely killed. Trace amounts also have antibacterial properties under weak light. Silver and copper plasma compounds can be added to nano titanium dioxide slurry. This kind of ceramic has good durability, acid and alkali resistance. It is an ideal ceramic for antibacterial and deodorization in medicine, hotels, family bathtubs, floor tiles, sanitary facilities and so on

○ 3 water treatment: researchers at the University of Texas in the United States use nano titanium dioxide (the same as vk-tg01) and sunlight for sterilization. They exposed the mixture of E. coli and nano titanium dioxide (with vk-tg01) to light greater than 380nm and found that E. coli was quickly killed. This technology may become an alternative technology for water treatment by chlorination at present

○ 4 new antibacterial fluorescent lamp: Japan made and developed a new information fluorescent lamp with antibacterial effect, which was commercialized in 1997. This kind of lamp has long service life, energy saving and broad application prospects. These surfaces are coated with photocatalytic bactericide nano titanium dioxide (the same as vk-tg01), which can decompose the oil stains on the surface and the fungus odor in the air. Sweeping victory, and has the effect of preventing the light from dimming

○ 5 antibacterial fibers: antibacterial fibers and deodorizing fibers are functional fibers of information. These are micro powders such as nano titanium dioxide, nano silicon dioxide (the same as vk-sp30), nano zinc oxide (the same as vk-js03) are mixed into natural and artificial polymers or filaments, and then various antibacterial and deodorizing fibers are spun. Antibacterial fiber has excellent health care function

○ 6 antibacterial building materials and antibacterial coatings: it is reported that antibacterial titanium can kill the surrounding bacteria, and has the functions of antibacterial, rust prevention, decomposition of odor, antifouling, and reduction of nitrogen dioxide content. It can not only decompose and eliminate the formaldehyde produced by new building materials and adhesives in the room, acetaldehyde produced by smoking, methyl mercaptan and other organic odors produced by household dust under UV irradiation, but also decompose oil and organic surface pollution. The oil film can be significantly reduced after 3 days of irradiation, and no trace will be left after 5 days of irradiation. The color of organic dyes will fade after 3 days of irradiation. Using this property, antibacterial titanium can be used as decorative materials for outer and inner walls

bacteria are often attached to the roof and exterior walls of buildings, operating tables and walls of hospital operating rooms. If photocatalysis nano titanium dioxide coating or wall tiles are painted, the bacteria can be quickly destroyed under sunlight or weak indoor light. Moreover, the rainwater scouring Department washes away the dirt after oxidation and decomposition at any time

○ 7 killing oral microorganisms: nano titanium dioxide can kill tans strain AHT (serotype), hamster Streptococcus sh-6, rat Streptococcus FA-1 and actinomycete viscosus atcc-19246. The research shows that the finer the particle size, the better the dispersion and the larger the specific surface area of nano titanium dioxide (the same as vk-tg01), the better the sterilization effect

2.2 UV protection function

nano titanium oxide (the same as vk-t25) can not only absorb UV, but also reflect and scatter UV, but also pass through visible light. It is a physical shielding UV protective agent with superior performance and great development prospects

anti ultraviolet mechanism of nano titanium oxide (the same as vk-t25):

according to different wavelengths, ultraviolet rays are divided into short wave region 190 ~ 280 nm, medium wave region 280 ~ 320 nm, and long wave region 320 ~ 400nm. The ultraviolet energy in the short wave region is the highest, but it is blocked when passing away from the ozone layer. Therefore, ultraviolet rays in the medium wave region and long wave region are generally harmful to human body

the strong UV resistance of nano titanium oxide (the same as vk-t25) is due to its high refractive index and high photoactivity. Its anti ultraviolet ability and its mechanism are related to its particle size: when the particle size is large, the barrier to ultraviolet rays is mainly reflection and scattering, and it is effective for ultraviolet rays in medium wave region and long wave region. The sunscreen mechanism is simple covering, which belongs to general physical sunscreen, and the sunscreen ability is weak; With the decrease of particle size, light can pass through the particle surface of nano titanium dioxide (the same as vk-t25), and the reflection and scattering of UV in the long wave region are not obvious, while the absorption of UV in the medium wave region is significantly enhanced. Its sunscreen mechanism is to absorb ultraviolet rays, mainly ultraviolet rays in the medium wave area

it can be seen that the sunscreen mechanism of nano titanium oxide (the same as vk-t25) for different wavelengths of ultraviolet rays is different. The barrier to ultraviolet rays in the long wave region is mainly scattering, and the barrier to ultraviolet rays in the medium wave region is mainly absorption

nano titanium oxide (same as vk-t25) shows excellent absorption performance in different wavelength regions. Compared with other organic sunscreen agents, nano titanium oxide (same as vk-t25) has the characteristics of non-toxic, stable performance and good effect. Shiseido Japan uses nm nano titanium dioxide (the same as vk-t25) as a sunscreen ingredient added to lipstick and face cream, and its sunscreen factor can increase SPF

nano titanium dioxide (the same as vk-t25) has stronger barrier ability to ultraviolet rays because of its small particle size and high activity, which can not only reflect and scatter ultraviolet rays, but also absorb ultraviolet rays. Compared with some organic UV protectors with the same dose, nano titanium oxide (the same as vk-t25) has a higher absorption peak in the UV region. What is more valuable is that it is also a broad-spectrum shielding agent, which does not only absorb UVA or UVB like organic UV protectors. It can also pass through visible light, and when added to cosmetics, the skin whiteness is natural. Unlike pigment grade TiO2, it cannot pass through visible light, resulting in unnatural pale color on the user's face

using the transparency and UV absorption capacity of nano TiO2, it can also be used as food packaging film, ink, coating, textile products and plastic filler, which can replace organic UV absorber and improve the aging resistance of coating when used in coating

2.3 photocatalytic function

nano titanium dioxide prepared by liquid phase method has the characteristics of less particle agglomeration, high chemical activity, narrow particle size distribution, uniform morphology and so on. It has strong photocatalytic performance and has been widely used in environmental protection

(1) gas purification


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