Preparation And Properties Of TiO₂ Thin Films

Because of its low cost, non-toxic, high catalytic activity, good stability, ease ofrecycling, and other properties , TiO₂has become more and more widely.It is considered to beideal photocatalyst. In order to improve the photocatalytic properties and reuse capability onTiO₂, in recent years researchers have been working at home and abroad preparation andproperties of the thin film structure of TiO₂. The specific morphology of TiO₂compared withthe general TiO₂powder has a unique structure, performance, use of a wide range of manyfeatures of the acclaimed. This paper focuses on two different electrochemical preparation ofTiO₂thin films. It is preliminarily characterization of some chemical properties of theproduct.When researched the TiO₂Films ,it is prepared by anodic oxidation. The main factor isacetic acid content, reaction temperature, （NH₄）₂SO₄ content, applied voltage, and thereaction time.With the experiments, the impact of efforts on the film from high to low iscontent of aceticacid,oxidation voltage of （NH₄）₂SO₄content,temperature,reaction time. Thebest ratio is at 23℃, the electrolyte in acetic acid environment under the 3 mol / L （NH4）2SO4and 0.5% KF mixed solution in the 20V external DC voltage, the oxidation time of 2h,and burned in a muffle furnace at 30min, repeated four times. Under the optimum conditions,TiO₂Thin Films degradate methyl orange up to 99%.When researched the TiO₂films ,it is prepared by the cathodic deposition. Twomorphologies of TiO₂is attained in the same time.It is the film and the particles,and the twoforms of them has the degradation effect of methyl orange wastewater.Sulfuric acid has thegreatest impact on TiO₂grain, in the same conditions ,under ultraviolet light irradiation in thesame time, photocatalytic acid the amount of for 1mL time catalytic best performance. After50 minutes when the photocatalytic, photocatalytic degradation of different particles arebasically completed, and the degradation rate is closed to 100%. The different thing is onlythe beginning of half time catalytic efficiency. TiO₂thin films, the influence of concentrated sulfuric acid is not very big, the photocatalytic effect of a variety of products are relativelyclose, after half an hour in about 90%. Degradation rate and particulate membrane catalyticperformance is much better than the catalytic properties of the particles.Cathodic deposition method, distilled water one-time quickly to join after all a productof both TiO₂particles, changing the content of concentrated sulfuric acid, the yield is identical,about 80%. Concentrated sulfuric acid only change the particle size and morphology of thefilms, and has no effect on the yield, the formation of particles and it contrast to the particlesby electrolytic method, no significant change of particle size, but has a geat influeence to thethe photocatalytic efficiency. Cathodic Deposition of particles, the photocatalytic efficiencyabout 60% higher than that of pure particles.HMX wastewater processing is preliminary studied with the long-term placement inlast part. The HMX, which is toxic,high concentration,refractory wastewater ,is dealing withstep-by-step. HMX wastewater treatment, to go out of its pungent odor, followed by increaseof its BOD values, and finally to reduce the COD value. After testing, training, yeast is addedto the HMX thermostat can increase its BOD values; zero-valent iron reduction and noteffective in a significant reduction in COD, but NO₂-restore of NH₂-and greatly reduce thetoxicity of nitro compounds, and can activate the benzene ring, because the NH2-reactivegroups; addition, ferrous ions into the conduct of the Fenton reaction ready, advancedoxidation reaction. Of HMX wastewater is not reached to the emission standards for B / Cgreater than 0.3, the BOD value from 0 mg/L change to 45 mg/L,COD value was reducedfrom 14000 mg/L to 1100 mg/L.Achieve the purpose of preliminary treatment.