Study On The Preparation Of Fe₂O₃/TiO₂and SiO₂/TiO₂Composite Photocatalyst Via Microemuision Method And Their Properties

To overcome some disadvantages of single TiO2photocatalyst such as lower photocatalyticactivity, short surface area and high cost, improve its activities and lower the cost, theFe₂O₃/TiO₂and SiO₂/TiO₂composite photocatalyst were prepared by microemulsion methodusing inorganic polymerized silicate as the silicon source, iron nitrate as the iron source and titaniumsulfate as the titanium source.By using methyl orange as the main object of photocatalytic degradation, the influences ofdifferent microemulsion systems, raw material proportioning and the conditions of heat treatmenton the properties of Fe₂O₃/TiO₂and SiO₂/TiO₂photocatalyst were investigated, and thephotocatalysts were characterized by SEM，FTIR，XRD and BET. The results showed that theFe₂O₃/TiO₂and SiO₂/TiO₂composite photocatalysts prepared at the best conditions were tinyparticles with loose textured surface. The specific surface area of them was60.3m²/g and74.1m²/g respectively. The decoloration rate of methyl orange under UV light irradiation for15minutes by SiO₂/TiO₂and Fe₂O₃/TiO₂could reach90%. The crystalline phase of these twocomposite photocatalysts is in the coexistence of a great deal of anatase and a little rutile. Thecompound of SiO2and Fe2O3inhibited the crystal phase transformation from anatase into rutileeffectively under the thermal treatment of higher temperature.. The composite photocatalystshave higher specific surface area, better photocatalytic activity and stronger thermal stabilitythan the TiO2photocatalyst prepared under the same condition.