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以钛酸丁酯为原料,冰醋酸为抑制剂,无水乙醇为溶剂,采用溶胶凝-胶法制备了TiO_2,对其进行了450℃不同保温时间的退火处理。利用XRD、SEM、EDS、XPS等测试技术对样品进行晶型、形貌、元素组成及价态的表征。结果表明,不同保温时间退火处理的TiO_2都生成了锐钛矿,随保温时间增加晶粒尺寸与晶型完整度增加;TiO_2颗粒呈现近似球形形貌。以亚甲基蓝为目标污染物,考察了样品的光催化效率,结果表明,保温1h的TiO_2具有最大的降解率与反应速率常数,光照3h后,其降解率达到80.9%,反应速率常数为0.562h-1。
TiO 2 was prepared by sol - gel method using butyl titanate as raw material, glacial acetic acid as inhibitor and anhydrous ethanol as solvent. The samples were annealed at 450 ℃ for different holding time. The samples were characterized by XRD, SEM, EDS and XPS. The crystal structure, morphology, elemental composition and valence of the samples were characterized. The results show that anatase is formed on TiO_2 annealed at different holding time, and the grain size and the crystallinity increase with the increase of holding time. The TiO_2 particles exhibit approximately spherical morphology. The photocatalytic efficiency of the sample was investigated with methylene blue as the target pollutant. The results showed that the TiO 2 with the best thermal stability for 1 h had the highest degradation rate and reaction rate constant, the degradation rate was 80.9% and the reaction rate constant was 0.562 h- 1.