【摘要】 采用液相沉积法在纳米TiO2表面沉积SiO2形成SiO2-TiO2纳米复合微粒,然后用γ-氨丙基三乙氧基硅烷(KH-550)对SiO2-TiO2微粒进行表面部分修饰,制备了两亲性TiO2界面光催化剂。采用XRD、TEM、FT-IR和TG-DTA等技术研究了所得样品的形态结构和包覆情况。结果表明,SiO2-TiO2复合微粒中TiO2呈锐钛矿型,且其表面均匀地包覆着一层SiO2膜,对SiO2-TiO2纳米复合微粒进行部分改性后,所得样品具有界面两亲性质,紫外光照射2 h后仍能够稳定地悬浮在油-水两相界面。以亚甲基蓝的光催化降解反应为模型反应,考察了TiO2界面光催化剂的催化性能,试验结果表明,在紫外光照射下,TiO2界面光催化剂对亚甲基蓝的脱色降解效果明显优于纯TiO2,反应2 h后脱色率达到75%左右;并且TiO2界面光催化剂由于可以稳定悬浮于界面上而便于回收。更多还原

【Abstract】 A new catalyst of TiO2 phase-boundary catalyst was prepared by first precipitation of SiO2 on the surface of TiO2 via chemical deposition in aqueous solution method,then the surfaces of SiO2-TiO2 were modified by the partial alkylsilylation of γ-Aminopropyltriethoxysilane to render the SiO2-TiO2 surface amphiphilic.The as-prepared catalysts were characterized by using XRD,HR-TEM,FT-IR and TG-DTA techniques.Results demonstrated that,as-prepared catalysts could be easily located at the boundary of the dual-phase organic-water mixture,due to the introduction of partial hydrophobicity.By using the degradation of methylene blue as the model reaction,the photocatalytic property of the TiO2 phase-boundary catalyst was investigated.Results indicated that photocatalytic activity was much better than that of bare TiO2.Furthermore,TiO2 phase-boundary catalyst could be easily recovered due to its stable floatability.更多还原