(江蘇大學(xué) 化學(xué)化工學(xué)院，鎮(zhèn)江 212013)
摘 要: 研究以硅酸鈉為原料，利用液相沉積法在以硫酸氧鈦為原料制備的金紅石型二氧化鈦表面包覆二氧化硅納米膜。使用透射電鏡分析二氧化鈦表面二氧化硅包覆膜的形貌，結(jié)合紅外光譜與X射線光電子能譜分析技術(shù)研究金紅石型二氧化鈦表面包覆二氧化硅納米膜的成膜過程以及成膜機理。以激光粒度測定儀分析二氧化硅包覆二氧化鈦樣品在水溶液中的分散程度。實驗表明，二氧化硅包覆層與基底二氧化鈦之間存在Si—O—Ti鍵。將反應(yīng)液pH值控制在不同的范圍內(nèi)可以在二氧化鈦顆粒表面包覆不同形貌的二氧化硅包覆層，形成島狀膜或連續(xù)致密膜。粒徑分析表明二氧化硅包覆能夠很好地提高二氧化鈦的分散程度。
關(guān)鍵字: 二氧化鈦；二氧化硅；納米膜；島狀包覆；致密包覆
（Faculty of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, China）
Abstract:SiO2-coated TiO2 powders were prepared by chemical deposition method starting from rutile TiO2 and Na2SiO3. The SiO2-coated TiO2 powders were characterized by X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy and laser particle size instrument. The formation mechanism of the nanosilica film on TiO2 surface was investigated. The silica coating layers were anchored on TiO2 surfaces via the Ti—O—Si bonding at the interface. The evolution of island-like coating and uniform coating layers depend upon reaction temperature and pH. After coating, the dispersibility of SiO2-coated TiO2 powders in water is promoted.
Key words: TiO2; SiO2; nanofilm; island coating; uniform coating
