甲基三乙氧基硅烷修饰的Ti^(3+)/SiO_2复合薄膜的发光性能  

Luminescence Properties of Ti^(3+) Doped Methyltriethoxysilane Modified SiO_2 Composite Coating

作　　者：蓝芳[1] 曹聪蕊[1] 肖波[1] 蒋晓东[2] 袁晓东[2] 江波[1] 

机构地区：[1]四川大学化学学院,成都610064 [2]中国工程物理研究院激光聚变研究中心,绵阳621900

出　　处：《高等学校化学学报》2008年第10期1921-1925,共5页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:10476012)资助

摘　　要：采用溶胶-凝胶(Sol-Gel)法,以正硅酸乙酯(TEOS)和甲基三乙氧基硅烷(MTES)为先驱物,盐酸为催化剂,用二步水解法制备了Ti3+/SiO2薄膜和甲基三乙氧基硅烷修饰的Ti3+/SiO2复合薄膜.采用红外光谱仪、X射线衍射仪、椭偏仪、荧光光谱仪等对膜层性质进行了分析.结果表明,掺杂Ti3+的SiO2薄膜分别在250 nm附近有一弱的激发峰,294 nm附近有一强的激发峰,在393 nm附近出现一强的发射峰.IR光谱发现,MTES修饰的Ti3+/SiO2复合薄膜的Si—OH的吸收峰强度比Ti3+/SiO2薄膜的略减小,Si—O—Si的吸收峰明显增强,表明复合薄膜硅氧网络结构更规则,有利于Ti3+的均匀分散.Ti3+/SiO2薄膜与复合薄膜的孔隙率分别为13.64%和6.66%,表明MTES的加入使薄膜更致密.在空气中陈放30 d后,Ti3+/SiO2薄膜已经检测不到荧光发射峰,而MTES修饰的Ti3+/SiO2复合薄膜荧光强度只下降了18%.在氮气中陈放30 d后,普通薄膜与复合薄膜的荧光强度均仅下降了10%.表明Ti3+的荧光猝灭的主要原因是由于Ti3+被氧化造成的.溶胶中加入MTES后,薄膜表面结构得到改善,有效地防止了Ti3+的氧化,荧光强度更稳定.Titanium trichloride doped silica coating modified by methyhriethoxysilane （MTES） was prepared by sol-gel method using two steps hydrolytic condensation with tetraethoxysilane （TEOS） and MTES as the precursors and hydrochloric acid as the catalyst. The properties of the coating were characterized with IR spectros- copy, X-ray diffractometer, spectroscopic ellipsometry and luminescence spectroscopy. The result showed that Ti^3＋ doped SiO2 coatings gave an excitation spectrum with two maxima, one at the wavelength of 250 nm, the other at the wavelength of 294 nm. Strong emission of Ti^3＋ doped SiO2 coatings was observed with a maximum at 393 nm. The Si--OH peak of MTES modified SiO2 composite coating is appreciably weaker and the Si--O--Si absoption peak is stronger than the normal Ti^3＋/SiO2 coating, which indicates that the silicon-oxygen network is improved by addition of MTES. Calculation results show that the porous ratio of the MTES mod- ified Ti^3 ＋/SiO2 composite coating was reduced from 13.64% to 6.66%, indicating that the composite coating is much more compact. When the samples were aged in air at 25 ℃ for 30 d, the fluorescence disappeared completely for normal Ti^3＋/SiO2 coating, while the fluorescence intensity of the MTES modified Ti^3 ＋/SiO2 composite coating was only reduced by 18%. When aged in N2 atmosphere at 25 ℃ for 30 d, the fluorescence intensities of both coatings were reduced by only 10%, Showing that the primary reason of fluorescence quenching is oxidization of Ti^3＋ . Addition of MTES in the sol can effectively improve the surface structure of SiO2 coating, which prevents Ti^3＋ from oxidization leading to a coating with stable fluorescence properties.

关 键 词：三氯化钛 甲基三乙氧基硅烷 二氧化硅薄膜 溶胶-凝胶 发光性能 

分 类 号：O613[理学—无机化学]