Sunlight-driven C-TiO2/FeTiO3 composites were synthesized with different weight fractions of FeTiO3. The as-prepared samples were characterized by UV-Visible diffuse reflectance spectroscopy, Fourier transform infrare...Sunlight-driven C-TiO2/FeTiO3 composites were synthesized with different weight fractions of FeTiO3. The as-prepared samples were characterized by UV-Visible diffuse reflectance spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction analysis, transmission electron microscopy, scanning electron microscopy, energy-dis- persive X-ray spectroscopy, and photoluminescence. Under sunlight irradiation, the C-TiO2/FeTiO3 photocatalysts degraded methyl orange （MO） efficiently and displayed much higher photocatalytic activity than that of pure FeTiO3 or carbon-doped titanium dioxide （C-TiO2）, and the C-TiOE/FeTiO3 photocatalyst with 10 wt% of FeTiO3 exhibited the highest photocatalytic activity. The enhancement of photocatalytic activity was mainly ascribed to the formation of a heterojunction between C-TiO2 and FeTiO3, which facilitated the transfer and separation of photogenerated electron-hole pairs. The quenching effects of different scavengers demonstrated that the reactive superoxide radicals （02-） and hydroxyl radicals （OH） played a major role in the MO degradation. The possible photocatalytic mechanism is discussed on the basis of the band structures of C-TiO2 and FeTiO3. To further enhance the photocatalytic efficiency, double-heterojunctioned CQD/C-TiO2/FeTiO3 composite was prepared by loading carbon quantum dots onto the C-TiO2/FeTiO3 surface.展开更多
以TiCl_3(3THF)为原料合成脒基钛(Ⅲ)配合物1,将其作为前驱体通过LPCVD沉积N/C-TiO_2薄膜。利用1HNMR、元素分析以及热重分析(TGA)探究配合物1的结构和热化学性质。结果表明,配合物1具有良好的热稳定性和合适的挥发性,满足CVD的要求。通...以TiCl_3(3THF)为原料合成脒基钛(Ⅲ)配合物1,将其作为前驱体通过LPCVD沉积N/C-TiO_2薄膜。利用1HNMR、元素分析以及热重分析(TGA)探究配合物1的结构和热化学性质。结果表明,配合物1具有良好的热稳定性和合适的挥发性,满足CVD的要求。通过EDS和UV-Vis吸收光谱表征了薄膜的成分及光学性能,结果表明,当沉积温度为350℃时,N/C-TiO_2薄膜的N、C质量分数最高,其禁带宽度降低为2. 82 e V,对可见光的吸收最强。与纯的二氧化钛薄膜相比,N/C-TiO_2薄膜对亚甲基蓝的降解率显著提高到90%。展开更多
针对BOTDR分布式光纤传感技术中背向散射光中布里渊散射信号光的分离提取问题,设计了一种高消光比双通道可调M-Z干涉仪,该干涉仪由两个3 d B耦合器、电动光纤延迟线、偏振控制器及光隔离器构成。使用C波段宽带光源(ASE)对M-Z干涉仪性能...针对BOTDR分布式光纤传感技术中背向散射光中布里渊散射信号光的分离提取问题,设计了一种高消光比双通道可调M-Z干涉仪,该干涉仪由两个3 d B耦合器、电动光纤延迟线、偏振控制器及光隔离器构成。使用C波段宽带光源(ASE)对M-Z干涉仪性能进行了检测。并将脉宽为100 ns,重复频率为20 k Hz的脉冲光入射到长度为5 km的普通单模光纤中,将其产生的背向散射光经过M-Z干涉仪滤波后,通过光谱仪检测其输出的光谱信号。实验结果表明该干涉仪能够实现大范围高精度可调节滤波功能,对瑞利散射光的抑制超过20d B,可以有效地将背向散射光中的布里渊散射光信号分离提取出来。展开更多
基金the University Grants Commission(UGC), New Delhi,India,for financial support with Ref.No.:17-06/ 2012(i)EU-V
文摘Sunlight-driven C-TiO2/FeTiO3 composites were synthesized with different weight fractions of FeTiO3. The as-prepared samples were characterized by UV-Visible diffuse reflectance spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction analysis, transmission electron microscopy, scanning electron microscopy, energy-dis- persive X-ray spectroscopy, and photoluminescence. Under sunlight irradiation, the C-TiO2/FeTiO3 photocatalysts degraded methyl orange （MO） efficiently and displayed much higher photocatalytic activity than that of pure FeTiO3 or carbon-doped titanium dioxide （C-TiO2）, and the C-TiOE/FeTiO3 photocatalyst with 10 wt% of FeTiO3 exhibited the highest photocatalytic activity. The enhancement of photocatalytic activity was mainly ascribed to the formation of a heterojunction between C-TiO2 and FeTiO3, which facilitated the transfer and separation of photogenerated electron-hole pairs. The quenching effects of different scavengers demonstrated that the reactive superoxide radicals （02-） and hydroxyl radicals （OH） played a major role in the MO degradation. The possible photocatalytic mechanism is discussed on the basis of the band structures of C-TiO2 and FeTiO3. To further enhance the photocatalytic efficiency, double-heterojunctioned CQD/C-TiO2/FeTiO3 composite was prepared by loading carbon quantum dots onto the C-TiO2/FeTiO3 surface.
文摘以TiCl_3(3THF)为原料合成脒基钛(Ⅲ)配合物1,将其作为前驱体通过LPCVD沉积N/C-TiO_2薄膜。利用1HNMR、元素分析以及热重分析(TGA)探究配合物1的结构和热化学性质。结果表明,配合物1具有良好的热稳定性和合适的挥发性,满足CVD的要求。通过EDS和UV-Vis吸收光谱表征了薄膜的成分及光学性能,结果表明,当沉积温度为350℃时,N/C-TiO_2薄膜的N、C质量分数最高,其禁带宽度降低为2. 82 e V,对可见光的吸收最强。与纯的二氧化钛薄膜相比,N/C-TiO_2薄膜对亚甲基蓝的降解率显著提高到90%。
文摘针对BOTDR分布式光纤传感技术中背向散射光中布里渊散射信号光的分离提取问题,设计了一种高消光比双通道可调M-Z干涉仪,该干涉仪由两个3 d B耦合器、电动光纤延迟线、偏振控制器及光隔离器构成。使用C波段宽带光源(ASE)对M-Z干涉仪性能进行了检测。并将脉宽为100 ns,重复频率为20 k Hz的脉冲光入射到长度为5 km的普通单模光纤中,将其产生的背向散射光经过M-Z干涉仪滤波后,通过光谱仪检测其输出的光谱信号。实验结果表明该干涉仪能够实现大范围高精度可调节滤波功能,对瑞利散射光的抑制超过20d B,可以有效地将背向散射光中的布里渊散射光信号分离提取出来。
