共查询到20条相似文献,搜索用时 156 毫秒
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采用共沉淀法合成了纳米级钙钛矿型复合氧化物CeFeO3。通过X射线衍射(XRD)、透射电镜(TEM)等分析手段对制得粉体的粒径、物相、形貌进行了表征。在多功能光催化反应仪中,以多种水溶性染料包括活性翠蓝KGL、活性艳蓝KGR、活性艳红X-3B、活性橙K3N等的光催化降解为模型反应,通过粉体对水溶性染料的降解情况对材料的光催化活性进行了测试,结果显示纳米级CeFeO3显示较好的光催化活性。 相似文献
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TiO2 纳米薄膜微结构及光催化性能研究 总被引:4,自引:0,他引:4
以钛酸丁酯Ti(OBu)4为原料,采用溶胶-凝胶法在普通钠钙玻璃表面制备了TiO2纳米薄膜,用XRD、UV-VIS等技术对薄膜微结构及紫外吸收性能进行了表征,选用食用油光催化降解为模型对TiO2薄膜光催化性能进行了评价。探讨了退火温度对薄膜晶相结构及其光催化活性的影响,450℃退火处理的薄膜呈锐钛矿和金红石型混晶结构,锐钛矿相平均晶粒尺寸为28.8 nm,金红石相平均晶粒尺寸为40.4 nm,700℃退火后为纯金红石相。焙烧温度在450—490℃光催化活性较为理想,480℃附近光催化活性达到最高。涂膜层数增加,光催化活性增强,8层膜的光催化活性最高。 相似文献
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以硝酸锌、柠檬酸、尿素为原料,通过水热法,制得了掺杂了不同含量的稀土Ce的纳米氧化锌的前驱体。通过在不同温度下煅烧纳米氧化锌前驱体,得到目标产物。进而以亚甲基蓝(MB)为目标降解物,对纳米氧化锌的光催化活性进行研究,考察了铈的不同掺杂量和不同的煅烧温度对于ZnO的光催化活性的影响。同时对样品进行了热重、透射电子显微、傅里叶红外的表征。实验结果表明,稀土掺杂量为2%,焙烧温度为400℃的ZnO的光催化活性较好,颗粒接近球形。 相似文献
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液相沉积法制备光催化TiO2/SiO2复合薄膜及其表征 总被引:8,自引:0,他引:8
通过液相沉积法在较低的温度下制备了TiO2/SiO2复合薄膜,利用UV-Vis、XRD和SEM等表征手段对薄膜的透明性、物相和表面形貌进行了表征;并在紫外光照下,通过薄膜对罗丹明B水溶液的光催化降解实验,评价了沉积薄膜的光催化活性。实验结果表明,在室温下制备的液相沉积膜具有较好的光催化活性。 相似文献
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采用悬浆外照式光催化反应器,研究了在紫外光照下低活性颜料二氧化钛光催化降解罗丹明B的反应动力学特性。考察了二氧化钛浓度、罗丹明B浓度、紫外线波长及光强对光催化反应速率的影响,确定了适合颜料二氧化钛光催化特性评价的优化检测条件。研究表明,颜料二氧化钛光催化降解罗丹明B具有一级反应动力学特性。确定颜料二氧化钛光催化特性检测方法的优化操作条件为二氧化钛浓度约为4 g·L-1、罗丹明B浓度为2~10 mg·L-1、紫外光源主发射波长为254 nm。实验检测了表面包硅二氧化钛样品的光催化特性,表明该检测方法能够对颜料二氧化钛及包膜二氧化钛的光催化特性进行快速定量的评价。 相似文献
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镍掺杂对二氧化钛光催化性能影响的研究 总被引:5,自引:0,他引:5
采用溶胶-凝胶法制备了纳米二氧化钛以及不同掺镍量的TiO2纳米粒子(原料中Ni∶TiO2的摩尔分数为1%、3%、5%、7%、9%)。用紫外光照射甲基橙溶液的光催化降解实验研究了掺镍对二氧化钛光催化剂催化效率的影响,试验结果表明,当用n(Ni)∶n(TiO2)=5%的Ni(NO3)2溶液进行镍掺杂时,制得的TiO2催化剂光催化效率最高,但与纯TiO2相比,镍掺杂会减弱TiO2的光催化效率。X射线衍射分析表明,未掺杂的TiO2以锐钛矿和金红石两种晶型混合存在,镍掺杂后TiO2的晶型几乎全为锐钛矿。镍掺杂后会减小TiO2粒子的尺寸,增大其比表面积。 相似文献
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对纳米TiO2去除水中铬离子进行了研究,并对反应条件对金属离子脱除率的影响进行了系统的讨论。研究结果表明,对于铬离子体系,pH值越小,其光催化效果越显著。此外,EDTA的添加有助于有效地去除铬离子。 相似文献
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采用简单的热蒸发法,调控温度与催化剂制备了ZnO微/纳米材料,通过扫描电子显微镜(SEM)和X-射线衍射(xRD)对产物的结构和形貌进行了表征,并以甲基橙溶液为光催化反应模型降解物,考察了样品的光催化活性。结果显示,ZnO微/纳米材料为六角纤锌矿结构,Ni(NO3)2催化剂的存在对不同温度下生成的ZnO光催化效率有较显著影响。 相似文献
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《Ceramics International》2016,42(8):9963-9971
The purpose of the present study is to prepare palladium-supporting porous titania particles via a sol–gel process using an inkjet nozzle and to improve the photocatalytic activity of the particles. The morphology of titania particles produced by the sol–gel process using an inkjet nozzle was evaluated by scanning electron microscopy and nitrogen physisorption measurements. The photocatalytic activity of the obtained titania particles was evaluated using the changes in the concentration of a methylene blue solution under UVC light irradiation and the effect of palladium supported on the inner and outer surfaces of the titania particles on the photocatalytic activity was investigated.The titania particles prepared by inkjet processing exhibited spherical porous structures. The particle and pore size distributions of the obtained titania particles were more uniform than those of the titania particles prepared using the non-inkjet nozzle. The titania particles supporting palladium on the inner and outer surfaces exhibited a faster rate of photocatalytic degradation than the titania particles supporting palladium on only the outer surface, with anatase titania particles exhibiting the highest rate of photocatalytic degradation. Thus, we have successfully improved the photocatalytic activity of titania particles by supporting palladium on the inner and outer titania surfaces. This sol–gel process using an inkjet nozzle is an effective method for the preparation of porous titania particles supporting palladium on their inner and outer surfaces. 相似文献
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掺镧纳米TiO2的光催化性能研究 总被引:5,自引:1,他引:5
研究了掺镧纳米TiO2的物理特性及光催化活性,探讨了它们之间的关系,通过对甲基橙和罗丹明两种不同结构物质的降解实验,发现掺镧纳米TiO2光催化性能具有广泛性。用于实际印染废水处理,再次验证掺镧能提高TiO2的光催化效能,掺镧摩尔分数为0.02%时光催化效果最好。 相似文献
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Anirban Chowdhury Akira KudoTakeshi Fujita Ming-Wei ChenTadafumi Adschiri 《The Journal of Supercritical Fluids》2011,58(1):136-141
Nano-TiO2 crystals showing visible light driven photocatalytic activity were synthesized by hydrothermal reaction in an ethanol-water mixture. The experiments were conducted to optimise the synthesis conditions for nano titania, in the range of temperature from 200 to 400 °C. X-ray diffraction depicted that the products obtained were anatase at 250 °C and above. For the products obtained at 250 °C, detailed analysis was conducted since it depicted high crystallinity with smallest particle sizes. Shape of the crystal was rounded rectangular with the size of 4 ± 1 nm to 7 ± 1 nm. The high-resolution transmission electron microscopy (HRTEM) revealed the existence of novel nano-twin structure in anatase grains and surface defects around the nanocrystals. Photocatalytic property was investigated for these undoped titania samples under UV and visible light. The nano twin structure, surface defects, and nano-meter size of the synthesized titania are believed to play a crucial role for the high catalytic activity. 相似文献
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K. V. Baiju A. Zachariah S. Shukla S. Biju M. L. P. Reddy K. G. K. Warrier 《Catalysis Letters》2009,130(1-2):130-136
Mixed-phase nanocrystalline titania with varying rutile-content has been synthesized via solvent mixing and calcination treatment of sol–gel derived nanocrystalline anatase and rutile precursors. The mixed-phase nanocrystalline titania has been characterized using different analytical techniques for analyzing their phase contents, nanocrystallite size distribution, band-gap, and photoluminescence. The photocatalytic activity of mixed-phase nanocrystalline titania has been studied by monitoring the degradation of methylene blue dye in an aqueous solution under ultraviolet-radiation exposure. A strong correlation between photoluminescence and photocatalytic activity has been demonstrated for the mixed-phase nanocrystalline titania. 相似文献