纳米——ZnFe_2O_4/SiO_2上环己烷催化氧化反应的影响因素     

李纪连 《大连教育学院学报》2001,17(4):54-55

介绍了用纳米———ZnFe2 O4/SiO2 半导体材料作光催化剂 ,用分子氧催化氧化环己烷的实验 ,根据目前所建立的半导体粒子光催化反应机理的模式 ,探讨了其反应机理 ,并进一步研究了水分子以及电子或空穴捕获剂对该反应的影响。  相似文献   

TbFeO_3纳米晶的制备及其光催化活性     

刘清玲  岳小欣 《新乡师范高等专科学校学报》2006,20(5):36-38

以Tb4O7、Fe(NO3)3.9H2O、硝酸(1:1)为原料,在柠檬酸体系中用溶胶凝胶法合成了具有钙钛矿结构的稀土复合氧化物TbFeO3;用XRD、TEM对产物的组成、颗粒、大小、形貌进行了表征;结果表明,产物为纳米颗粒,平均粒径为21 nm左右,且颗粒均匀。另外以TbFeO3为光催化剂,对多种水溶性染料进行了光催化降解,发现TbFeO3有较好的光催化效果。实验表明,在无光照条件下,TbFeO3的脱色效果初期较明显,但效果达到一定程度后不再明显,并且随时间的推移,甚至有所下降。在光照条件下,TbFeO3的脱色效果初期短时间内就特别明显,最后接近100%.  相似文献   

层状复合金属氧化物光催化材料的结构与光谱响应特征     

何杰  刘晓天 《六安师专学报》2014,(5):70-75

由金属复合氧化物组成的层状材料,包括铌酸盐、钛酸盐、钛铌酸盐等,因其独特的结构和性质使其成为一种新型光催化材料而被广泛研究。通过调节层板组成、结构以及层间离子等可调变其光催化性能,通过插层（柱撑）、剥离组装等可形成丰富的光催化功能材料。本文就该方向的研究做一简要探讨,为进一步构建新型光催化材料提供参考。  相似文献   

碳掺杂量对C-Ce-TiO2光催化活性的影响     

龚丽芬  谢晓兰 《三明高等专科学校学报》2013,(6):5-8

以钛酸丁酯、四丁基氢氧化铵、硝酸铈为原料,采用溶胶一凝胶法合成C—Ce—TiO2光催化剂,经XRD、UV—Vis—DRS表征,在9W日光灯照射下光催化降解农药。结果表明：随着碳掺杂量的增加,微晶粒径减小、禁带能隙降低、对农药的光催化活性增大。  相似文献   

三氧化钨纳米线的制备及其光催化性能     

邹文雅  刘国聪 《惠州大学学报》2013,(6):18-23

以Na2WO4·2H2O和HCl为原料,采用水热法合成了WO3,并用x射线粉末衍射（XRD）、扫描电镜（SEM）、紫外漫反射（uV—Vis）、电子能量分散谱（EDS）和激光拉曼光谱（Raman）测试手段对样品进行表征。测试结果表明,Na2SO4作为添加剂时水热合成的产物皆为六方相三氧化钨纳米线,其粗细和长短略有差异,不同浓度的Na2SO4对产品晶型和形貌无影响,但影响其晶粒尺寸,其中0．125MNa2SO4所得六方相WO3纳米线的尺寸最小,平均直径约为5nm,长度约为1um,并具有最佳的光催化活性,可见光（≥420nm）照射150min罗丹明B溶液后的降解率达96．01％。  相似文献   

光催化氧化-分光光度法测定巢湖水体中的总氮     

叶友胜  万新军  程乐华 《黄山学院学报》2008,10(3)

用TiO2光催化氧化将巢湖水体中各种化合物含的氮转化为硝酸盐后用分光光度法进行定量测定,同时研究了各种光催化氧化反应条件对氮的降解率影响.结果表明该法的线性范围为0.00-0.35mg/L,检出限为2.55×10-3mg/L.  相似文献   

Ag2O/NaNbO3纳米复合材料的制备及其光催化性质     

李强  李世平  卢笑笑  马相东  韩浩  王康 《宜春学院学报》2020,(3):27-30

采用共沉淀法合成了Ag2O/NaNbO3复合光催化剂,并利用X射线衍射(XRD)和扫描电子显微镜(SEM)分别对其物相和形貌进行表征,用紫外可见漫反射光谱仪对其光学性质进行研究。在可见光下以罗丹明B(RhB)为目标降解物,检测了Ag2O/NaNbO3光催化剂的光催化性能。结果表明,与纯的Ag2O和纯的NaNbO3相比,Ag2O/NaNbO3复合光催化剂具有较高的光催化活性,其光催化活性的提升可能归结于p-n结的形成,使得光生电子空穴对的复合机率大大降低。  相似文献   

Integration of bio-inspired lanthanide-transition metal cluster and P-doped carbon nitride for efficient photocatalytic overall water splitting     

Rong Chen  Gui-Lin Zhuang  Zhi-Ye Wang  Yi-Jing Gao  Zhe Li  Cheng Wang  Yang Zhou  Ming-Hao Du  Suyuan Zeng  La-Sheng Long  Xiang-Jian Kong  Lan-Sun Zheng 《国家科学评论(英文版)》2021,8(9)

Photosynthesis in nature uses the Mn₄CaO₅ cluster as the oxygen-evolving center to catalyze the water oxidation efficiently in photosystem II. Herein, we demonstrate bio-inspired heterometallic LnCo₃ (Ln = Nd, Eu and Ce) clusters, which can be viewed as synthetic analogs of the CaMn₄O₅ cluster. Anchoring LnCo₃ on phosphorus-doped graphitic carbon nitrides (PCN) shows efficient overall water splitting without any sacrificial reagents. The NdCo₃/PCN-c photocatalyst exhibits excellent water splitting activity and a quantum efficiency of 2.0% at 350 nm. Ultrafast transient absorption spectroscopy revealed the transfer of a photoexcited electron and hole into the PCN and LnCo₃ for hydrogen and oxygen evolution reactions, respectively. A density functional theory (DFT) calculation showed the cooperative water activation on lanthanide and O−O bond formation on transition metal for water oxidation. This work not only prepares a synthetic model of a bio-inspired oxygen-evolving center but also provides an effective strategy to realize light-driven overall water splitting.  相似文献   

Influence of Calcination Temperature on TiO2 Nanotubes＇ Catalysis for TiO2/UV/O3 in Landfill Leachate Solution     

潘留明  季民  王秀朵  赵乐军 《天津大学学报(英文版)》2010,16(3):179-186

The influence of calcination temperature on TiO2 nanotubes＇ catalysis for TiO2/UV/03 was investigated. TiO2 nanotubes （TNTs） were prepared via the sol-gel method and calcined at 300--700 ℃, which were labeled as TNTs-300, TNTs-400, TNTs-500, TNTs-600 and TNTs-700, respectively. TNTs were characterized by transmission electron microscopy （TEM） and X-ray diffraction （XRD）. It is found that TNTs calcined at 400 ℃ showed the best thermal stability. When the calcination temperature increased from 400 ℃ to 700 ℃, the special structure of tubes was destroyed and gradually converted into nanorods and/or particles. The transformation from anatase to rutile occurred at 600 ℃, and the rutile phase was enhanced when the calcination temperature was increased to over 600 ℃. The calcina- tion temperature＇s influence on TNTs＇ adsorption activity for for TiO2/UV/O3 was investigated in landfill leachate solution chemical oxygen demand （COD） and catalytic activity In landfill leachate solution, the adsorption activity of COD decreased in the reduced order of TNTs-300, TNTs-400, TNTs-500, TNTs-600 and TNTs-700. In photocatalytic ozonation, TNTs-400 showed the best catalytic activity while TNTs-700 exhibited the worst. In other three processes, the COD removal of TNTs-300/UV/O3 was higher than those of TNTs-500/UV/O3 and TNTs-600/UV/O3 in the first 20 rain, and then became close to those of the latter two in the following 40 rain. Compared with TNTs-300 and TNTs- 400, TNTs-600 had the best anti-fouling activity, while TNTs-500 and TNTs-700 had lower anti-fouling activity than the former three. In photocatalytic ozonation, the calcination temperature of 400 ℃ was appropriate when TNTs were obtained at the synthesis temperature of 105 ℃.  相似文献   

1,3-双(芳基丁二烯基酮)丙烷衍生物的合成及其在 可见光诱导催化条件下的[4+4]和[2+2]环加成反应     

刘立强  杨镜奎 《中国科学院大学学报》2012,(2):180-191

合成了4种不同取代基的1,3-双(芳基丁二烯基酮)丙烷类新型双共轭链衍生物,并对其合成条件进行了优化,实施了其在可见光诱导Ru(bipy)₃Cl₂催化条件下发生的[4+4]和[2+2]环加成反应,合成得到了4个四环并五环及4个八环并五环双酮取代化合物. 该结果为合成特殊八员环及四员环类药物分子和多共轭有机光电材料化合物,提供了很好的前体化合物.  相似文献