文摘辑要

电化学制备TiO2多孔纳米薄膜的影响因素研究 以硫酸溶液为电解液,用阳极氧化方法制备出具有纳米孔结构氧化钛薄膜,光催化性能远远大于普通尺度的氧化钛,通过在氧化钛表面附载卟啉类光敏剂,进一步提高氧化钛薄膜的光催化性能,使得光谱响应区红移,在可见光区能够吸收,使太阳能转化成电能成为可能。     

Photocatalytic Active Titania Thin Films through Oxidation of Metallic Ti in Aqueous H2O2 Solutions Containing Various Block Copolymers

利用添加了嵌段共聚物P123、F127及硝酸的双氧水溶液直接氧化钛金属基体制备不同纳米形貌TiO2光催化薄膜。采用X射线衍射(XRD)、扫描电镜(SEM)、紫外-可见漫反射光谱(UV-VisDRS)等技术分析样品的微观结构和形貌,以光催化降解若丹明B测定薄膜的光催化性能。结果表明,Ti-H2O2反应体系中仅添加嵌段共聚物的薄膜结晶呈树枝状,加入硝酸后薄膜形成纳米花结构。450oC热处理后,薄膜为锐钛矿与金红石的混晶结构,平均晶粒尺寸在12～20nm之间。薄膜的间接禁带宽度为2.65～2.85eV,显著低于TiO2块体。添加P123获得的薄膜的光催化性能优于添加F127的薄膜。     

Ti-H2O2反应添加嵌段共聚物制备光催化活性的TiO2薄膜

利用添加了嵌段共聚物P123、F127及硝酸的双氧水溶液直接氧化钛金属基体制备不同纳米形貌TiO2光催化薄膜.采用X射线衍射(XRD)、扫描电镜(SEM)、紫外-可见漫反射光谱(UV-Vis DRS)等技术分析样品的微观结构和形貌,以光催化降解若丹明B测定薄膜的光催化性能.结果表明,Ti-H2O2反应体系中仅添加嵌段共聚物的薄膜结晶呈树枝状,加入硝酸后薄膜形成纳米花结构.450℃C热处理后,薄膜为锐钛矿与金红石的混晶结构,平均晶粒尺寸在12～20 nm之间.薄膜的间接禁带宽度为2.65～2.85 eV,显著低于TiO2块体.添加P123获得的薄膜的光催化性能优于添加F127的薄膜.     

ZnO／Ag纳米复合材料光催化性能研究

通过XRD、TEM测试研究了自制ZnO／Ag纳米复合材料的结构和形貌，通过UV检测确定了以该纳米复合材料为光催化剂，在不同条件下对甲基橙的光催化降解率。结果表明：与空气煅烧相比，真空煅烧所得纳米复合材料的光催化降解效果更好，且光催化降解率随纳米复合材料用量增加而增大：甲基橙溶液的pH在5左右时，光催化降解率最高：H2O2浓度为0．9g／L时，光催化降解率可达100％。     

聚酰亚胺基光催化材料研究进展

聚酰亚胺是一种已经在各种领域被广泛应用的高分子聚合物,而作为可见光响应的光催化材料在光催化领域最近取得了新的关注和研究。由于聚酰亚胺有多种合成手段和原料前驱体,其具有可调电子能带结构和高物理化学稳定性。调研和研究了聚酰亚胺和聚酰亚胺基复合光催化领域的最新研究进展和后续发展思路,重点调研了聚酰亚胺的光催化特性来源：类石墨相氮化碳的微观结构;聚酰亚胺光催化微观结构和性能之间的关系;聚酰亚胺与另外一种能级匹配良好的半导体结合,形成纳米异质结。还从理论上讨论了聚酰亚胺基光催化材料的能带结构、电子性质、光学吸收和界面电荷转移,为电荷载流子动力学提供有洞察力的展望。为促进下一代聚酰亚胺基光催化材料的研究开辟一条新的途径,利用其优异的结构、电子和光学性能可调性,实现进一步的发展,从而实现更高性能的可见光光催化材料的性能。     

TiO2／PSS自组装薄膜的光催化性能

利用静电自组装工艺在石英衬底上制备了结构有序的TiO2／PSS纳米复合膜，并采用UV-Vis-NIR分光光度计、原子力显微镜(AFM)对复合膜的结构与光催化性能进行了深入的研究。结果表明：有序多孔TiO2颗粒膜具有良好的光催化性能，能够在短时间内降解掉复合膜中有机成分，烧结处理薄膜的光催化性能明显优于紫外照射处理的样品。     

NiMoO_4纳米颗粒的溶胶-凝胶法合成及其组织、形貌、光学、磁学和光催化性能（英文）

采用溶胶-凝胶法合成钼酸镍(NiMoO_4)纳米颗粒。以水作为溶剂使所得产品具有纳米晶结构。使用X射线衍射、能量分散X射线分析(EDX)和傅里叶转换红外光谱等手段对纳米晶进行结构表征。使用扫描电镜和透射电镜对纳米晶颗粒的尺寸大小和形貌进行观察。结果表明,所得纳米颗粒和纯度较高,为单相单斜结构。采用紫外-可见漫反射光谱(UV-Vis-DRS)和光致发光测量法研究室温下产品的光学性能。采用振动样品磁强计(VSM)研究样品的磁性能。结果显示,所得样品具有超顺磁行为。考察了NiMnO_4样品的光催化活性。结果显示,添加TiO_2能提高NiMnO_4的光催化活性。测定了催化剂NiMnO_4、TiO_2和NiMoO_4-TiO_2纳米颗粒对4-氯酚(4-CP)的光催化降解行为。光催化降解结果显示,NiMoO_4-TiO_2纳米颗粒的光催化降解效率高于NiMnO_4和TiO_2的。     

新型介孔碳-氧化钛纳米复合材料的制备及协同效应

以介孔氧化钛MTiO2为钛源,葡萄糖为碳源,在500℃的N2保护下合成新型介孔碳-氧化钛纳米复合材料(CMT)。采用X射线衍射、热重和低温N2物理吸附方法对CMT的结构进行表征,同时以甲基橙为目标污染物评价CMT的吸附性能和光催化降解性能。结果表明:随着碳含量的增加,CMT的吸附性增强,但过量的碳会使CMT的光催化性能下降。当碳含量为2%时,纳米复合材料(003CMT)呈现高结晶度的锐钛晶型,生成的碳分散在MTiO2内、外壁面,比表面积为69.8m2/g,孔容为0.22cm3/g,孔径为9.69nm;紫外光催化降解能力超过原有的MTiO2的,说明通过调整碳含量可以让CMT发挥碳的吸附和介孔TiO2光催化的协同效应,提高其光催化性能。     

冷喷涂沉积纳米结构涂层研究进展

纳米结构涂层因具有良好的耐磨性、耐高温、光催化活性及仿生性能等性能,在材料表面改性方面具有重要的应用价值。冷喷涂作为一种低温沉积技术可避免晶粒粗化,保持纳米结构涂层的特性。概述了冷喷涂的工作原理及沉积机理,介绍了影响冷喷涂沉积纳米结构涂层的主要工艺参数和冷喷涂辅助技术;分别从热障涂层、耐磨涂层、光催化涂层、仿生涂层方面阐述了冷喷涂沉积纳米结构涂层的研究进展。并对冷喷涂纳米结构涂层的发展前景进行了展望。     

钛上阳极氧化生成TiO2光催化薄膜的结构与性能

研究了电化学阳极氧化在钛上制备的纳米晶多孔TiO2光催化薄膜的结构与光催化特性。将工业纯钛片或钛箔暴露于电介质溶液并加一定电压，钛表面将氧化生长多孔TiO2薄膜。适当控制氧化电压、溶液温度，得到非晶氧化膜，再进行晶化处理，得到锐钛矿相纳米晶TiO2薄膜。其晶粒尺寸约在10nm～30nm。用SEM，TEM，XRD表征TiO2薄膜的形貌与相结构。用光谱仪测定了薄膜对入射光的吸收特性，表明电化学氧化制备的纳米晶二氧化钛薄膜对近紫外入射光产生强烈的吸收，显示纳米结构的量子效应。测定了薄膜对酸性红溶液的光催化降解效率，结果表明反应30min后薄膜对酸性红的光催化降解率可达95％以上。     

ZnO and TiO2 1D nanostructures for photocatalytic applications

ZnO and TiO₂ 1D nanostructures (nanorods and nanotubes) were prepared by low-cost, low-temperature, solution-based methods and their properties and photocatalytic performance were studied. ZnO nanorod samples with titania and alumina shells were also prepared by solution-based methods, and their properties and photocatalytic performance were compared to that of bare ZnO nanorods. We found that ZnO and TiO₂ exhibited comparable photocatalytic performance. Faster dye degradation under simulated solar illumination was observed for ZnO, while under UV illumination faster degradation was observed for TiO₂. ZnO nanorods with titania shells exhibited inferior photocatalytic performance, while for alumina shells the performance was similar to bare ZnO. Reasons for observed differences are discussed, and the effect of the shell on photocatalytic activity is attributed to the changes in native defects at the ZnO surface/shell interface.     

粒子型TiO_2溶胶和薄膜的制备与性能

利用纳米TiO2粉体制备粒子型TiO2纳米溶胶,并采用浸渍提拉法在普通玻璃表面制备TiO2纳米薄膜。研究粒子型溶胶的胶体特性以及薄膜的表观形貌、透光性、亲水性和光催化性能。结果表明:粒子型TiO2纳米溶胶的常温晶相为锐钛矿相,500℃以后逐步向金红石相转变;TiO2纳米薄膜具有良好的可见光透过性,强的紫外吸收能力,从而具有很好的紫外光光催化性能,同时还具有一定的可见光响应和亲水性能。     

Modification of Parylene film-coated glass with TiO2 nanoparticles and its photocatalytic properties

A titania film was deposited on Parylene-coated glass by a one-step, ultrasound-assisted procedure. The TiO₂ nanoparticles formed during the sonochemical hydrolysis of Ti(i-OPr)₄ were thrown to the surface and strongly attached to the Parylene substrate. By using different solvents (water, ethanol or their mixture) and reagent concentrations, the thickness, uniformity and crystallinity of the deposited layer were regulated. PVP was used to stabilize the highly homogeneous distribution of TiO₂ nanocrystals on the Parylene surface. The morphology and structure of the coated films were characterized by physical and chemical methods such as: X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM), Rutherford backscattering spectrometry (RBS), and optical spectroscopy. The photocatalytic activity of the titania-modified Parylene film in the photo discoloration of methylene blue was demonstrated. The experimental results revealed a correlation between the uniformity of the nanostructured anatase titania film and its photocatalytic properties.     

复合溶胶电泳制备TiO_2涂层的研究

研究了由TiO_2颗粒和TiO_2溶胶组成的复合TiO_2溶胶,以及其电泳制备涂层的光催化性.实验发现复合溶胶的Zeta电位小于相应的溶胶Zeta电位.对于溶胶在不同温度下煅烧制备的TiO_2粉末进行XRD表征,结果表明随着煅烧温度升高,粉末结晶程度提高,从200 ℃开始出现锐钛矿TiO_2晶相,在550 ℃出现金红石型TiO_2.光催化性能表明,由溶胶而得到的TiO_2涂层的光催化性能要好于复合TiO_2溶胶的光催化性能.     

氧化铋/二氧化钛复合颗粒的制备及其光催化降解4-氯苯酚的性能

在低温条件下制备在太阳光照射下具有高光催化活性的氧化铋/二氧化钛复合颗粒。并利用XRD、SEM、BET、XPS和DRS对其进行表征。结果表明：将二氧化钛纳米颗粒沉积在氧化铋表面可形成微-纳结构,使该复合材料表现出多孔性,并提高表面羟基的含量。因此,在太阳光的激发下,氧化铋/二氧化钛复合颗粒对4-氯苯酚的催化降解能力高于纯二氧化钛和P25。     

溶胶-凝胶法制备纳米TiO2及其光催化活性研究

采用正交设计方法，试验研究了4种因素对溶胶-凝胶法制备纳米TiO2光催化活性的影响，确定了各因素所对应的最佳水平，得到了溶胶-凝胶法制备高光催化活性纳米TiO2的最佳工艺条件；且对最佳工艺条件制备的TiO2和商业粉P-25进行了XRD和UV-Vis吸收光谱分析。结果表明，自制的TiO2由纯锐钛矿组成，其平均晶粒尺寸为18．2nm，比混晶型的P-25TiO2晶粒尺寸（24．7nm）要小。自制TiO2粉在330～370nm的紫外光区的吸收增强，在可见光区的吸收也较P-25有所增强。两者都有利于光催化活性的提高，使得光催化降解甲基橙的活性与P-25相当。     

Deposition, Characterization, and Enhanced Adherence of Escherichia coli Bacteria on Flame-Sprayed Photocatalytic Titania-Hydroxyapatite Coatings

Nanostructured titania has been extensively investigated as photocatalytic material and is capable of killing bacteria attached on its surface. The persistent challenge yet is how to effectively promote adhesion of bacteria on its surface for consequent extermination. The study presented here deals with liquid flame-sprayed nanostructured titania-hydroxyapatite (HA) coatings. Addition of HA alleviated phase transformation of titania from anatase to rutile during the coating deposition, reducing rutile to anatase ratio from 9.58 to 1.99%, and precluded effectively aggregation of the nano titania particles in the as-sprayed coatings. Adherence of Escherichia coli bacteria on the coatings showed significant dependence on content of HA, and the increased HA content resulted in enhanced attachment of the bacteria. Examination of the photocatalytic activity of the coatings through decomposition of methylene blue dye in water revealed that addition of HA did not markedly deteriorate the photocatalytic performances of the coatings. The coatings consisting of 10 wt.% HA showed the best photocatalytic activity, which is comparable to that exhibited by immobilized Degussa P25 coatings. The unambiguous evidence provided in this study suggests that the coatings made from combination of biocompatible HA and photocatalytic nano titania have great potential for antibacterium applications.     

Regularity control of porous anodic alumina and photodegradation activity of highly ordered titania nanostructures

A two-step anodizing process was used to prepare wide-range highly ordered porous anodic alumina membrane （PAA） in the electrolyte of oxalic acid. The effects of anodic voltage, anodizing time, size of aluminium foil and additives on the regularity of PAA membrane were also studied in the process of two-step anodization. The template method was combined with the sol-electrophoresis deposition and sol-gel method respectively to prepare highly ordered titania nanostructures. The diameter and length of the obtained nanostructures were determined by the pore size and depth of the PAA template. Scanning electron microscopy （SEM） and X-ray diffraction （XRD） were, used to characterize the morphology and phase structure of the PAA template and the titania nanostructures. The results show that the anodizing time and the additive of ethanol have a great effect on the regularity of PAA template. This can be explained from the self-organized process and the current density theory. A theoretical model based on the self-organized process was established to discuss the formation mechanism of PAA template from the chemical perspective. The titania nanostructures prepared with this method has a high specific surface area. Furthermore, the photocatalytic activity of titania nanostructures on methyl orange were studied. Compared with ordinary titania membranes, the titania nanostructures synthesized with this method have higher photodegradation activity.