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1.
纳米晶TiO2的合成及表面态研究   总被引:1,自引:0,他引:1  
采用硬脂酸凝胶法制备了TiO2纳米材料,用差热-热重分析、红外光谱分析、X光衍射分析、透射电镜、表面光电压谱和X光光电子能谱等手段对TiO2制备过程及产物的晶型、形貌、表面光电特性等进行了分析。实验结果表明,TiO2纳米材料的表面结构有利于光催化活性的提高。  相似文献   

2.
纳米TiO2的制备,表征及光催化性能的研究   总被引:41,自引:2,他引:39  
采用硬脂酸凝胶(SAG)法制备了TiO2纳米材料,用差热分析,热重分析,X射线衍射对合成过程进行了研究。用X射线光电子能谱(XPS)对其表面状态进行了分行。TiO2纳米材料对甲基橙溶液光催化降解结果表明:催化剂浓度、初始溶液pH值和金属离子对降解效率有较大影响。  相似文献   

3.
本文在长有ZnO纳米粒子作为"种子层"的FTO基底上用水热合成法制备了取向高度一致的ZnO纳米线阵列,用TiCl4的异丙醇溶液在ZnO纳米线阵列的表面生长了纳米结构的TiO2。利用扫描电子显微镜、能量散射谱、X射线衍射分别表征纳米材料的形貌和结构,用Raman光谱研究了材料的晶格结构特性。染料敏化太阳电池的性能测试表明,与纯ZnO作为光阳极相比,ZnO/TiO2复合纳米材料作为光阳极的器件,开路电压和填充因子都得到了提高。  相似文献   

4.
通过控制四氯化钛(TiCl4)的水解速度,制备出水杨酸(SA)原位表面修饰的TiO2纳米颗粒(TiO2/SA).通过X射线衍射仪(XRD),高分辨透射电子显微镜(HRTEM),红外光谱仪(FT-IR),热分析(TG-DTA)和X射线光电子能谱(XPS)等实验分析手段对表面改性前后的TiO2纳米颗粒进行了表征,结果表明表面修饰水杨酸的TiO2纳米颗粒在乙醇中有良好的分散性,将TiO2/SA加入到光信息存储薄膜材料(PVA/AM)中,能大大提高材料的衍射效率,降低布拉格偏移.  相似文献   

5.
利用一种模板辅助的两步法制备了一系列Zn2+掺杂的TiO2中空纤维纳米材料(Zn2+/TiO2);利用扫描电子显微镜(SEM)、X射线衍射(XRD)、X光电子能谱(XPS)和紫外-可见光谱(UV-Vis)等技术进行表征;以亚甲基蓝(MB)的降解为模型反应,考察Zn2+量对TiO2中空纤维纳米材料光催化性能的影响。结果表明:制备的样品为复制了模板形貌的中空结构纳米纤维材料;在0.00~0.62%Zn2+量范围内,Zn2+/TiO2的光催化活性明显高于TiO2的,且随掺杂量呈先增后降的变化趋势,当Zn2+量在0.29%左右时,其光催化活性最高,在太阳光下3h,MB溶液在Zn2+/TiO2表面的脱色降解率达98%以上,而在TiO2表面仅为60%;Zn2+/TiO2在重复使用5次时仍能保持MB溶液脱色率在90%以上。样品Zn2+/TiO2所表现出的优良催化性能是众多因素-表面羟基、吸附氧、Zn2+活性位、特殊的纤维形貌等协同作用的结果。  相似文献   

6.
纳米TiO2稀土元素掺杂改性与光催化性能研究   总被引:13,自引:1,他引:13  
采用溶胶-凝胶法制备纳米材料,以钛酸丁酯为前驱体,冰醋酸为螯合剂,通过水解缩聚作用制备纳米TiO2,掺杂稀土元素Ce对纳米TiO2进行改性,运用热分析(DSC)、X射线衍射(XRD)、透射电镜(TEM)和光吸收等手段,研究了不同掺杂量对TiO2相变和光催化活性的影响,确定了最佳的掺杂量和热处理温度。  相似文献   

7.
纳米TiO2/Sb2O5涂层的光生阴极保护研究   总被引:1,自引:0,他引:1  
采用溶胶凝胶法在304不锈钢表面制备了纳米TiO2/Sb2O5叠层涂层. 用扫描电子显微镜(SEM)、X射线衍射(XRD)、X射线光电子能谱(XPS)对涂层表面形貌、晶体结构以及组成进行表征. 采用电化学方法研究涂层的光电化学性能与光生阴极保护特性. 结果表明,所制备的纳米TiO2/Sb2O5叠层涂层表面连续、均匀、致密;XRD分析表明纳米TiO2为锐钛矿型;XPS分析表明纳米涂层表面与内层均由Ti、Sb、O、C四种元素组成;稳定电位与极化曲线测试表明,在3%NaCl溶液中,纳米TiO2/Sb2O5叠层涂层的光电化学性能低于纯纳米TiO2涂层,但纳米TiO2/Sb2O5涂层经紫外光照1h,停止紫外光照后的延时阴极保护作用可达4h. 通过研究分析,提出了一种新的纳米叠层涂层光生阴极保护作用机理.  相似文献   

8.
以硅烷偶联剂作为表面修饰剂,在大气气氛中于普通载玻片上的有机单层上选择沉积制备出TiO2薄膜.使用差示扫描量热-失重(DSC-TG)分析、X射线衍射(XRD)分别对TiO2薄膜的凝胶前驱体和TiO2粉末进行表征,并对TiO2薄膜进行了X射线荧光光谱(XRF)分析.结果表明,所制备的TiO2薄膜是纳米级的锐钛矿单层膜.  相似文献   

9.
为了提高TiO2/Ti光电极在可见光下的光电催化活性,采用阳极氧化法制备了一种新型的硫掺杂TiO2/Ti光电极.采用扫描电子显微镜、X射线衍射、X射线荧光光谱等技术对光电极进行了表面形貌、结晶形态、晶粒尺寸、硫的掺杂量和价态以及吸光性能表征.研究表明:硫掺杂TiO2/Ti光电极的最佳制备条件为:成膜电压160V、电流密度100mA/cm2、Na2SO3质量浓度750mg/L;所制备的光电极具有良好的光电催化氧化降解邻苯二甲酸二甲酯活性,并能有效地矿化其中间产物;与TiO2/Ti电极相比,硫的掺杂可以显著提高其在可见光下的光电催化性能.  相似文献   

10.
纳米填料与塑料共混,可以改善塑料的强度、韧性.但是纳米填料与塑料的相容性差,需要对纳米材料进行表面改性.采用硅烷偶联剂γ-(甲基丙烯酰氧基)丙基三甲氧基硅烷对纳米Ti02进行表面处理,在其表面引入双键,然后与苯乙烯共聚,制备表面接枝聚苯乙烯的纳米TiO2粒子,拟用于聚苯乙烯抗冲击改性.采用红外光谱、扫描电镜、原子力显微镜对接枝聚合后的纳米TiO2粒子的形貌进行观察,并且采用热失重分析法定量表征纳米材料表面的接枝率.结果表明:通过悬浮聚合,TiO2粒子表面成功接枝聚合了聚苯乙烯.  相似文献   

11.
纳米TiO2粉晶的XRD研究   总被引:36,自引:5,他引:31  
尹荔松  周歧发 《功能材料》1999,30(5):498-499,511
用溶胶-凝胶法制备了纳米TiO2粉晶,对不同温度自理的系列粉末用X射线衍射进行了研究,发现所得粉晶随热处理温度的不同发生了从锐钛矿到金红石相的转变。对系列粉晶进行了X射线衍射点阵参量计算,结合所得的晶粒度和微结构参数,发现纳米TiO2粉晶组元中存在着晶格畸变。  相似文献   

12.
304不锈钢纳米TiO_2涂层的结构形貌与防腐蚀性能   总被引:1,自引:0,他引:1  
纳米TiO2涂层对304不锈钢具有较好的防腐蚀性能.采用溶胶-凝胶法与浸渍提拉技术在304不锈钢上制备纳米TiO涂层,用扫描电子显微镜(SEM)、X射线衍射(XRD)和X射线光电子能谱(XPS)对涂层的结构、形貌及组成进行了表征,采用电化学方法研究了涂层的防腐蚀性能,并对其光阴极保护机理进行了探讨.结果表明:所制备的纳米TiO2涂层外观呈蓝色,表面连续、均匀,颗粒呈球形;TiO2为锐钛矿型;涂层主要由Ti,O和C 3种元素组成;纳米TiO2涂层具有一定的光电化学效应和防腐蚀性能.  相似文献   

13.
采用化学共沉法和TiCl4水解法制备CoFe2O4磁粒子和核壳型CoFe2O4/TiO2光催化剂,在100℃烘干,350℃焙烧2 h,在紫外光源和太阳光照射下所制备的CoFe2O4/TiO2光催化剂显示出较高的甲基橙降解能力,利用外加磁场很容易将CoFe2O4/TiO2光催化剂和所处理的污水分离,并可循环使用.TEM和XRD分析结果表明:CoFe2O4粒径约为20nm,TiO2包覆的CoFe2O4粒子的粒径约为30~40nm,TiO2包覆层约为10~20nm.  相似文献   

14.
用x-ray衍射分析,差热分析及扫描电镜等方法,探讨了氧化钛添加量对基础玻璃的晶化速率,晶相组成与微观结构以及微晶下班部分性能的影响。结果表明:添加适量的氧化钛将形成中间相,通过中间相诱导析晶,可降低基础上化温度,提高晶化速率。在所研究的CaO-Al2O3-SiO2系统中,氧化钛的最佳添加量的10wt%。  相似文献   

15.
用X射线光电子能谱(XPS)和小掠射角X射线衍射(GAXRD)研究了铝合金LY12等离子体基离子注入形成AIN/TiN改性层的成分分布及相结构.在此基础上测量了改性层的纳米硬度,并进行了摩擦磨损试验.结果表明,氮和钛都能有效地注入到铝合金里,后注入的元素对先注元素的含量和分布有重要影响.钛、氮同时注入在试样表面形成一层稳定的钛、氮化合层.和未改性试样相比,所形成的AIN/TiN改性层纳米硬度及承载能力都提高5倍以上.在低滑动载荷下,摩擦系数减小70%以上,耐磨性提高近10倍,耐磨寿命提高了近6倍,粘着磨损程度显著减轻.随着载荷的增加,相应的耐磨性能有所降低.适当的改性层结构及其中分布的TiO2、TiN、TiAl3、Al2O3、AIN等相是性能改善的主要原因.,The disfribution of composition and microstructure of the AIN/TiN layer of aluminum alloy 2024 im-planted by Plasma Based Ion Implantation(PBⅡ) were characterized using X -ray Photoelectron Spectroscopy(XPS) and Glancing Angle X -ray Diffraction (GAXRD). XPS results show that N and Ti can be implantedinto 2024 effectively, the content of N presents a Gaussian - like distribution, and that of Ti decreases gradu-ally along the implanted direction from the surface. The post -implanted elements have great influence on thecontent and depth profile of the pre - implanted ones. The simultaneously implanted Ti and N can form asteady layer of Ti and N on the surface. In comparison with 2024, the AIN/TiN layer has remarkably improvedthe mechanical properties, of which both the nano - hardness and the load bearing capacity have in most cases increased over 5 times, the friction coefficient has been decreased more than 70% , wear life has been im-proved near to 6 times, and the wear resistance has enhanced approximately 10 times and the degree of adhe-sive wear has lightened markedly at low sliding loads. Nevertheless, the wear-resistant properties are reducedgradually with increasing the sliding load. The great improvement of the mechanical properties is mainly owingto the proper structure of the layer and the presence of TiO2, TiN, TiAl3, Al2O3, and AIN phases in it.  相似文献   

16.
Three different Ti-Si oxide structuares, silica supported titania, silica coated titania and intimately mixed silicatitania, containing 10%-40% SiO2, were made by sol-gel process. The variations of microstructure parameters of nanocrystalline (nc) TiO2-anatase in the three kirds of binary oxides, including in-plane spacing d, cell constants (ao, co), cell volume V, cell axial ratio co/ao and crystal grain size, were comparatively investigated by high resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD). It is found that the microstructure parameters vary remarkably with increasing SiO2 content and annealing temperature. Different structured Ti-Si binary oxides lead to different variation tendencies of microstructure parameters. The more SiO2 the binary oxide contains, the more lattice defects of nc TiO2-anatase appear; diffusion or migration of Si cations could be an important influential factor in the variations of microstructure. The grain size of nc TiO2 in the three kinds of binary oxides not only depends on SiO2 content and annealing temperature but also on the degree of lattice microstrain and distortion of nc TiO2-anatase. Both grain size and phase transformation of nc TiO2-anatase are effectively inhibited with increasing SiO2 content.  相似文献   

17.
The paper demonstrates that the photocatalytic activity of TiO2 towards the decomposition of gaseous benzene in a batch reactor can be greatly improved by loading TiO2 on the surface of CeO(2)-ZrO(2). The research investigates the effects of three metals doping into Ce(0.5)Zr(0.5)O(2) on photocatalytic activity of TiO2/Ce(0.45)Zr(0.45)M(0.1)O(X) (M=Y, La, Mn). The prepared photocatalysts were characterized by BET, XRD, UV-vis diffuse reflectance and XPS analyses. BET surface area of TiO2/Ce(0.45)Zr(0.45)M(0.1)O(X) (M=Y, La, Mn) is smaller than that of Ce(0.5)Zr(0.5)O(2). XRD results reveal that the deposited titania is highly dispersed as in the CeO(2)-ZrO(2) matrix, doping M in the CeO(2)-ZrO(2) lattice causes the changing of lattice space and the diffraction peaks shift to higher 2theta position. Among these four catalysts, the band gap value of TiO(2)/Ce(0.45)Zr(0.45)La(0.1)O(X) is the lowest. The binding energy value of Ti 2p(3/2) of four catalysts transfers to a lower value. The order of photocatalytic activity is TiO2/Ce(0.45)Zr(0.45)La(0.1)O(X)>TiO2/Ce(0.45)Zr(0.45)Y(0.1)O(X)>TiO2/Ce(0.45)Zr(0.45)Mn(0.1)O(X)>TiO2/Ce(0.5)Zr(0.5)O(2)>TiO2. The proposed mechanism is of electron transfer and the stronger absorption in the region 210-400 nm.  相似文献   

18.
利用溶剂热合成法成功制备出了形貌为准球形、棒形、球棒混合型和菱形,粒径在50nm以下、尺寸均一的锐钛矿型TiO2纳米晶,对合成出的纳米晶TiO2用荧光光谱,紫外/可见光吸收光谱进行光学性能表征,结果表明,TiO2纳米晶在330 nm的激发光下,分别在345 nm、363nm、380nm和402 nm处存在4个发光峰位。在实验中,首次发现和证实了理论计算出的锐钛矿型TiO2纳米晶的两种直接跃迁发光,分别对应为X(1b)→X(2b)(345 nm)和X(1b)→X(1a)(363 nm),主要因为油酸改变了TiO2纳米晶的{001}晶面族晶面的表面态。TiO2纳米晶的紫外吸收峰位于229 nm,且与其形貌无关;禁带宽度的计算值接近其理论值3.2 eV。  相似文献   

19.
TiOSO4热水解法制备超细TiO2粉末光催化剂   总被引:4,自引:0,他引:4  
采用TiOSO4热水解法制备超细TiO2粉末光催化剂,探讨了不同制备条件对光催化性能的影响,采用XRD、TEM、BET、TG-DTG-DTA对催化剂进行表征,初步说明TiO2光催化活性与其晶型、粒径大小、比表面等微结构的关系。实验结果表明,在160℃热处理下制备的TiO2粉末是球形和多孔型结构,比表面积约为170m^2/g,只有锐钛型单一晶相和无定型组成,颗粒平均粒径为20nm,其光催化活性与商业化Degussa P25 TiO2超细粉末相近。  相似文献   

20.
An easy process was developed to synthesize TiO(2) nanowires sensitized with CdS and CdTeS quantum dots (QDs) requiring no pretreatment of the TiO(2) nanowires prior to nanoparticle generation. CdS and CdTeS nanoparticles were firstly grown by an in situ colloidal method directly onto the TiO(2) surface, hence not requiring subsequent functionalization of the QDs. The resulting nanostructure assembly and composition was confirmed by transmission electron microscopy (TEM), x-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Successful decoration of the TiO(2) nanowires by the QDs was observed by TEM, while XPS spectra provided clear evidence for the coexistence of CdS and CdTeS QDs and TiO(2) nanowires. The electronic structure of the TiO(2) nanowires was preserved as indicated by Raman spectroscopy. Preliminary photocurrent measurements showed that inclusion of Te in CdS QDs improved the photocurrent efficiency. Compared to bare TiO(2) nanowires, CdS/TiO(2) nanoassemblies showed an enhancement in photocurrent efficiency of 300% while CdTeS/TiO(2) presented an improvement of 350%. This study indicates that the generation of strongly anchored CdS and CdTeS QDs on a TiO(2) nanowire surface is achievable without introduction of a linker molecule, whose presence is known to decrease the electron injection efficiency.  相似文献   

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