气相苯在TiO2光催化剂上吸附常数和光催化反应常数测定

采用溶胶-凝胶法制备TiO2光催化剂以及掺杂Fe3 和Ce3 的TiO2光催化剂,进行间歇式光催化降解气相苯动力学实验,基于光催化Langmuir-Hinshelwood反应动力学模型(L-H模型),测定气相苯在3种光催化剂上的降解动力学常数和吸附平衡常数.根据光催化降解气相苯实验动力学曲线和L-H模型,估算出TiO2、Fe3 /TiO2和Ce3 /TiO2光催化剂光催化降解苯的反应速率常数k和Langmuir吸附常数K分别为0.5247g/m3·min、1.523g/m3·min、1.010g/m3·min和8.605×10-2m3/g、2.390×10-2m3/g、3.928×10-2m3/g.掺杂Fe3 和Ce3 可明显提高光催化剂光催化降解苯的反应速率常数k,其中Fe3 /TiO2,的反应速率常数k最大.     

染料在纳米TiO2薄膜表面吸附性能的研究

采用溶胶－凝胶法制备纳米TiO2薄膜，并通过吸附染料形成染料／TiO2复合薄膜。分析了染料与TiO2薄膜的相互关系，利用紫外可见、比表面等技术研究染料在纳米TiO2薄膜表面的吸附性能，并计算出TiO2薄膜对染料的最大吸附率。研究表明，染料溶液浓度、温度以及TiO2薄膜浸泡时间对染料吸附量有着显著的影响，染料的吸附性能直接影响着太阳能电池的光电转换效率。     

介孔TiO2对溶菌酶吸附的动力学和热力学

773.15 K下焙烧二钛酸(H₂Ti₂0₅)制备了介孔结构TiO₂。采用比表面分析仪(BET)、扫描电镜(SEM)、拉曼(Raman)光谱和X射线衍射(XRD)仪进行表征研究了介孔TiO₂对溶菌酶的吸附行为和机理。结果表明,该吸附过程较好地满足Langmuir吸附模型;随着溶液pH值的增高,溶菌酶在介孔TiO₂上的吸附量先增大后减小。在pH = 7.2时,达到最大吸附容量72.5 mg·g^-1。该介孔TiO₂对溶菌酶具有良好的吸附稳定性,经过5次循环后吸附的溶菌酶残余量仍有81.6%。动力学研究表明,介孔TiO₂与溶菌酶间的吸附满足准二级动力学模型,吸附传质过程由膜扩散和粒内扩散共同影响与控制。对热力学参数的计算发现,该过程ΔG⁰ < 0, ΔH⁰ > 0, ΔS⁰ > 0,表明介孔TiO₂对溶菌酶的吸附是一个自发的、吸热的熵增过程。     

钒离子掺杂对TiO2光催化剂薄膜催化活性的影响

采用溶胶凝胶工艺在普通玻璃表面制备了钒离子非均匀掺杂的TiO2薄膜,运用XRD研究了其光催化复合薄膜的表面特征.以光催化降解甲基橙溶液为模型反应,表征薄膜的光催化活性,结果表明,将钒离子富集在TiO2薄膜内部时,最佳掺杂浓度为1.0%(V/Ti原子百分比),最佳降解表观速率常数为7.44×10-3min-1,约是纯TiO2的2.3倍,有效地提高了TiO2半导体的光催化效率.通过XPS与电化学方法进行分析,说明将钒离子富集在TiO2薄膜内部十分有利于电子-空穴的分离,增强了光生电子与空穴的分离效率.     

柔性TiO2纳米管薄膜电极的制备及其光电性能

采用水热合成法制备出TiO₂纳米管,通过XRD、TEM和氮气等温吸附-脱附仪等测试手段对TiO₂纳米管进行了表征.用烧结的TiO₂纳米管和P25粉末混合制成薄膜电极,并研究了薄膜电极的表面形貌、染料吸附量和光电性能.研究表明,加入TiO₂纳米管可以制备出机械稳定的薄膜;掺杂TiO₂纳米管的含量越多,薄膜电极的染料吸附量越大;掺杂5%烧结纳米管粉末的薄膜电极的光电性能最好,其短路电流可达3.25mA,光电转换效率达到1.67%.     

具有多级复合孔TiO2薄膜的合成及吸附DNA的性能

本文以高分子聚合物(F127)为模板, 以强疏水的1,3,5-三甲基苯为有机添加物, 通过旋转覆膜的方法制备出具有多级复合孔的二氧化钛晶体薄膜, 并采用TEM和SEM对样品结构进行了分析, 同时考察了这种薄膜对DNA分子的吸附性能.     

流动注射分析在线研究Cr(Ⅵ)在纳米TiO2表面上的吸附动力学性质

用溶胶-凝聚法在不同的水解和热处理条件下制备了纳米尺寸的TiO₂微粉,所得的TiO₂表面性质迥异,粒径从几个纳米到数百个纳米,晶型也由低温煅烧的锐钛型转成高温处理时的金红石型.利用流动注射微柱富集在线分析方法对Cr(Ⅵ)离子在纳米TiO₂表面上的吸附动力学特性进行了原位表征.     

TiO2光催化薄膜在陶瓷器具上抗菌效果的研究

抗菌薄膜;TiO2光催化薄膜在陶瓷器具上抗菌效果的研究     

β-环糊精在TiO2上的吸附及其对光催化影响研究

用酚酞法测定TiO2悬浮液中β-环糊精(β-CD)的量以及用β-CD溶液平衡的TiO2经过滤、洗涤和干燥后进行漫反射红外光谱和XPS能谱表征．结果表明：β-CD分别在纳米和P25型TiO2表面通过羟基间作用形成化学吸附，吸附量与溶液pH值有关，且最大吸附量在TiO2等电点附近．β-CD可提高两种TiO2对甲基橙光催化脱色速率.提高的效率与溶液pH值有关．实质上，提高的效率与β-CD在TiO2表面吸附量和甲基橙在TiO2表面的静电吸附量有关，即与甲基橙-β-CD—TiO2三元间的相互作用有关。     

A Novel Synthesis of Two-dimensional Nanopatterned TiO2 Thin Film

Recently the research on structures with an ordered two-dimensional(2D) pattern has attracted great attention due to its versatile applications in the fields of microelectronic and optoelectronic devices, displays, biochips and sensors, enzymatic immobilization, drug carriers, and photonic band gap materials. Various well-arrayed 2D structures have been made by the modern technique such as laser writing pattern fabrication, photoetching technique, micro-electromechanical systems based on scann…     

TiO2光致双亲性与水性油墨转印的研究

研究了TiO2薄膜作为一种新型印刷材料的浸润性与光照时间和光照强度的关系以及光照时间对水性油墨在薄膜表面吸附的影响,实现了水性油墨由TiO2薄膜向纸张的多次转移.     

Preparation of the TiO2 Thin Film Photocatalyst by the Dip-Coating Process

Titanium dioxide (TiO2) coated glass-plate thin film photocatalysts for elimination of air pollutants, were prepared by the dip-coating process with titanium alkoxide including polyethylene glycol (PEG). The surface structure of these thin films changed drastically with the size of the PEG. They were either transparent or opaque. Nitrogen oxides (NOx), one of the most hazardous of air pollutants, were found to be efficiently eliminated by the thin film photocatalyst. The photocatalytic activities of the transparent and opaque thin films were found to be almost equal. This may be due to the two films having the same surface area. The highest activity was obtained for thin films around 1 m.     

A Novel Nanocrystalline TiO2 Thin Film Electrodes Prepared at Low Temperature

Nanocrystalline TiO2 thin films were successfully prepared by a new ““water-cooked““ method on both conductive glass substrates and flexible substrates at low temperature. Dye-sensitized solar cells based on these films have exhibited high overall light-to-electricity conversion efficiencies of 4.67 % and 1.94 % on conductive glass substrate and flexible substrate, respectively, under the illumination at 100 mW/cm^2.     

Photostability Study of Nanoporous TiO2 Film Electrodes in Basic Solutions

The nanoporous TiO2 film electrodes have been prepared by a sol-gel deposition process The photostability of the electrodes in basic solutions has been studied. The results show that the photostability of the electrodes decreases rapidly in strong basic solutions with or without methanol. The reaction of holes to O^2- produces active O^2- atoms and the products O^2- atomsoxidize Ti^3 to Ti^4 on TiO2 film surface and subsurface. This results in the TiO2 film electrodes unstable in basic solutions both without methanol and with too low concentration.     

Preparation and Magnetic Properties of Submicron CrO2 Thin Film on Poly-crystal TiO2 Film

The submicron chromium dioxide(CrO₂) thin film was fabricated on a poly-crystal titania(TiO₂) film using Si wafers as substrates by atmospheric pressure chemical vapor deposition(CVD) method. X-Ray diffraction patterns show that the CrO₂ films were pure rutile structure. Scanning electron microscopy(SEM) images indicate that the CrO₂ films consisted of submicron grains with a grain size of 250―750 nm. The magnetic researches reveal that the magnetic easy axis is parallel to the films, and at room temperature, the CrO₂ films show linear magnetoresistance.     

不同波长紫外光照下纳米TiO2薄膜的光致亲水性与循环伏安行为

通过溶胶-凝胶方法分别在ITO和玻璃表面制备了纳米TiO_2薄膜，研究了纳米 TiO_2薄膜在254及365nm的紫外光照射下的循环伏安行为和光致超亲水性。在紫外 光的照射下，TiO_2薄膜电极可表现出两个光电化学过程，纳米TiO_2薄膜的光致超 亲水性转变及两个光电化学过程的速率均取决于紫外光的波长，原因在于纳米 TiO_2薄膜对两种波长的光的吸收率和光子的能量不同。提出了光电化学过程的机 理，认为紫外光照射下纳米TiO_2薄膜的超亲水性变化与产生Ti~(3+)的过程引起的 表面微观结构变化存在的一定的内在联系。     

Platium Film Electrodes (1) Platium Film on Ti or TiO2-Covered Ti

A platium film was formed on a Ti(Pt-Ti) and on a TiO₂(Pt-TiO₂-Ti) substrate by the conventional electroplating method (ELP) and by the electroless plating technique (ELSP). The effective minimum film thickness was found to be 0.5 μm judging from the maximum electrocatalytic capablity in alkaline (1 M NaOH) water electrolysis. The film obtained from ELP is superior to that obtained from ELSP, being more tightly bound to the substrate, showing better coverage of the subsrate surface, and also being mechanically stronger. Comparisons with bright Pt and with Pt-black electrodes were made and it is concluded that the electrodes newly prepared using ELP will work as well as Pt-black electrods. The electrodes from ELSP are useful only as cathodes, and are not suitable as anodes.     

液相沉积法制备光催化活性TiO2膜

锐钛矿型TiO2薄膜;液相沉积法制备光催化活性TiO2膜     

Electronic Structure Effect of Polythiophene Derivatives and Nano N-Zn-Ag/TiO2 on Performance of Organic Thin Film Solar Cell

Nanocrystal N-Zn-Ag/TiO₂ powders were prepared with N-Zn/TiO₂ by photo deposition method. A series of pure polymers P3HT[poly(3-hexylthiophene)], P3OT[poly(3-octylthiophene)], P3DT[poly(3-decylthiophene)] and P3DDT[poly(3-dodecylthiophene)], was synthesized, which were used to synthesize p-n type semiconductor materials P3HT/N-Zn-Ag-TiO₂, P3OT/N-Zn-Ag-TiO₂, P3DT/N-Zn-Ag-TiO₂ and P3DDT/N-Zn-Ag-TiO₂ by in situ che-mical method. X-Ray diffraction(XRD) and infrared(IR) spectroscopy showed the structure of the polymers and complexes. Ultraviolet-visible(UV-Vis) spectra and cyclic voltammograms(CV) showed the optical and electronic performance of the polymers and complexes. Two new single and double organic thin film heterojunction solar cells were prepared with the above mentioned synthesized powders as raw materials. Current-voltage(I-V) measurements indicate that the conversion efficiency of the single organic thin film heterojunction solar cell is higher than that of the double organic thin film heterojunction solar cells. Single organic thin film heterojunction solar cells based on P3DT/N-Zn-Ag-TiO₂ can get a photoelectric conversion efficiency of 0.0408%. The performance of electronic transform between electron donor and acceptor on organic thin film solar cells was researched.