TiO2/Mo-TiO2 的制备、表征和光催化活性

 采用溶胶-凝胶法制备了掺 Mo 的 TiO2 粉末, 再由其制得 TiO2/Mo-TiO2 复合物光催化剂. 使用 X 射线光电子能谱、X 射线衍射、透射电镜、N2 吸附-脱附、紫外-可见漫反射光谱和荧光光谱等手段对催化剂进行了表征. 在紫外光照射下, 以甲基橙溶液降解为探针反应, 研究了 Mo 掺杂量对样品光催化活性的影响. 结果表明, Mo-TiO2 催化剂的活性不如纯 TiO2, 这是因为 Mo 离子促进了光生载流子的复合; 而带有 n-n 异质结半导体结构的 TiO2/Mo-TiO2 复合催化剂具有比纯 TiO2 和 Mo-TiO2 催化剂更高的光催化活性. 当 Mo 掺杂摩尔分数为 2%, TiO2:Mo-TiO2 质量比为 10:1 时, 活性是纯 TiO2 的 1.57 倍.     

溶胶-凝胶法制备TiO2/玻璃膜和光催化降解玫瑰红B的研究

以Ti(OC4H9)4为原料采用溶胶－凝胶法制备了纳米TiO2／玻璃薄膜光催化剂，用X射线衍射法对催化剂的物相、粒径进行了表征。结果表明，薄膜中TiO2为锐钛矿晶型，粒径15－25nm。用X射线光电子能谱法分析膜的化学组成。磨擦学实验表明，TiO2／玻璃膜具有良好的减磨和抗磨性能。水中染料玫瑰红B的光催化氧化降解实验结果表明，TiO2膜对玫瑰红B玫解有很高的催化活性，其降解反应对时间和浓度均为一级反应，反应速率可用Langmuir-Hinshelwood方程描述。     

钛、铝和玻璃上TiO2光催化膜的失活研究

采用浸渍提拉法，在平行条件下制备了钛、铝和玻璃载体上的TiO₂膜TiO₂ / Ti、TiO₂ / Al和TiO₂ / G，利用X射线光电子能谱(XPS)、原子力显微镜(AFM)和光催化降解实验等手段对膜样品进行了表征和活性评价。实验结果表明，在铝和玻璃基材上制膜时发生了显著的基材元素溢出，使各膜样品的化学组成不同，同时TiO₂粒子和膜表面形貌也因前驱物烧结行为不同而差异较大。TiO_{2相似文献}   

纳米粒子TiO2/Ti膜的表征及其光催化活性

以钛酸四丁酯为原料，采用溶胶－凝胶法，在600℃焙烧制备了纳米粒子TiO2/Ti膜，并利用TG－DTA，XRD、SEM、XPS、PL、SPS和EFISPS测试技术，对膜样品进行了表征。结果表明，纳米粒子TiO2/Ti膜表面为高密度的均匀碎片结构，TiO2纳米粒子具有与国际P-25TiO2粒子相类似的组成、结构以及微晶尺寸；在纳米粒子TiO2/Ti膜的表面，Ti主要以＋4价化学态存在。而O主要以晶格氧、羟基氧和吸附氧3种化学态存在。以纳米粒子TiO2／Ti膜的PL光谱测试中，以260nm为激发波长，观察到了峰位在380nm处的PL光谱，该值与SPS信号的响应阈值是一致的，此PL光谱峰可能与导带低的电子向价带顶的能级跃迁有关，同时说明了TiO2纳米粒子的量子尺寸效应的影响要大于库仑作用能和表面极化能的影响。以310nm为激发波长，分别观察到了与锐钛矿和金红石相关的发光信号；以450nm为激发波长，观察到了与表面态相关的弱的发光信号。此外，在光催化降解苯酚实验中，当涂膜3次时，TiO2粒子膜达到最高的光催化活性。     

反应磁控溅射法制备的氮掺杂TiO2光催化膜的氮化学态和光催化活性

 采用中频交流磁控溅射法,以O2/N2混和气为反应气体,在铝片上沉积了氮掺杂TiO2膜. 利用原子力显微镜、紫外-可见光谱、X射线衍射和X射线光电子能谱等手段研究了掺杂膜的表面形貌、光吸收性能、物相组成以及膜样品中氮的化学态,并通过苯甲酰胺的光催化降解实验对光催化剂活性进行了评价. 结果表明,所得掺杂膜仅能够被紫外光所激发,反应气的配比对膜的形貌和TiO2的锐钛矿/金红石相比率均有影响,而氮在膜中以掺杂N3-、表面吸附N2和固溶N2的形式存在. 随着N3-掺入量的增加,掺杂膜的光催化活性显著提高,在反应气体组成为N2/(O2+N2)=80%(体积分数)时,掺杂N3-量为0.594%,苯甲酰胺光催化降解效果最好,其活性约为纯TiO2膜的1.5倍.     

TiO2纳米粒子膜的制备,表面态性质和光催化活性

在酸性和碱性条件下,用ＴｉＣｌ４水解法制备了ＴｉＯ２纳米粒子膜催化剂。采用原子力显微镜（ＡＦＭ）,Ｘ射线衍射（ＸＲＤ）,表面光电压谱（ＳＰＳ）和场诱导表面光电压谱（ＥＦＩＳＰＳ）测定了催化剂表面的微结构及能级结构。     

用于溶胶—凝胶提拉法成膜的拉膜机

用于溶胶－凝胶提拉法成膜的拉膜机赵贵文王成云邵学广苏庆德（中国科学技术大学应用化学系合肥２３００２６）沈连（中国科学技术大学精密机械与精密仪器系合肥２３００２６）早在７０年代，Ｓｃｈｒｏｅｄｅｒ就采用浸渍拉膜法改善玻璃的光学性能［１］。近年来，该技...     

溶胶—凝胶法制备负载型TiO2膜的研究

本研究采用溶胶－凝胶（Ｓｏｌ－Ｇｅｌ）法制备了负载型ＴｉＯ２膜，并采用ＳＥＭ、压汞等实验手段对Ｔｉ（ＯＨ）４溶胶和ＴｉＯ２膜进行了表征。实验表明：Ｔｉ（ＯＨ）４溶胶制备过程中Ｈ２Ｏ／Ｔｉ＾４＋、Ｃ２Ｈ５ＯＨ／Ｔｉ＾４＋的比值，溶胶在支承管上浸涂的时间、次数以及凝胶煅烧升温速度和煅烧温度均是制备负载型ＴｉＯ２膜的重要因素。最终制得一种无裂纹、２０μｍ厚、孔径分布在５０￣３００ｎｍ之间的负载型ＴｉＯ２     

复合光催化剂CeO2/TiO2的制备及性能研究

采用溶胶-凝胶-浸渍法制备了CeO2／TiO2二元复合纳米光催化剂,用XRD、FTIR等对其进行了表征。以紫外灯为光源,直接耐晒兰(DFB)的脱色为模型反应,研究了CeO2／TiO2的光催化活性。结果表明：掺杂摩尔百分比x(CeO2)=1．44％、600℃煅烧2h时,该催化剂的催化活性最高,比纯TiO2高近1倍。DFB脱色的最佳条件为：pH9．0～10．0,投加量200mg／50mL,空气流量200mL／min。     

正钛酸胶溶法制纳米TiO2薄膜及性能表征

The Nanometer TiO₂ thin film was prepared by sol method with titanic acid precursor from industrial TiOSO₄ solution. The characters of the sol and the factors affecting sol formation were investigated by ζ electricity potential. The crystalline structure, particle size, appearance shape and photo-catalytic activity were characterized by XRD, SEM, TEM and spectrophotometer. The study show: (1) pH value and HNO₃concentration effected importantly on the forming process and stability of the sol. The thermodynamic condition for forming sol is pH=0.5～1.5. The lower the HNO₃concentration,the more stable the sol. The ζ electricity potential of the sol, with 5% HNO₃as gluing reagent, was up to 48 mV, and shelf life of the sol could more than 10 months. (2) The film, made from the sol and crystallized at 400 ℃, had the characters of anatase structure and crystal size of 18.5 nm by XRD analysis. The SEM imagines show that TiO₂ film was with the characteristics of tight surface structure, The TEM imagine showed the mean particle size is about 20 nm. The photo-degrading test data indicate that the photo-degrading rate to methyl orange solution of 20 mg·L^-1 was more than 84% in 5 hours.     

金属离子掺杂的TiO2薄膜的制备及其光催化降解甲苯的性能

 采用溶胶-凝胶法制备了负载于铝板上掺杂金属离子的TiO2薄膜光催化剂,并通过空气中甲苯光催化降解实验评价了其光催化活性. 结果表明,Pt和Fe的掺杂对TiO2薄膜的光催化活性起促进作用,甲苯降解率分别提高了17%和6%; Ag的掺杂引起催化剂失活; Mn的掺杂未对TiO2薄膜的光催化活性起明显促进作用. XRD结果表明,掺杂金属离子前后TiO2均为锐钛矿相; TEM观察到薄膜催化剂微观结构为球形颗粒,粒径分布均匀,平均粒径为19 nm; 紫外漫反射光谱表明,Pt-TiO2薄膜催化剂的反射率几乎为0,表明其对光的吸收能力很强,因而Pt掺杂的TiO2薄膜光催化降解甲苯的活性最高.     

玻璃和石英基体上沉积的TiO2薄膜的光催化性能

采用直流磁控反应溅射法,在玻璃和石英基体上制备了TiO2薄膜.在氧气流速超过阈值的条件下溅射,能够得到均匀透明的TiO2薄膜.在玻璃和石英基体上制备的薄膜都由均匀的锐钛矿型氧化钛晶粒组成,在晶粒中间分布着微小的孔隙.尽管在整个光谱区域内石英基体的透射率都比玻璃基体高,但在两种基体上制备的TiO2薄膜的光谱吸收边沿基本相同.薄膜中的Ti都以Ti4 形式存在.两种TiO2薄膜光催化降解甲基橙的能力相差不大.     

Sm掺杂对TiO2薄膜光催化性能的影响

 采用溶胶-凝胶法、浸渍-提拉法制备了不同形式和不同含量Sm掺杂的锐钛矿晶型TiO2的光催化剂薄膜. 采用X射线衍射、UV-Vis光谱及电化学实验对所制得的TiO2光催化剂薄膜进行了表征,并通过甲基橙溶液的光催化降解实验评价了其光催化活性. 结果表明,与未掺杂的TiO2薄膜相比,Sm掺杂的TiO2薄膜的UV-Vis吸收光波长向长波方向移动,并且光照开路电压也相应提高; 适量Sm掺杂可以明显提高TiO2薄膜的光催化活性,最佳Sm掺杂量为x(Sm3+)=0.5%; 在各种掺杂形式中以表层Sm掺杂的Sm-TiO2(S)薄膜的光催化活性最好. 讨论了Sm掺杂提高TiO2薄膜光催化活性的机理.     

Sol-Gel Preparation of Photocatalytic TiO2 Films on Polymer Substrates

Sol-gel TiO₂ thin films were autoclaved under various water/ethanol atmospheres. The microstructural, morphological and photocatalytic properties of the films were studied. The photocatalytic activity of the films appears closely related to crystallization states. It is shown that nanocrystallized porous films can be produced in a temperature range compatible with titania deposition on polymer materials. Consequently, photocatalytic films could successfully be prepared on polycarbonate and polymethylmetacrylate substrates. The autoclaved film properties are described and discussed with respect to sol-gel parameters and autoclaving conditions.     

TiO2薄膜的Ag改性及光催化活性

 用光化学沉积法对纳米TiO2薄膜进行了Ag改性,用漫反射紫外-可见光谱、扫描电子显微镜和X射线光电子能谱分析了Ag-TiO2薄膜的光谱特征、表面形貌和表面组成. 以苯酚为模拟污染物,在不同波长光源及有氧和无氧条件下考察了Ag-TiO2薄膜的光催化活性. 结果表明,当银沉积量大于 0.0150 mg/cm2时, Ag-TiO2薄膜对紫外光的吸收发生了明显的蓝移,同时在346 nm附近出现了小的吸收峰且该峰随着银沉积量的增加逐渐向长波方向移动. 沉积在TiO2薄膜表面的银颗粒大小不均匀,主要以单质银的形式存在,也生成了部分Ag2O; 相对于TiO2薄膜, Ag-TiO2薄膜表面吸附氧的含量明显增大. Ag-TiO2薄膜的光吸收特性对其催化活性影响较大. 在低压汞灯及有氧参与的条件下,银沉积量为0.0523 mg/cm2的Ag-TiO2薄膜的催化活性最高, 其反应速率常数是TiO2薄膜的1.16倍. Ag+更易沉积在较大n值的Ag簇上,其颗粒大小不可能完全均匀. Ag-TiO2薄膜的光吸收特性、 Ag簇的大小以及Ag对O2的吸附作用是决定Ag-TiO2薄膜催化活性的主要因素.     

Photocatalytic Activity and Characterization of the Sol-Gel Derived Pb-Doped TiO2 Thin Films

Photocatalytically active Pb-doped TiO₂ thin films were prepared on a soda-lime glass substrate by sol-gel dip-coating technique using TiO₂ sols containing lead(II) nitrate. The thin films were characterized by X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), UV-VIS spectroscopy and X-ray diffraction (XRD). A shift of the UV-VIS absorption towards longer wavelengths was observed, which indicated a decrease in the band-gap of TiO₂ upon Pb doping. XRD results showed both pure and Pb-doped TiO₂ thin films were polycrystalline, anatase type, and oriented predominantly to the (101) plane. A slight shift in the d-spacing for the Pb-doped film indicated the incorporation of Pb into the TiO₂ lattice to form Pb _x Ti_1–x O₂ solid solution. AFM results showed Pb-doped TiO₂ thin films were composed of larger TiO₂ particles and had rougher surface, compared with un-doped TiO₂ thin films. XPS results showed that except for the enrichment of Pb near the surface, Pb exists in the forms of Pb _x Ti_1–x O₂ and PbO. Dimethyl-2,2-dichlorovinyl phosphate (DDVP) was efficiently degraded in the presence of the Pb-doped TiO₂ thin films by exposing the insecticide solution to sunlight. The mechanism of photocatalytic activity enhancement of the Pb-doped TiO₂ thin films was discussed.     

镧系离子掺杂TiO2的制备及其对咪唑降解反应的光催化活性

 以TiCl4和镧系元素的氯化盐溶液为前驱体,采用溶胶-凝胶法制备了不同含量镧系离子掺杂的TiO2光催化剂,用X射线衍射(XRD)、 光致发光光谱(PLS)、 表面光电压谱(SPS)和X射线光电子能谱(XPS)对催化剂进行了表征. XRD结果表明,样品为锐钛矿和金红石的混晶相,镧系离子未进入到TiO2晶格中. PLS和SPS测定结果表明,随着掺杂离子的不同和掺杂含量的不同,样品的谱强度呈现有规律的变化. 在紫外光照射下,以咪唑为目标降解物比较了催化剂的光催化活性. 结果表明,适当含量的镧系离子掺杂可有效促进TiO2表面光生载流子的分离,从而显著提高其光催化活性.     

LiF掺杂TiO2的制备及其光催化性能

采用溶胶-凝胶法制备了LiF掺杂的TiO2光催化剂,并采用X射线衍射、X射线光电子能谱和光致发光光谱等技术对样品进行了表征.以亚甲基蓝的光催化降解为反应模型,考察了LiF掺杂量、退火温度和溶液pH值对催化剂光催化性能的影响.结果表明,LiF的掺杂降低了金红石相的形成温度,同时在TiO2表面引入大量羟基氧并提高了TiO2表面氧空穴浓度,因此提高了TiO2的光催化性能.在LiF掺杂量为8%,退火温度为500℃和反应液pH值为6.6的条件下,LiF掺杂的TiO2的光催化活性是未掺杂TiO2的6倍.     

Preparation,Microstructure and Photocatalytic Activity of the Porous TiO2 Anatase Coating by Sol-Gel Processing

In this study the porous TiO² anatase coatings are prepared from alkoxide solutions containing polyethylene glycol (PEG) by a dip-coating technique. The effects of PEG addition to the precursor solution on the photocatalytic activity and microstructure of the resultant coatings are studied. The larger amount and the larger molecular weight of PEG, the larger size and more pores produced in the resultant coatings on the decomposition of PEG during heat-treatment. The adsorbed hydroxyl content of such porous coatings is found to increase due to the larger size and more pores in the coatings. However, the transmittance of the coatings decreases due to the scattering by the larger size and more pores. Photocatalytic degradation experiments show that organophosphorous insecticide, dimethyl-2,2-dichlorovinyl phosphate (DDVP), was efficiently degraded in the presence of the porous TiO₂ coatings by exposing the DDVP solution to sunlight. Photocatalytic degradation rate was related to the adsorbed hydroxyl content, transmittance and morphology of the resultant coatings.