Sn4+-TiO2的制备及其光催化降解苯酚的研究

采用硬脂酸法制备出Sn4+-TiO2复合光催化剂,用透射电子显微镜和X射线衍射仪对粉体的粒径、物相、形貌和热稳定性进行了表征.通过粉体对苯酚的降解情况对其光催化活性进行了测试,结果表明,与纯TiO2相比,Sn4+-TiO2的光催化活性有较大提高,当SnO2的掺入量为摩尔比5.0%时催化活性最高.     

Sn4+-TiO2的制备及其光催化降解苯酚的研究

采用硬脂酸法制备出Sn4+-TiO2复合光催化剂,用透射电子显微镜和X射线衍射仪对粉体的粒径、物相、形貌和热稳定性进行了表征.通过粉体对苯酚的降解情况对其光催化活性进行了测试,结果表明,与纯TiO2相比,Sn4+-TiO2的光催化活性有较大提高,当SnO2的掺入量为摩尔比5.0%时催化活性最高.     

铁掺杂纳米TiO2的制备及其光催化性能研究

采用溶胶-凝胶法制备了掺杂Fe3 的纳米TiO2微粒,采用X光衍射仪对粉体进行了表征.以甲基橙为目标降解物,研究了Fe3 掺杂纳米TiO2光催化性能.结果表明,掺杂适量Fe3 能够提高TiO2的光催化活性,当Fe3 的掺入量为摩尔比0.41%时催化活性最高.以紫外灯为光源,降解初始浓度为20mg·L-1的250mL甲基橙溶液,催化剂0.41%(摩尔分数)Fe3 -TiO2投加量为0.5g时,甲基橙的光催化降解效果最好.     

Ce4+/TiO2溶胶对酸性藏青GGR的光催化降解

以钛酸四正丁酯为前驱体,采用溶胶-凝胶法常温制备稀土离子Ce4+掺杂的TiO2溶胶,用以光催化降解酸性藏青GGR,探究掺杂对TiO2溶胶光催化活性的影响.研究Ce4+掺杂量、pH、溶胶浓度和染料初始浓度对溶胶光催化活性的影响.结果表明:未掺杂TiO2溶胶粒径为29.7nm,随Ce4+掺杂量增加粒径逐渐降低至22.4nm,粒径的减小使得TiO2粒子比表面积加大,光催化活性提高.染料降解率随掺杂量增加而提高,当Ce4+的掺杂量超过1.0％时,降解率下降,说明过量的掺杂会抑制TiO2的光催化活性.溶胶pH会影响溶胶中TiO2晶型和带电情况,pH为1-2时溶胶光催化活性最高.溶胶浓度低光催化反应体系中TiO2受激发产生的电子和空穴少,染料降解率低.染料初始浓度高紫外光透过率小,光能利用率低,染料降解速度慢.当溶胶pH为1-2,溶胶浓度0.2mol·L-1,染料初始浓度59mg· L-1时,未掺杂TiO2溶胶对酸性藏青GGR的降解率为64.5％,摩尔掺杂比1.0％的Ce4+/TiO2对染料的降解率达90.2％.掺杂使TiO2的光催化活性提高了25.7％.     

尖晶石型铁氧体CaxZn1-xFe2O4的制备及其光催化性能研究

采用改进的溶胶-凝胶法制备CaxZn1-xFe2O4粉体。用X射线粉末衍射仪(XRD)对样品进行结构表征,随着Ca2+掺杂量的增加,样品出现CaFe2O4的衍射峰。使用扫描电子显微镜(SEM)对样品进行形貌表征,结果表明样品的形貌呈不规则的颗粒状,且颗粒大小为2μm,并显现出片层堆叠情况。通过对甲基橙进行光催化降解实验,对CaxZn1-xFe2O4粉体的光催化活性进行了研究。结果表明,经过Ca2+掺杂的CaxZn1-xFe2O4样品,光催化活性明显提高。     

Sm3+和Gd3+共掺杂TiO2粉体的制备和性能表征

采用溶胶-凝胶法制备了纯TiO2,1%Sm3+或2%Gd3+单掺杂和1%Sm3+/2%Gd3+共掺杂TiO2复合粉体,采用XRD和SEM/EDAX等技术进行表征。以对亚甲基蓝的光催化降解为目标反应,评价了TiO2复合粉体的光催化活性,探讨了Sm3+/Gd3+共掺杂、亚甲基蓝初始浓度和粉体投加量对TiO2粉体光催化活性的影响机制。结果表明,Sm3+/Gd3+共掺杂可以显著提高TiO2粉体的光催化活性;Sm3+/Gd3+共掺杂在TiO2粉体中产生协同作用,抑制了TiO2由锐钛矿相向金红石相转变,使TiO2粒径尺寸减小,增大了TiO2的晶格畸变。当亚甲基蓝初始浓度为4mg/L和粉体投加量为2g/L时,TiO2复合粉体的光催化活性最高,对亚甲基蓝光催化降解率达99.71%;降解亚甲基蓝反应符合Langmuir-Hinshelwood动力学方程。     

Fe_3O_4/Ce~(3+)-TiO_2复合光催化材料的制备及其光催化性能研究

采用溶胶-凝胶法,以钛酸四丁酯、硝酸铈为主要原料,无水乙醇为溶剂,冰醋酸为抑制剂,浓硝酸为催化剂制得稳定的Ce3+掺杂TiO2溶胶,其凝胶经不同温度煅烧3 h后制得Ce3+掺杂量不同的TiO2粉体。用XRD对TiO2进行了测试对比分析,以紫外光为光源,亚甲基蓝溶液为模拟有机染料废水,研究了TiO2的光催化性能。用化学共沉淀法制备了具有强磁性的纳米Fe3O4水基磁流体,再与Ce3+掺杂TiO2进行复合,制备了Fe3O4负载量不同的磁性Ce3+掺杂TiO2,研究了其对亚甲基蓝的光催化降解效果、磁分离回收率的影响。结果表明,TiO2凝胶热处理温度、Ce3+掺量、TiO2晶型及Fe3O4负载量对亚甲基蓝的光催化活性均有影响。掺Ce3+量为1%,热处理温度650℃的Ce3+掺杂TiO2粉体光催化活性最高。Fe3O4负载量为10%的Fe3O4/Ce3+-TiO2对亚甲基蓝的降解率8 h时达到90.3%,磁分离回收率达96.8%。     

不同煅烧温度及气氛制备Gd~(3+)-C~(4+)掺杂TiO_2的光催化活性

为了研究Gd3+、C4+离子掺杂Ti O2粉体的光催化活性,选取不同Gd3+、C4+加入量、煅烧温度、气氛等因素,采用溶胶-凝胶法制备Gd3+-C4+掺杂Ti O2复合粉体;通过X射线衍射、显微图像观察、表面及孔隙度分析等手段对复合粉体的物相、形貌及光催化活性进行表征。结果表明:Gd3+-C4+掺杂Ti O2复合粉体在N2气氛中经550℃煅烧2 h后,粉体分散较好,Ti O2仍为锐钛矿结构;当Gd3+与C4+的物质的量比为0.06时,复合粉体在太阳光下照射3 h后,对罗丹明B的降解率可达90%。     

WO_3-TiO_2纳米材料的制备及其光催化性能

采用溶胶-凝胶法制备WO3-TiO2纳米复合材料,并用透射电镜和X射线衍射对所制备材料进行表征和分析。以WO3-TiO2纳米材料为光催化剂对甲基橙进行光催化降解处理,研究WO3的掺杂量、煅烧温度、光照时间等因素对甲基橙降解率的影响。结果表明:在紫外灯照射下,使用w(WO3)=3%、550℃下煅烧得到的WO3-TiO2纳米复合粉体0.02 g,甲基橙溶液20 mL(ρ=5 mg/L,pH=4),光催化3 h后,甲基橙降解率达到94.93%。     

尖晶石型掺杂镉锡酸锌的制备与光催化性能

采用化学共沉淀法制各了尖晶石型掺杂镉的Zn2SnO4粉体.通过X射线粉末衍射(XRD)进行表征,利用紫外可见吸收光谱(UV-Vis)测试技术,研究粉体结构及不同掺杂量对光催化活性的影响,确定最佳掺杂量和热处理温度.以波长λ=312nm的光源对茜素红水溶液进行光催化降解实验,讨论光催化剂用量、染料浓度、催化剂焙烧温度及时间、试液的pH值、光照时间等与染料脱色率的关系.结果表明,该复合氧化物粉体属立方晶系,组成为(CdO.06ZnO.94)2SnO4.在实验条件下,cd+的加入使Zn2SnO4的光催化活性明显提高.     

V-N共掺杂TiO_2/玻璃珠光催化复合材料的制备及光催化性能

用溶胶-凝胶法制备V-N-TiO_2/玻璃珠光催化复合材料,研究V-N-TiO_2(V-N-TiO_2)的浓度、V-N-TiO_2/玻璃珠的浸渍次数、玻璃珠尺寸、煅烧温度和煅烧时间对V-N-TiO_2/玻璃珠光催化复合材料光催化性能的影响。采用XRD、EDS、TEM、XPS等测试手段对复合材料的结构和性能进行表征;在100 W汞灯下,以苯酚溶液为目标降解物,对V-N-TiO_2/玻璃珠光催化复合材料光催化性能进行测定。研究表明:当V-N-TiO_2/玻璃珠的浸渍次数为4次、玻璃珠尺寸为2~3mm、煅烧温度为400℃和煅烧时间为4.5h时,得到的V-N-TiO_2/玻璃珠光催化复合材料对苯酚的光催化性能最佳,且单位催化剂对苯酚的降解量略高于V-N-TiO_2。V-N-TiO_2/玻璃珠光催化复合材料既易于回收,又具有良好的光催化性能。     

复合电沉积法制备Sn-TiO2纳米薄膜

采用复合电沉积法制备了TiO2质量分数为20.86%的Sn-TiO2纳米薄膜,研究了阴极电流密度、镀液温度、TiO2微粒的悬浮量等因素对薄膜中TiO2含量的影响,采用扫描电子显微镜(SEM)、X射线衍射(XRD)对热处理后的SnO2-TiO2复合薄膜进行了表征,以甲基橙为模型化合物对薄膜的光催化性能进行了测定.结果表明,在最佳工艺下所得复合纳米薄膜具有优异的光催化活性.     

Catalytic wet air oxidation of phenol over CeO2-TiO2 catalyst in the batch reactor and the packed-bed reactor

CeO2-TiO2 catalysts are prepared by coprecipitation method, and the activity and stability in the catalytic wet air oxidation (CWAO) of phenol are investigated in a batch reactor and packed-bed reactor. CeO2-TiO2 mixed oxides show the higher activity than pure CeO2 and TiO2, and CeO2-TiO2 1/1 catalyst displays the highest activity in the CWAO of phenol. In a batch reactor, COD and TOC removals are about 100% and 77% after 120 min in the CWAO of phenol over CeO2-TiO2 1/1 catalyst at reaction temperature of 150 degrees C, the total pressure of 3 MPa, phenol concentration of 1000 mg/L, and catalyst dosage of 4 g/L. In a packed-bed reactor using CeO2-TiO2 1/1 particle catalyst, over 91% COD and 80% TOC removals are obtained at the reaction temperature of 140 degrees C, the air total pressure of 3.5 MPa, the phenol concentration of 1000 mg/L for 100 h continue reaction. Leaching of metal ions of CeO2-TiO2 1/1 particle catalyst is very low during the continuous reaction. CeO2-TiO2 1/1 catalyst exhibits the excellent activity and stability in the CWAO of phenol.     

Effect of filler types and calcination temperature on the microstructure and the nitric oxide photocatalytic activity of composite titanium dioxide films

The composite titanium dioxide (TiO(2)) films coating on the woven glass fabric were prepared by a modified sol-gel process, using pre-calcinated TiO(2) nanoparticle or silica gel as filler. The characterized physicochemical properties of the prepared catalyst films showed that the specific surface area, the microstructure and the crystal structure of the catalysts were greatly affected by the fillers and the calcination temperature. The physicochemical properties of composite films and the photocatalytic activity of nitric oxide (NO) show that the pre-calcinated TiO(2) nanoparticle is more favorable than silica gel as filler. The pre-calcinated TiO(2) nanoparticle filler can increase the photocatalytic activities of the catalysts by increasing the specific surface area, introducing a bimodal mesoporous structure, and creating a polymorphous crystal structure. And the TiO(2)-TiO(2) film calcinated at 400 degrees C exhibits the highest photocatalytic activity for NO oxidation and is more active than Degussa P25.     

Visible Light Induced Photocatalysis of Cerium Ion Modified Titania Sol and Nanocrystallites

The cerium ion(Ce4+) doped titania sol and nanocrystallites were prepared by chemical coprecipitation-peptization and hydrothermal synthesis methods, respectively. The X-ray diffraction pattern shows that Ce4+-TiO2 xerogel powder has semicrystalline structure and thermal sintering sample has crystalline structure. Ce4+-TiO2 nanocrystallites are composed of the major anatase phase titania (88.82 wt pct) and a small amount of crystalline cerium titanate. AFM micrograph shows that primary particle size of well-dispersed ultrafine sol particles is below 15 nm in diameter. The particle sizes are 30 nm for xerogel sample and 70 nm for nanocrystallites sample, which is different from the estimated values (2.41 nm and 4.53 nm) by XRD Scherrer's formula. The difference is mainly due to aggregation of nanocrystallites. The experimental results exhibit that photocatalysts of Ce4+-TiO2 sol and nanocrystallites have the ability to photodegrade reactive brilliant red dye (X-3B ) under visible light irradiation with t     

磁性分子筛催化剂的制备及其性能

以改性Fe3O4颗粒为核,采用溶胶-凝胶法在Fe3O4核表面包覆SiO2壳层,并在SiO2孔道内负载纳米TiO2颗粒,得到易于固-液分离、平均直径为90~150 nm的具有核壳结构的Fe3O4-TiO2-MCM-41光催化剂复合颗粒,采用透射电镜、X射线衍射、X射线光电子能谱等手段对样品进行表征,并对该催化剂的光催化性能进行测试。结果表明:所制备的磁性分子筛催化剂在紫外光下对苯酚的降解率达94.12%,对重金属离子Cr6+的吸附能达到95.05%。     

Nylon6-TiO_2杂化超细纤维的制备与表征

采用静电纺丝法制备了Nylon6-TiO2及其杂化超细纤维无纺布。使用SEM、TEM和FTIR等方法探讨了其微观形貌、结构,并通过抗菌性能方法验证其抗菌性能与不同金属离子掺杂Nylon6-TiO2纤维膜的关系。结果表明：Ag＋的掺杂可改善电纺纤维的形貌特征,使纤维尺寸均匀,珠状物减少;Cu2＋的掺杂降低了Nylon6-...     

Fabrication characterization and activity of a solar light driven photocatalyst: cerium doped TiO2 magnetic nanofibers

A novel magnetic separable composite photocatalytic nanofiber consisting of TiO2 as the major phase, CeO(2-y) and CoFe2O4 as the dopant phase was prepared by sol-gel method and electrospinning technique, and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-vis diffuse reflectance spectrum (UV-vis DRS) and vibrating sample magnetometer (VSM). The photocatalytic activity of the resultant CoFe2O4-TiO2 and CeO(2-y)/CoFe2O4-TiO2 nanofibers was evaluated by photodegradation of methylene blue (MB) in an aqueous solution under xenon lamp (the irradiation spectrum energy distribution is similar to sunlight) irradiation in a photochemical reactor. The results showed that the dopant of Ce could affect the absorbance ability and photo-response range. The sample containing 1.0 wt% CeO(2-y) exhibited the highest degradation with 35% for MB under simulate solar light irradiation. Furthermore, the as-synthesized composite photocatalytic nanofibers could be separated easily by an external magnetic field, thus it might hold potential for application in wastewater treatment.     

超级电容器用CeO_2-MnO/3D石墨烯复合材料的制备

以西瓜瓜瓤为碳源,采用两步碳化法制备三维石墨烯(3D-Fiberbased Graphene,3D G)材料,并使用水热法制备了CeO_2-MnO/3DG复合材料,以期获得比电容高,循环寿命好的石墨烯超级电容器电极材料。结果表明:3DG材料具有较高比表面积,最高可达到332m~2·g~(-1)。CeO_2-MnO/3DG复合材料具有三维导电网络结构,金属氧化物颗粒在石墨烯片层间生长均匀,粒径在10nm左右。电化学测试结果显示:在0.5 mol·L~(-1)的Na_2SO_4溶液中,电流密度1A·g~(-1),当摩尔比MnO∶CeO_2=4∶1,复合负载量在80%时得到的CeO_2-MnO/3D G复合材料拥有最高比电容,达308.5F·g~(-1),经过1 000次循环充放电测试比电容保持率为95.5%。CeO_2-MnO/3DG复合材料电化学性能的提高主要是因为两种金属氧化物复合负载与石墨烯的协同作用。     

Bi_2S_3-BiOCl/煤矸石复合光催化剂的制备及光催化性能

以表面改性煤矸石粉、Bi(NO_3)_3·5H_2O和NH_4Cl为原料,采用超声化学法制备了BiOCl/煤矸石前驱体;并通过BiOCl/煤矸石前驱体和硫代乙酰胺(TAA)的阴离子交换反应,原位制备了Bi_2S_3-BiOCl/煤矸石复合光催化剂。利用XRD和SEM对Bi_2S_3-BiOCl/煤矸石复合光催化材料的结构及表面形貌进行了表征,并以可见光为光源,甲基橙为目标降解物,对其光催化活性进行了研究。结果表明:在可见光辐照下,Bi_2S_3-BiOCl/煤矸石复合光催化剂表现出较高的光催化降解能力,这是由于Bi_2S_3与BiOCl复合后形成的异质结促进了光生电子和光生空穴的分离,抑制了它们的复合。