铍、氮共掺杂TiO2的制备及其可见光下光解水制氢性能研究

通过煅烧硫酸钛与氨水水解沉淀物制备氮掺杂TiO2(N-TiO2),用浸渍法制备了铍、氮共掺杂TiO2光催化剂(Be-N-TiO2).通过可见光光还原沉积法载铂,以可见光(λ≥420nm)光催化制氢为探针反应考察了催化剂的活性,发现当煅烧温度为300℃,Be2 的掺杂量为1.5%(原子分数)时,制备的Pt/Be-N-TiO2制H2活性最高.通过XRD、DRS、FT-IR等手段对掺杂催化剂进行了表征,N掺杂可在TiO2中形成O-Ti-N键,使其具有可见光吸收能力;掺入Be2 可以有效的分离光生电子和空穴,减少了两者的复合,同时能够消除由于氮掺杂引入的氧空位,使共掺杂催化剂相对于单一的N-TiO2具有较高的可见光制H2活性.     

Preparation of Ti3+/N-co-doped TiO2 by one-step hydrothermal synthesis method with high photocatalytic degradation performance under visible light

Journal of Materials Science: Materials in Electronics - Ti3+/N-co-doped TiO2 was successfully synthesized in situ by one-step hydrothermal method using tetrabutyl titanate (TBOT) as the titanium...     

非金属元素掺杂TiO2的可见光催化活性研究进展

TiO2(锐钛矿)的禁带宽度限制了其光诱导特性的广泛应用,非金属元素掺杂为TiO2在可见光辐射环境下的应用提供了新的机会.详细介绍了非金属元素(N、C、S、F)掺杂TiO2的制备方法和可见光催化活性研究的最新进展,讨论了制备工艺与掺杂TiO2可见光催化活性的关系,深入分析了非金属元素对TiO2可见光催化活性的诱导机理.制备工艺显著影响了掺杂元素的化学态和含量,从而决定了掺杂TiO2带隙中局域态的特征.带隙中局域态特征正是影响掺杂TiO2可见光催化活性的关键因素.文章也对未来的研究方向进行了展望.     

Ag@AgCl改性Bi4Ti3O12的制备及其可见光催化性能

以五水硝酸铋为铋源、钛酸四丁酯为钛源,通过水热法制备了Bi4Ti3O12,再以硝酸银为银源、盐酸为氯源,采用光照还原Bi4Ti3O12得到Ag@AgCl/Bi4Ti3O12复合材料.利用XRD、UV-Vis DRS、SEM、TEM、BET和XPS等方法对所制备材料的组成和结构进行表征和分析,并以甲基橙(MO)溶液的脱色...     

纳米光催化剂Sm2InNbO7的制备及其可见光产氢活性

采用溶胶-凝胶法制备了纳米光催化剂Sm2InNbO7,通过XRD、FE-SEM、BET以及UV-Vis DRS测试对该材料的结构、粒径、比表面积和光吸收性能进行了表征。结果表明,Sm2InNbO7的晶粒尺寸和比表面积与柠檬酸(CA)加入量和煅烧温度有关。着重考察了不同条件下制备的Sm2InNbO7系列催化剂的光催化分解水产氢活性。实验结果表明,当CA与金属阳离子(Nb5++Sm3++In3+)的物质的量的比为2、煅烧温度为1073K时,获得的Sm2InNbO7纳米粉体具有最高的光催化产氢活性,测得的8h内平均产氢速率为8.32μmol/h,为固相法制备的Sm2InNbO7粉体的产氢速率的2.2倍。     

Synthesis and characterization of Ag/TiO2-B nanosquares with high photocatalytic activity under visible light irradiation

Square-like B doped TiO₂ nanocrystals were first synthesized by a mild solvothermal method with H₃BO₄ and titanium isopropoxide as the precursors, and isopropyl alcohol as reaction medium. Then, Ag nanoparticles were deposited on TiO₂-B nanosquares by photo-deposition. The as-synthesized products have been investigated by photocatalytic reaction test and characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and UV–vis diffuse reflectance spectra (DRS). The results showed that boron was successfully doped into TiO₂ nanosquares under solvothermal condition. The obtained Ag/TiO₂-B composite showed high efficiency in degradation of acid orange II under visible light irradiation. The high photocatalytic performance could be attributed to the synergistic effect of B doping and the plasmon photocatalysis role of the deposited silver nanoparticles over TiO₂.     

氮钒共掺TiO_2的表征及其对甲醛的可见光催化性能

以钛酸丁酯为Ti源,六次甲基四胺为N源,偏钒酸铵为V源,利用溶胶-凝胶法制备氮钒共掺杂二氧化钛(N-V-TiO2)纳米材料。采用XRD、UVVis、BET、XPS等检测手段对N-V-TiO2的晶型比例、元素组成等进行分析,研究其在可见光下催化氧化甲醛气体的性能。结果表明,煅烧温度500℃、掺氮28%、掺钒1%的N-V-TiO2具有混晶型结构、比表面积大、对可见光吸收强,催化降解甲醛的效率最高可达到91.6%,分别比纯TiO2、掺氮TiO2、掺钒TiO2的效率显著提高。N-V-TiO2光氧化效率随甲醛初始浓度增大而减小,光催化反应服从一级反应动力学特征,而且包括吸附和光催化氧化反应两部分,其中光催化氧化为速控步骤;重复5次使用的效率仍然高于单独掺杂TiO2。     

Preparation of Fe-doped TiO2 nanotube arrays and their photocatalytic activities under visible light

Fe-doped TiO₂ nanotube arrays have been prepared by the template-based liquid phase deposition method. Their morphologies, structures and optical properties were investigated by scanning electron microscopy, transmission electron microscopy, X-ray diffraction and UV-vis absorption spectroscopy. Their photocatalytic activities were evaluated by the degradation of methylene blue under visible light. The UV-vis absorption spectra of the Fe-doped TiO₂ nanotube arrays showed a red shift and an enhancement of the absorption in the visible region compared to the undoped sample. The Fe-doped TiO₂ nanotube arrays exhibited good photocatalytic activities under visible light irradiation, and the optimum dopant amount was found to be 5.9 at% in our experiments.     

Bi2O2CO3/TiO2复合粉体的制备及其光催化性能研究

采用水热法制备了Bi2O2CO3,并将其与TiO2进行了复合。XRD数据表明此复合光催化剂中Bi2O2CO3结晶性良好,紫外-可见漫反射光谱说明Bi2O2CO3的加入使其吸收带边有一定的红移。研究了紫外-可见光照射下Bi2O2CO3/TiO2复合光催化剂对亚甲基蓝溶液的降解性能,结果表明当Bi2O2CO3与TiO2的质量比为0.032时,得到性能最优的复合光催化剂,其光催化活性优于TiO2。     

Oxygen-vacancy-rich Ag/Bi5O7Br nanosheets enable improved photocatalytic NO removal and oxygen evolution under visible light exposure

Photocatalytic NO removal is a green and sustainable alternative to the conventional thermocatalysis in the conversion of NO to nitrates. However, the efficiency of photocatalytic NO removal is restricted by weak NO adsorption and high charge recombination on photocatalyst. Herein, we report on one-step synthesis of Ag/Bi₅O₇Br nanosheets with rich oxygen vacancies (OVs) by a facile liquid phase reduction method. Under visible light irradiation on oxygen-vacancy-rich Ag/Bi₅O₇Br for 50 min the photocatalytic NO removal ratio is up to 64.65%, which is about 1.6 times higher than that by using pristine Bi₅O₇Br. The average oxygen production rate is 823 μmol·g^?1·h^?1, which is nearly 10 times higher than that of Bi₅O₇Br. Density functional theory (DFT) calculations reveal that OVs incorporation and plasmonic Ag can synergistically strengthen NO adsorption on Bi₅O₇Br. This work highlights the great potential of defects and plasmonic metals on synergistic enhancement in photocatalytic NO removal and oxygen evolution.     

Co-deposition of Ag and Co3O4 on black TiO2-x nanotubes with enhanced photocatalytic activity under visible light irradiation

Journal of Materials Science - Due to the development of industries, environmental problems attract much attention, and photocatalyst degradation of dye materials has been considered an effective...     

复合光催化剂CdS-Pt/TiO_2低温制备及可见光制氢性能

用不同方法制备了CdS-Pt/TiO2复合光催化剂。催化剂通过X射线衍射、比表面和紫外-可见漫反射吸收进行了表征。以可见光光解水制氢为探针反应,考察了CdS-Pt/TiO2复合光催化剂的可见光活性。结果表明制备方法极大地影响CdS-Pt/TiO2复合光催化剂的活性。低结晶度的CdS与Pt/TiO2复合形成的CdS-Pt/TiO2复合光催化剂具有最高的可见光活性,其光解水的量子效率为6.95%。     

Synthesis of one-dimensional TiO2/V2O5 branched heterostructures and their visible light photocatalytic activity towards Rhodamine B

We present the synthesis and visible-light-induced catalytic activity of one-dimensional (1D) TiO(2)/V(2)O(5) branched heterostructures. The 1D TiO(2)/V(2)O(5) heterostructures were prepared by RF reactive magnetron sputtering of V(2)O(5) onto electrospun TiO(2) nanofibers. Then, the samples were annealed at 300?°C for 2 h in air ambient to form the 1D TiO(2)/V(2)O(5) branched heterostructures. The photodecomposition rate of Rhodamine B (RhB) by the 1D TiO(2)/V(2)O(5) branched heterostructures under visible light was much faster than that of pure TiO(2) nanofibers, revealing that the visible-light-induced catalytic activity of the 1D TiO(2)/V(2)O(5) branched heterostructures was greatly improved. The enhancement of the photocatalytic activity of the 1D TiO(2)/V(2)O(5) branched heterostructures can be ascribed to the coupling with a small bandgap semiconductor material V(2)O(5), where the absorption range is extended, the photogenerated electrons and holes are highly separated and the surface charge carrier transfer rate is promoted.     

可见光响应N掺杂TiO2的制备及光催化性能研究

以NH4Cl为氮源,采用溶胶-凝胶法制备了具有可见光活性的N掺杂TiO2,并用X-射线衍射、傅立叶转换红外光谱进行了表征.研究表明,在pH=3、灼烧温度为500℃时,N掺杂TiO2活性最佳.在此条件下制备的N掺杂TiO2在可见光(λ＞400nm)下对4-氯酚具有良好的降解作用,而未掺杂的TiO2几乎没有,这表明掺杂进入TiO2晶格的N原子是N掺杂TiO2具有可见光活性的主要原因.     

Fabrication of magnetic ZnO/ZnFe2O4/diatomite composites: improved photocatalytic efficiency under visible light irradiation

Journal of Materials Science: Materials in Electronics - The magnetic recoverable ZnO/ZnFe2O4/diatomite (ZZFDT) composite was synthesized by hydrothermal-precipitation method. The structure,...     

Preparation of novel CdS-graphene/TiO2 composites with high photocatalytic activity for methylene blue dye under visible light

In this study, CdS combined graphene/TiO₂ (CdS-graphene/TiO₂) composites were prepared by a sol–gel method to improve on the photocatalytic performance of TiO₂. These composites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and transmission electron microscopy (TEM). The photocatalytic activities were examined by the degradation of methylene blue (MB) under visible light irradiation. The photodegradation rate of MB under visible light irradiation reached 90·1% during 150 min. The kinetics of MB degradation were plotted alongside the values calculated from the Langmuir–Hinshelwood equation. 0·1 CGT sample showed the best photocatalytic activity, which was attributed to a cooperative reaction between the increase of photo-absorption effect by graphene and photocatalytic effect by CdS.     

TiO2/碳纳米短管复合体的制备及光催化性能的研究

采用溶胶-凝胶法制备了TiO2/碳纳米短管复合体,利用X射线衍射仪(XRD)、差热-热重分析仪(TG-DTA)、扫描电子显微镜(SEM)和紫外-可见光谱仪(UV-vis)对复合体的过程和微观结构进行了分析,结果表明:短管与钛酸丁酯的质量比为1%,热处理温度为500℃时,光催化降解活性艳红X-3B效果最好,同时TiO2与碳纳米短管的复合造成TiO2的吸收谱线蓝移.