微波闪速合成纳米ZrO_2/ZnO复合材料及其光催化性能研究

以硝酸锆和硝酸锌为原料,尿素为助燃剂,采用微波闪速法合成纳米ZrO2/ZnO复合材料,研究了纳米ZrO2/ZnO复合材料分别对甲基橙和罗丹明B的光催化降解性能。结果表明,在紫外光条件下,纳米ZrO2/ZnO复合材料光催化降解甲基橙效果明显优于罗丹明B。     

Ag＋改性SO4^2-/TiO2的制备及其光催化性能研究

本文用溶胶凝胶法制备了纳米Ag＋-SO42-/TiO2固体超强酸（AST）,采用XRD、FT-IR等方法对AST的结构进行表征,研究AST在紫外光和可见光下降解罗丹明B的光催化活性。结果表明,适宜的制备条件为：Ag＋掺杂量为0.5%,硫酸浓度为0.5mol/L,焙烧温度为450℃制备的AST具有较好的光催化活性,且在模拟可见光下AST也具有光催化活性,2h能将罗丹明B几乎完全降解。     

贝壳粉/SnS_2纳米复合材料的制备及其光催化性能的研究

采用水热法合成贝壳粉/SnS_2复合光催化材料,通过控制贝壳粉的含量制备了一系列不同质量比的贝壳粉/SnS_2纳米复合材料,探讨其光催化性能。采用XRD、DRS、IR以及SEM对制备的不同质量比的贝壳粉/SnS_2纳米复合材料进行了表征,通过在可见光下降解罗丹明B探讨了不同质量比的贝壳粉/SnS_2复合材料的光催化性能,并通过循环实验测试了样品的稳定性。结果表明,在150℃下水热反应24 h合成的质量百分比为10%的贝壳粉/SnS_2纳米复合光催化材料催化性能最好。     

Z型Ag2CO3/BiOCl异质结光催化剂的制备及其可见光催化机理分析

通过溶剂热法制备BiOCl纳米片,共沉淀法制备Ag2 CO3和复合催化剂Ag2 CO3/BiOCl,研究各材料可见光催化降解罗丹明B的效果,确定Ag2 CO3与BiOCl的最佳配比,并通过表征分析复合材料的结构和异质结光催化降解机理.结果表明,当Ag2 CO3与BiOCl的质量比为50％时,Ag2 CO3/BiOCl异...     

贝壳粉/SnS_2纳米复合材料的制备及其光催化性能的研究

采用水热法合成贝壳粉/SnS_2复合光催化材料,通过控制贝壳粉的含量制备了一系列不同质量比的贝壳粉/SnS_2纳米复合材料,探讨其光催化性能。采用XRD、DRS、IR以及SEM对制备的不同质量比的贝壳粉/SnS_2纳米复合材料进行了表征,通过在可见光下降解罗丹明B探讨了不同质量比的贝壳粉/SnS_2复合材料的光催化性能,并通过循环实验测试了样品的稳定性。结果表明,在150℃下水热反应24 h合成的质量百分比为10%的贝壳粉/SnS_2纳米复合光催化材料催化性能最好。     

α-TPMPc/TiO_2复合材料的制备及光催化性能研究

采用原位化学合成的方法合成了均匀掺杂的1,8,15,22-四苯氧基酞菁钴/二氧化钛(简称α-TP Co(Ⅱ)Pc/TiO_2)和1,8,15,22-四苯氧基酞菁铜/二氧化钛(简称α-TPCu(Ⅱ)Pc/TiO_2)复合材料。通过UV-Vis、XRD、TG进行了表征,并通过对罗丹明B的降解来考察材料的光催化性能。结果表明,α-TPMPc/TiO_2对罗丹明B降解具有较好的光催化活性,α-TPMPc敏化能有效地提高TiO_2的可见光光催化活性,且α-TPCo(Ⅱ)Pc/TiO_2的催化活性明显优于α-TPCu(Ⅱ)Pc/TiO_2。     

g-C_3N_4/LiNbWO_6光催化材料的构建及其催化性能的研究

采用一步焙烧的方法制备了新型纳米管复合材料g-C_3N_4/LiNbWO_6。采用粉末X射线衍射(XRD)、紫外-可见漫反射光谱(UV-vis-DRS)对制备的g-C_3N_4/LiNbWO_6及其前驱体进行了表征。以罗丹明B(RhB)为降解物,对纳米复合材料在可见光照射下的光催化氧化性能进行了评价。结果表明,与LiNbWO_6相比,纳米复合材料的吸收波长明显向可见光区移动,在可见光下具有更高的光降解活性。     

掺Fe~(3+) A-TiO_2粉末的制备及其光催化活性研究

在3种晶型的TiO2纳米材料中锐钛矿型的TiO2拥有最好的光催化活性。在一定条件下用水热法制备了掺Fe3+纳米锐钛矿型TiO2(A-TiO2)粉末。研究了以Fe3+A-TiO2为光催化剂对罗丹明B溶液进行可见光降解,最佳条件:在6 mg/L的酸性(pH=2)罗丹明B溶液中,加入0.153 3 g掺5%Fe3+的A-TiO2粉末,可见光照射下,室温下磁力快速搅拌反应4 h,降解率达到81.69%。     

石墨烯/二氧化钛复合材料的可见光催化性能研究

采用一步水热还原法制备出石墨烯/二氧化钛(r-GO/Ti O_2)复合材料;利用X-射线衍射、扫描电镜、红外光谱对样品的结构、形貌进行表征;以罗丹明B溶液为目标降解物,考察在可见光照射下复合材料的光催化性能。结果表明,制得的复合材料中Ti O_2颗粒大小比较均匀,粒径约为200~300 nm,Ti O_2在石墨烯片层上分散较好,石墨烯与Ti O_2成功复合;在可见光照射下,罗丹明B的降解符合一级动力学特征;r-GO/Ti O_2对罗丹明B复合降解率达到99.8%,是相同条件下制得二氧化钛的4.96倍;催化剂具有很好的重复稳定性。     

纳米材料H3PW12O40／ZrO2光催化降解染料

采用溶胶一凝胶法制备了半导体型金属氧化物ZrO2,并通过浸渍法将杂多酸H3PW12O40与其复合,获得了纳米复合光催化材料H3PW12O40／ZrO2,并在紫外光和可见光下考察了该复合材料对可溶性染料罗丹明B和亚甲基蓝的光催化活性。实验结果表明,该复合材料有较好的光催化活性。     

Graphene-ZnO nanocomposite for highly efficient photocatalytic degradation of methyl orange dye under solar light irradiation

A facile synthesis of graphene oxide-zinc oxide nanocomposite (GO-ZnO) was performed by using wet chemical method of graphene oxide and zinc acetate precursors. The nanocomposite was characterized and intercalated with Raman spectroscopy, FE-SEM, TEM, SAED and EDAX. The crystalline nature was studied from P-XRD, and surface area of the sample was analyzed by BET. The chemical composition was explained in the light of XPS phenomenon. The photo electron-excitation (PL) studies were conducted for understanding the photocatalytic mechanism, and photocatalytic degradation of methyl orange was studied by using UV-VIS spectrophotometer. We investigated the photocatalytic activity involving GO-ZnO nanocomposite besides checking the re-stability of the composite. Significant high-performance photocatalytic activity of GO-ZnO nanocomposite was exhibited on methyl orange degradation under solar light.     

Ag/Bi2 WO6的制备及光催化氧化性能

以Bi（NO3）3·5H2O、 Na2WO4·2H2O、 AgNO3为原料,利用液相沉淀法制备Bi2WO6及Ag掺杂Bi2WO6光催化剂,以亚甲基蓝溶液为目标降解物,对其降解效率进行研究。研究结果表明,当亚甲基蓝溶液的浓度为15 mg/L,体积为50 mL,降解时间3.5 h, Bi2 WO6降解率仅为55%;当Ag/Bi摩尔比为0.4%时, Ag/Bi2 WO6表现出较好的催化性能,相同时间降解率达到97%。     

Synthesis of carbon quantum dots/TiO2 nanocomposite for photo-degradation of Rhodamine B and cefradine

Pure TiO₂ and carbon quantum dots (CQDs)-doped TiO₂ nanocomposite (CQDs/TiO₂ nanocomposite) were prepared by a sol-gel approach for photocatalytic removal of Rhodamine B and cefradine. Analyses by Transmission electronmicroscopy (TEM), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), UV–visible spectroscopy and X-ray powder diffraction (XRD) confirmed the successful formation of CQDs/TiO₂ heterostructure. The as-prepared TiO₂ and CQDs/TiO₂ composite possessed small particles, spherical-like shape, and anatase crystal form. Meanwhile, Rhodamine B and cefradine were chosen to evaluate the photocatalytic activity of TiO₂ and CQDs/TiO₂ composite. Results revealed that with the facile decoration of CQDs, the absorption of photocatalyst was extended into visible light region and photocatalytic activity was improved in comparison with pure TiO₂. Furthermore, the mechanism for the improvement of the photocatalytic performance of the composites was discussed on the basis of the results. CQDs play an important role in the photocatalytic process, due to their superior ability to extend the visible absorption and produce more electrons and electron–hole pairs for the degradation of pollutants. In all, the paper offers further insights into the development of CQDs/TiO₂ nanocomposite as photocatalyst for the degradation of antibiotics.     

Hierarchical ZnO/Ag nanocomposites for plasmon-enhanced visible-light photocatalytic performance

Surface plasmon resonance (SPR) of the noble metals improve the photocatalytic activity of semiconductor metal oxides in the visible light region. This work reports the facile preparation of SPR induced visible light active hierarchical ZnO/Ag nanocomposite photocatalysts by using environmental friendly two-step method. The prepared nanocomposites analyzed by using various techniques such as powder-XRD, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, UV–Vis spectroscopy, photoluminescence spectroscopy, and photocurrent measurements. The results indicate the formation of hierarchical ZnO/Ag nanocomposites, which shows surface plasmon absorbance and enhanced photocurrent responses. Because of the SPR effect, the nanocomposites show improved visible light photocatalytic activity by enhancing the electron-hole pair separation in Rhodamine B degradation system.     

Highly visible light active Ag@ZnO nanocomposites synthesized by gel-combustion route

Highly visible light active 1% and 3% Ag@ZnO nanocomposites were synthesized via a gel combustion route using citric acid as a fuel. The formation of the nanocomposites with enhanced properties was confirmed using a range of characterization techniques, photocatalysis and photoelectrochemical studies. Compared to the pristine ZnO nanoparticles, the Ag@ZnO nanocomposites exhibited enhanced visible light photocatalytic activity for the degradation of methylene blue and photoelectrochemical response. A mechanism was proposed to account for the photocatalytic activities of the Ag@ZnO nanocomposite that showed the surface plasmon resonance (SPR) of Ag is an effective way of enhancing the visible light photocatalytic activities.     

Ag nanoparticles loaded TiO2/MWCNT ternary nanocomposite: A visible-light-driven photocatalyst with enhanced photocatalytic performance and stability

A visible light active photocatalyst, Ag/TiO₂/MWCNT was synthesized by loading of Ag nanoparticles onto TiO₂/MWCNT nanocomposite. The photocatalytic activity of Ag/TiO₂/MWCNT ternary nanocomposite was evaluated for the degradation of methylene blue dye under UV and visible light irradiation. Ag/TiO₂/MWCNT ternary nanocomposite exhibits (~9 times) higher photocatalytic activity than TiO₂/MWCNT and (~2 times) higher than Ag/TiO₂ binary nanocomposites under visible light irradiation. The enhancement in the photocatalytic activity is attributed to the synergistic effect between Ag nanoparticles and MWCNT, which enhance the charge separation efficiency by Schottky barrier formation at Ag/TiO₂ interface and role of MWCNT as an electron reservoir. Effect of different scavengers on the degradation of methylene blue dye in the presence of catalyst has been investigated to find the role of photogenerated electrons and holes. Simultaneously, the Ag/TiO₂/MWCNT shows excellent photocatalytic stability. This work highlights the importance of Ag/TiO₂/MWCNT ternary nanocomposite as highly efficient and stable visible-light-driven photocatalyst for the degradation of organic dyes.     

Novel in-situ synthesis of Au/SnO2 quantum dots for enhanced visible-light-driven photocatalytic applications

In recent years, visible-light-driven metal–semiconductor nanocomposites have emerged as a suitable material for the decomposition of various water and air pollutants. In this work, a novel plasmonic Au nanoparticle (NP)/SnO₂ quantum dot (SQD) nanocomposite photocatalysts were prepared via a one-step solvothermal technique. The as-prepared plasmonic photocatalysts were characterized by various techniques, and the results established the formation of Au/SQD nanocomposites. The photocatalytic activity of the as-prepared plasmonic Au/SQD nanocomposites was examined by the degradation of Rhodamine B (RhB) at room temperature under visible light, and the Au/SQD photocatalyst, prepared using 1.0?g of tin chloride, exhibited a higher rate constant of RhB degradation than pristine SQDs. This exceptional improvement in catalytic performance under visible light is ascribed to a shift of the band gap from the ultraviolet to the visible region. The surface plasmon resonance effect of Au NPs and the synergistic coupling of the metal and the semiconductor QDs also played a vital role in enhancing the catalytic performance. The process of the photocatalytic degradation of RhB by the Au/SQD nanocomposites under visible light is described.     

Molybdenum doped TiO2 nanocomposite coatings: Visible light driven photocatalytic self-cleaning of mineral substrates

The molybdenum doped TiO₂ nanocomposite layer double hydroxide (LDH) suspensions, Mo:TiO₂-LDHs, were synthesized by a wet impregnation method in order to enhance the pure TiO₂ (water suspension) photocatalytic activity and consequently its self-cleaning efficiency under exposure to visible light. The aim was to produce nanocomposites by a simple, energy saving and cost beneficial synthesis. The mass ratio Mo/Ti was systematically varied (0.03, 0.06, 0.09, 0.12). The obtained nanocomposite Mo:TiO₂-LDH suspensions were first characterized by UV–vis spectroscopy (band-gap energies), Zeta-sizer (particle size distribution and stability) and X-ray diffraction (XRD) (structure) and then applied onto the model mineral substrates, brick and stone. The photocatalytic activity of the obtained coating was determined based on the degradation kinetics of the Rhodamine B (RhB) under artificial visible light irradiation (white LED). The obtained results were compared to the ones of the unmodified TiO₂-LDH suspension. The obtained results also showed that all prepared nanocomposites have good photocatalytic activity, particularly the suspension Mo:TiO₂-LDH with the Mo/Ti 0.03 mass ratio which possesses the best value. In addition, as regards the visible light driven self-cleaning effect, this suspension has proven to be a good protective functional coating for porous mineral substrates (bricks and stones).     

Gd,B共掺杂改性TiO_2纳米颗粒的可见光光催化活性

采用溶胶-凝胶法制备了Gd和B共掺杂的TiO2纳米颗粒,研究了TiO2纳米颗粒在可见光下的光催化活性。应用XRD、TEM和UV-Vis等手段对TiO2纳米颗粒的物相、粒径、形貌及光学性能进行了表征。结果表明,掺杂可以抑制TiO2晶粒增长,阻碍TiO2由锐钛矿相向金红石相的转变。紫外-可见吸收光谱显示,共掺杂纳米颗粒在可见光区吸收有较强提高,共掺杂离子以协同作用拓展TiO2光谱响应,使吸收带产生红移,提高光生载流子的分离效率。光催化降解实验表明,共掺杂TiO2纳米颗粒有很高的可见光光催化活性,以500℃热处理的共掺杂摩尔比为0.005 Gd和0.04 B的TiO2纳米颗粒光催化效果最好,在可见光下对甲基橙的降解率为98.9%。     

Gd,B共掺杂改性TiO2纳米颗粒的可见光光催化活性

采用溶胶-凝胶法制备了Gd和B共掺杂的TiO2纳米颗粒,研究了TiO2纳米颗粒在可见光下的光催化活性。应用XRD、TEM和UV-Vis等手段对TiO2纳米颗粒的物相、粒径、形貌及光学性能进行了表征。结果表明,掺杂可以抑制TiO2晶粒增长,阻碍TiO2由锐钛矿相向金红石相的转变。紫外-可见吸收光谱显示,共掺杂纳米颗粒在可见光区吸收有较强提高,共掺杂离子以协同作用拓展TiO2光谱响应,使吸收带产生红移,提高光生载流子的分离效率。光催化降解实验表明,共掺杂TiO2纳米颗粒有很高的可见光光催化活性,以500℃热处理的共掺杂摩尔比为0.005 Gd和0.04 B的TiO2纳米颗粒光催化效果最好,在可见光下对甲基橙的降解率为98.9%。