Property Characterization and Photocatalytic Activity Evaluation of BiGdO3 Nanoparticles under Visible Light Irradiation

BiGdO₃ nanoparticles were prepared by a solid-state reaction method and applied in photocatalytic degradation of dyes in this study. BiGdO₃ was characterized by X-ray powder diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, Brunauer-Emmett-Teller, UV-Vis diffuse reflectance spectroscopy and transmission electron microscopy. The results showed that BiGdO₃ crystallized well with the fluorite-type structure, a face-centered cubic crystal system and a space group Fm3m 225. The lattice parameter of BiGdO₃ was 5.465 angstrom. The band gap of BiGdO₃ was estimated to be 2.25 eV. BiGdO₃ showed a strong optical absorption during the visible light region. Moreover, the photocatalytic activity of BiGdO₃ was evaluated by photocatalytic degradation of direct dyes in aqueous solution under visible light irradiation. BiGdO₃ demonstrated excellent photocatalytic activity in degrading Direct Orange 26 (DO-26) or Direct Red 23 (DR-23) under visible light irradiation. The photocatalytic degradation of DO-26 or DR-23 followed the first-order reaction kinetics, and the first-order rate constant was 0.0046 or 0.0023 min⁻¹ with BiGdO₃ as catalyst. The degradation intermediates of DO-26 were observed and the possible photocatalytic degradation pathway of DO-26 under visible light irradiation was provided. The effect of various operational parameters on the photocatalytic activity and the stability of BiGdO₃ particles were also discussed in detail. BiGdO₃/(visible light) photocatalysis system was confirmed to be suitable for textile industry wastewater treatment.     

TiO2单晶面负载贵金属Ag的形貌及其催化活性

90%以上高暴露单晶面TiO2(001),(101)和(010)以水热法合成,并通过光沉积方法负载贵金属Ag;在相同的负载条件下,由于不同晶面具有不同的原子排布和电子结构,其负载的Ag的粒径不同,TiO2(101)晶面上Ag的平均粒径最小,TiO2(001)晶面上Ag的平均粒径最大,Ag的粒径大小顺序：Ag/TiO2-101相似文献   

Preparation of Si doped molecularly imprinted TiO2 photocatalyst and its degradation to antibiotic wastewater

TiO₂, molecularly imprinted TiO₂ (TiO₂/OTC) and a novel Si doped molecularly imprinted TiO₂ (TiO₂/SiO₂/OTC) nano photocatalytic materials were prepared by liquid phase deposition method. The products were characterized by XRD and SEM. The photocatalytic activities of the samples were evaluated by the photocatalytic degradation of oxytetracycline wastewater under a xenon lamp irradiation. The results showed that TiO₂/SiO₂/OTC and TiO₂/OTC could improve both the photocatalytic activity and the molecular recognition ability, while the photocatalytic activities of TiO₂/SiO₂/OTC sample was more effective than TiO₂/OTC sample with 5 times reuse. The photocatalytic activity of TiO₂/SiO₂/OTC photocatalyst sample had a greater improvement and its photocatalytic degradation of oxytetracycline wastewater reached 80.79% in 120 minute reaction.     

高岭土-ZnO光催化氧化—萃取脱除汽油中硫的研究

采用水热法制备了高岭土-ZnO复合光催化剂,以噻吩的正辛烷溶液作为汽油的模型化合物,研究了萃取剂种类、剂油比、空气通入量、催化剂的用量及高岭土负载量等对光催化氧化-萃取脱硫效果的影响。结果表明,当空气通入量为150 m L/min,负载20%的高岭土-ZnO用量为1.5 g/L,400 W金卤灯光照180 min后,用N,N-二甲基甲酰胺(DMF)按剂油比为0.5:1萃取,脱硫率达90%以上。     

La3+掺杂TiO2光催化降解染料废水的研究

采用溶胶-凝胶法制备了稀土La3+掺杂的TiO2催化剂,并用XRD对其进行表征,用催化剂对染料媒介漂兰B进行降解处理,考察影响降解率的因素.结果表明,La3+掺杂的TiO2降解效果较纯TiO2好,当La3+掺杂摩尔分数为0.5％,媒介漂兰B的质量浓度为20 mg/L,体系pH值为3,催化剂用量为1.5 g/L时,染料废水降解率可达97.7％.     

Photocatalytic Degradation of p-Cresol by Zinc Oxide under UV Irradiation

Photocatalytic degradation of p-cresol was carried out using ZnO under UV irradiation. The amount of photocatalyst, concentration of p-cresol and pH were studied as variables. The residual concentration and mineralization of p-cresol was monitored using a UV-visible spectrophotometer and total organic carbon (TOC) analyzer, respectively. The intermediates were detected by ultra high pressure liquid chromatography (UPLC). The highest photodegradation of p-cresol was observed at 2.5 g/L of ZnO and 100 ppm of p-cresol. P-cresol photocatalytic degradation was favorable in the pH range of 6-9. The detected intermediates were 4-hydroxy-benzaldehyde and 4-methyl-1,2-benzodiol. TOC studies show that 93% of total organic carbon was removed from solution during irradiation time. Reusability shows no significant reduction in photocatalytic performance in photodegrading p-cresol.     

Fe3+掺杂Bi2MoO6光催化剂的合成及其活性研究

以钼酸铵、硝酸铋和硝酸铁为原料,采用水热/溶剂热法合成了铁掺杂的钼酸铋光催化剂,用X-射线粉末衍射、扫描电镜及紫外-可见吸收光谱等进行表征,并以罗丹明B为模型污染物,考察了纳米钼酸铋对罗丹明B溶液的光催化降解活性;以噻吩作为典型的含硫污染物,评价样品的光催化氧化脱硫活性。结果表明,Fe元素掺杂导致Bi2 MoO6的尺寸下降,比表面积增大;Fe掺杂,Bi2 MoO6吸收边发生红移;光催化活性与Fe元素的掺杂浓度有关,当掺杂量为0.5%时,活性最高;Fe掺杂Bi2MoO6对模拟汽油具有较好的脱硫活性,模拟可见光照射3 h,可使用模拟汽油的硫含量降低至70μg/g以下,脱硫率达到89%。     

Microwave absorption and photocatalytic properties of magnetic nickel nanoparticles/recycled PET nanofibers web

Abstract

The use of nanoparticles in electrospun web has always been of great interest for a wider and easier application especially for microwave absorption and photocatalytic activity. In this work, nickel nanoparticles/recycled poly (ethylene terephthalate) nanofibers web (Ni NPs/RPET NFs web) were electrospun from a homogeneous sonicated RPET solution containing Ni NPs with an average diameter of 32.5?nm synthesizedthrough the chemical reduction method. To study morphologies, crystalline structure, magnetic, wettability, microwave absorption and photocatalytic activities of the web, field emission-scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and electromagnetic properties were used. The saturation magnetization of the Ni NPs/RPET NFs web at a nickel concentration of 3% was 0.5?emu/g. In addition, the wettability, the reflection coefficient, the absorption coefficient, the EMI shielding and the photocatalytic activities of the Ni NPs/RPET NFs web were improved compared to the RPET NFs web.     

硫化锑改性二氧化钛电极板的制备及其光电催化作用

采用化学沉积法,以三氯化锑为原料,与Na2S2O3水溶液混和,浸渍二氧化钛氧化铟锡镀膜玻璃电极（ITO/TiO2电极板）制成改良型电极。利用紫外吸收光谱（UV-vis）,紫外可见漫反射光谱（DRS）,X射线衍射（XRD）,扫描电子显微镜（SEM）等方法对样品进行表征。结果表明,Sb2S3沉积效果明显;在波长400 nm至624 nm的可见光范围内,该薄膜有强烈的吸收;循环伏安法的测定确定该电极板具有可见光的响应能力,并且光电转化率为3.4%。