硫掺杂石墨烯电催化降解偶氮染料RBK5

采用改进的Hummers方法制备氧化石墨烯（GO）,以二苯二硫醚（BDS）为掺杂剂,在一氧化碳（CO）氛围下,采用一步退火法合成硫掺杂石墨烯（SG）。通过透射电子显微镜（TEM）、傅氏转换红外线光谱分析（FTIR）、拉曼光谱（Raman）、X射线光电子能谱（XPS）等对样品的微观结构和形貌进行表征,利用电化学阻抗技术测试杂化后石墨烯电导性能,以RBK5为目标污染物进行硫掺杂石墨烯电催化性能研究。研究结果显示,经S掺杂后的石墨烯具有高于纯石墨烯的导电能力与催化活性,当退火温度为400℃且S∶C（质量比）=1.31时,得到的硫掺杂石墨烯（400℃-SG-1.31）在初始pH为3.0时对偶氮染料RBK5的降解效果最好。在初始浓度5mg/L,电流密度为20mA,初始pH为3.0条件下,反应20min即可达到99%的RBK5降解效率。     

硫掺杂石墨烯电催化降解偶氮染料RBK

采用改进的Hummers方法制备氧化石墨烯(GO),以二苯二硫醚(BDS)为掺杂剂,在一氧化碳(CO)氛围下,采用一步退火法合成硫掺杂石墨烯(SG)。通过透射电子显微镜(TEM)、傅氏转换红外线光谱分析(FTIR)、拉曼光谱(Raman)、X射线光电子能谱(XPS)等对样品的微观结构和形貌进行表征,利用电化学阻抗技术测试杂化后石墨烯电导性能,以RBK5为目标污染物进行硫掺杂石墨烯电催化性能研究。研究结果显示,经S掺杂后的石墨烯具有高于纯石墨烯的导电能力与催化活性,当退火温度为400℃且S∶C (质量比)=1.31时,得到的硫掺杂石墨烯(400℃-SG-1.31)在初始pH为3.0时对偶氮染料RBK5的降解效果最好。在初始浓度5mg/L,电流密度为20mA,初始pH为3.0条件下,反应20min即可达到99%的RBK5降解效率。     

不锈钢基PbO2电极电催化氧化降解甲基橙性能的研究

本研究以自制的不锈钢基PbO2电极对25mg·L^-1的甲基橙溶液进行电催化氧化降解。考察了电流密度、支持电解质浓度、溶液pH值、温度等因素对甲基橙脱色率的影响,确定了电催化氧化甲基橙的最佳反应条件,即电流密度为50mA/cm^2,支持电解质Na2SO4的浓度为0．04mol·L^-1,降解20min后,甲基橙脱色率可达到90％以上。本研究还对几种不同印染废水进行了电催化氧化降解,结果表明,不锈钢基PbO2电极对不同的印染废水均有较好的脱色效果。     

Ti/nanoTiO_2-PAn复合膜电极催化降解甲基橙

利用溶胶-凝胶法和电化学聚合制得Ti/nanoTiO₂-PAn复合膜电极,并通过X射线衍射仪（XRD）、扫描电子显微镜（SEM）及循环伏安法（CV）对制备的Ti/nanoTiO₂-PAn复合膜电极的结构、表面形貌和性能进行了表征。以此电极对偶氮染料甲基橙进行了催化降解处理,研究了初始浓度、不同电极等因素对甲基橙电催化氧化降解的影响,结果表明Ti/nanoTiO₂-PAn复合膜电极对甲基橙具有较高的电催化氧化活性,其电催化活性优于Ti/nanoTiO₂电极。     

CoZnAl水滑石薄膜电极光电催化性能研究

采用共沉淀方法合成CoZnAl水滑石,进行了XRD和UV-vis表征,并测试了CoZnAl水滑石修饰电极的光电催化性能。考察了溶液pH、电解质溶液种类、电解质浓度等对光电催化过程的影响。结果表明,水滑石修饰薄膜电极的甲基橙降解效果最明显,降低溶液pH、采用高浓度NaNO_3作电解质,在偏酸性条件下甲基橙降解效果较好,4 h甲基橙脱色率可达83%。     

电解质对甲基橙电催化氧化性能影响研究

以自制DSA电极为阳极,采用电催化氧化法对甲基橙模拟染料废水进行降解研究。分别考察了Na_2SO_4、FeCl_3、(NH_4)_2Fe(SO_4)_2、NaCl 4种电解质对甲基橙废水降解效果的影响。结果表明,不同电解质对甲基橙电催化氧化性能影响不同。以FeCl_3、(NH_4)_2Fe(SO_4)_2为电解质时,甲基橙降解效果较差,可能降解过程中铁与中间产物形成了更难降解的铁有机络合物种;以NaCl、Na_2SO_4为电解质降解效果较好,反应2h甲基橙去除率达到97%以上;但以NaCl为电解质,反应过程中仍会形成新的难降解中间物;最佳电解质为Na_2SO_4,在降解过程中无明显中间产物出现积累,最终甲基橙被彻底矿化为CO_2和H_2O。     

新型Bi2O3/石英柱粒子电极对甲基橙的降解研究

通过浸渍焙烧法制备了Bi2O3/石英柱粒子电极,分别采用了扫描电子显微镜、能量色散X射线能谱和X射线衍射等表征手段对粒子电极的形貌、晶相和组成进行了表征。通过对甲基橙的降解,证明了粒子电极的电催化活性并优化了粒子电极反应参数。结果表明,氧化铋成功地负载在石英柱表面,且表明了三斜相的氧化铋具有良好的电催化性能;在电解电压为9V,粒子投加量为15g,初始质量浓度为200mg/L,电解质浓度为1g/L,曝气量为8L/min,处理120min后,对甲基橙的去除率可以达到95%,能耗为7.8kWh/kg(以COD计),明显优于二维电极体系,且经过5次重复使用后,粒子电极依然具有良好的电催化性能。     

bio-Pd/C气体扩散电极的电Fenton体系降解甲基橙

采用生物法合成Pd/C催化剂,制备成bio-Pd/C气体扩散电极降解甲基橙模拟废水,考察了电流大小、pH、曝气条件对甲基橙去除效果的影响,探讨了bio-Pd/C气体扩散体系下的电催化降解机制。结果表明,所制备的催化剂中Pd以无定形态存在并高度分散在生物炭内部连通的孔隙中,形状比较规则,粒径为10～15 nm。反应30 min后,bio-Pd/C气体扩散体系对甲基橙的去除率达到99%、对TOC的去除率达到53%。增大电流、低pH、增加曝气均有利于甲基橙的降解,在bio-Pd/C气体扩散体系中掺杂Pd催化剂可以强化甲基橙的降解。     

TiO2-SiO2/GAC粒子电极的制备及其对氨氮废水去除的探究

采用溶胶-凝胶法制备TiO_2-SiO_2/GAC粒子电极,通过SEM、 XRD和N_2吸附-脱附对负载前后的活性炭粒子电极进行表征。通过紫外-可见分光光度法,比较二维和三维电催化体系中羟基自由基(·OH)的瞬时浓度大小。以氨氮废水为目标污染物进行三维电催化氧化降解实验,考察了初始pH值和槽电压对氨氮降解效率的影响。结果表明,在初始pH值为10,槽电压为10 V条件下,氨氮降解效率为91.89%。     

活性炭载CeO2/Sb2O5三维电极电催化氧化降解甲基橙

采用活性炭载CeO／Sb2O5修饰三维电极电催化氧化甲基橙水溶液，发现了该电极体系具有特殊的高COD去除率，且可以有效降解乙酸；研究了甲基橙初始浓度、负载电压、初始pH值、溶液中含盐量、体系温度，甲基橙初始浓度等对甲基橙脱色率和COD去除率的影响，确定了适宜的反应条件。并对其可能机理进行了推测，在适宜的条件下，该体系对甲基橙水溶液的脱色率和COD去除率均可达90％以上。     

Thiourea assisted one-pot easy synthesis of CdS/rGO composite by the wet chemical method: Structural,optical, and photocatalytic properties

We report on the synthesis of CdS/reduced graphene oxide (rGO) composite by a wet chemical method. Thiourea was used both as a sulfur source and as a reducing agent to convert graphene oxide to rGO. The structural and morphological confirmation for the reduction of graphene oxide and the formation of the CdS/rGO composite was demonstrated by X-ray diffractometry, Raman spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy analyses. Photoluminescence spectra of the composite exhibited a more efficient luminescence quenching in comparison with pure CdS nanoparticles. The composite demonstrated 99% photodegradation of methyl orange under UV irradiation, which is much superior than the photodegradation of methyl orange under similar conditions exhibited by CdS nanoparticles (72%).     

Apo/PbSe复合材料的制备及其光催化性能

利用脱铁铁蛋白制备的纳米材料具有尺寸可控、单一等优点,在催化方面同样具有很大优势。本文以脱铁铁蛋白为模板,硒脲为硒源,乙酸铵与乙酸铅为原料,通过模板合成法和两步法制备脱铁铁蛋白/硒化铅(apo/PbSe)复合材料,采用透射电子显微镜(TEM)、X射线衍射仪(XRD)、X射线能谱仪(EDS)、紫外-可见分光光度计(UV-vis)、荧光光谱仪(PL)等手段分析材料,并测定了apo/PbSe复合材料在可见光下对废水染料甲基橙的催化降解性能。结果表明,蛋白质内部的矿物核心主要物质为PbSe,成功合成了apo/PbSe复合光催化剂。复合光催化剂的最佳实验条件为溶液pH=3.0,H₂O₂质量分数9%,此时对甲基橙的降解效率最高可达97.10%,五次循环降解实验证明了其光催化效率的稳定性。基于以上结果,说明apo/PbSe具有良好的催化活性和稳定性,并提出了apo/PbSe复合材料对甲基橙的光催化降解机理。     

The synthesis of shape-controlled polypyrrole/graphene and the study of its capacitance properties

Polypyrrole (PPy)/graphene nainocomposite was prepared by methyl orange (MO) reactive template. By changing the amount of MO, the morphology of PPy can be controlled to range from nanoparticle to nanowire. Transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction results demonstrated that the composites were successfully synthesized. The different morphologies of PPy/graphene nanocomposites had certain effects on the supercapacitor performance. The experimental results showed that the capacitance of PPy (nanoparticle)/graphene was higher than that of PPy (nanowire)/graphene. As a model, PPy (nanoparticle)/graphene was used to construct a supercapacitor. By changing the amount of pyrrole monomer, the performance of the supercapacitor prepared from different PPy content was studied in detail.     

石墨烯/TiO2的氯化改性及其新式自由基反应

成功制备了一系列石墨烯/TiO₂复合材料并分别氯化改性。以甲基橙和苯酚作为目标污染物,进行复合材料光催化降解活性实验;随后引入电化学和电子顺磁共振技术对该催化剂及其反应体系进行表征,推断其机理。结果表明,石墨烯具有极好的电子迁移能力,可以提高光生载流子的传递效率,进而增强TiO₂紫外催化性能。新型复合材料均表现出较高的光催化降解活性,甲基橙降解率由70%提升至100%,苯酚降解率由10%提升至100%。而表面氯化引入了新的活性基团,在光照条件下能够生成氯自由基,进而配合羟基、超氧,形成一种新的三自由基反应体系,使其氧化降解能力大幅提升。     

氨基化氧化石墨烯界面聚合制备超薄复合纳滤膜

采用氨基化氧化石墨烯（NGO）为界面聚合水相单体,制备了超薄复合纳滤膜。研究采用傅里叶变换红外光谱（FTIR）、X射线光电子能谱（XPS）、透射电子显微镜（TEM）、扫描电子显微镜（SEM）、原子力显微镜（AFM）表征了NGO以及复合纳滤膜的化学组成和形貌。系统考察了水相单体浓度、有机相单体浓度对于制备的超薄复合纳滤膜性能的影响。该超薄复合膜在低压（0.2 MPa）下纯水通量可达27.8 L·m^-2·h^-1,对小分子染料有较高的截留率（甲基橙截留率74.8%,橙黄钠截留率96.0%,刚果红截留率98.5%,甲基蓝截留率99%）,对于无机盐的截留率较低（Na₂SO₄截留率21.4%,MgSO₄截留率10.7%,NaCl截留率5.3%,MgCl₂截留率1.5%）,展现出优异的染料/盐分离性能。同时制备的复合纳滤膜展现了较好的长周期稳定性以及抗污染特性。     

Enhanced photocatalytic activity of Ag doped TiO2 nanoparticles synthesized by a microwave assisted method

Pure anatase TiO₂ photocatalyst with different Ag contents was prepared via a controlled and energy efficient microwave assisted method. The prepared material was further characterized by several analytical techniques like X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), surface area measurement (BET), Fourier transform-infrared spectroscopy (FT-IR), diffused reflectance spectroscopy (DRS), and thermogravimetric–differential thermal analysis (TGA–DTA). A 10 nm average crystallite size with nano-crystals of pseudo-cube like morphology was obtained for optimal (0.25 mol%) Ag doped TiO₂. The present research work is mainly focused on the enhancement of degradation efficiency of methyl orange (MO) by doping of Ag in TiO₂ matrix using UV light (365 nm). A 99.5% photodegradation efficiency of methyl orange was achieved by utilizing 0.25 mol% Ag doped TiO₂ (1 g/dm³) at pH=3 within 70 min. Recyclability of photocatalyst was also studied, with the material being found to be stable up to five runs.     

混晶型TiO_2/凹凸棒土纳米复合材料的光催化性能

以TiCl4和凹凸棒土(ATP)为原料制备了TiO2/ATP纳米复合材料,用XRD和TEM对所得样品进行了表征,并在紫外光下将此复合材料用于降解甲基橙.研究了溶液pH值、催化剂投料量、甲基橙初始质量浓度和反应时间等条件对甲基橙降解率的影响.XRD和TEM显示凹凸棒土的表面包裹着平均粒径约为10 nm的混晶型纳米二氧化钛.光催化实验结果表明,在pH值为1～4、纳米复合材料的投料量为1.0 g/L、甲基橙初始质量浓度为0.01 g/L和光催化反应时间为4 h的情况下,甲基橙的降解率可达90%以上.     

Pulsed laser ablation in liquid synthesis of ZnO/TiO2 nanocomposite catalyst with enhanced photovoltaic and photocatalytic performance

In this work, we employed an impurity-free nanoparticle synthesis technique, known as pulsed laser ablation in liquid (PLAL), to integrate titanium dioxide nanoparticles (TiO₂ NPs) into zinc oxide nanorods (ZnO NRs) with varying relative proportions. The main objective of this integration was to enhance the charge carrier separation of photo-generated electron hole pairs during solar irradiation. For the synthesis process, an Nd:YAG laser at 532 nm wavelength was applied as an ablation source, along with deionized water as a solvent medium in which the precursor materials were dispersed prior to laser irradiation. The nanocomposites were characterized by X-ray diffraction (XRD), UV–vis absorption and in-situ Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HR-TEM) and field emission scanning electron microscopy (FE-SEM). The synthesized nanocomposites were primarily utilised in two applications: firstly, as a catalyst in the degradation of methyl orange (MO) and secondly, as photo-anode in dye sensitized solar cell (DSSC). Our research has demonstrated that optimal performance was obtained for the nanocomposite containing 10% and 90% (by weight) TiO₂ NPs and ZnO respectively, which we define as the ideal nanocomposite. Relative to pure ZnO, the photo-conversion efficiency of the ideal composite was improved substantially by 63.73%, whilst the photo-degradation rate was enhanced by 3 fold. The oxidation state and the microstructural of the segregated ideal nanocomposite confirms that oxygen vacancy defects were created when perfect surface integration occurs between TiO₂ and ZnO. Nonetheless, we believe that the performance enhancement is predominantly due to the excellent charge carrier separation and fast interfacial electron flow in this nanocomposite.     

Synthesis and characterization of polyurethane/reduced graphene oxide composite deposited on steel

There has been an ongoing effort by the coatings industry to improve surface properties in order to increase corrosion and wear resistances, as well as other material properties. In this work, we report a methodology for producing nanocomposite films of polyurethane and graphene oxide and polyurethane and reduced graphene oxide. The coatings were applied on steel. The nanocomposites coatings were characterized by optical microscopy, scanning electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, contact angle measurements, and electrochemical impedance spectroscopy. Corrosion tests reveal that the use of reduced graphene oxide increases corrosion resistance when compared with the use of graphene oxide as filler.