ZnO/PAN基纳米碳纤维膜的制备及其光催化性能的研究（英文）

采用N,N-二甲基甲酰胺(DMF)为极性溶剂溶解醋酸锌(Zn(Ac)_2·2H_2O),然后加入聚丙烯腈(PAN)制得前驱体溶液,采用静电纺丝法制备PAN/Zn(Ac)_2复合纳米纤维膜,将PAN/Zn(Ac)_2复合纳米纤维膜在真空管式炉中经过高温煅烧得到PAN基碳纤维/氧化锌(CF/ZnO)纳米纤维膜,以CF/ZnO纳米纤维膜为光催化剂,亚甲基蓝为污染物,进行光催化降解实验,研究了Zn(Ac)_2含量对PAN/Zn(Ac)_2复合纳米纤维形貌、性能的影响,以及CF/ZnO纳米纤维膜的光催化性能。结果表明:Zn(Ac)_2的掺入并未对PAN的化学结构产生影响,二者属于物理结合,Zn(Ac)_2能较均匀地分布在纤维的内部;随着Zn(Ac)_2含量的增加,CF/ZnO纳米纤维膜对亚甲基蓝的降解率会提高,当Zn(Ac)_2质量分数(相对PAN)为60%时,可见光照射80 min后CF/ZnO纳米纤维膜对亚甲基蓝的降解率达到91.6%。     

固相法合成纳米ZnO及其光催化性能研究

以Zn(NO3)2·6H2O和Na2CO3为原料、十二烷基苯磺酸钠为分散剂,采用低温固相法在350℃下制得纳米ZnO.通过XRD物相分析,发现ZnO纳米粒子样品的物相为六方晶系纤锌矿结构;TEM形貌观察,粒子基本为球形,添加表面活性剂的ZnO的平均粒径约为20 nm.水溶液中次甲基蓝染料在ZnO半导体光催化条件下、pH为9时,降解90 min,降解率达到56%.     

纳米ZnO/膨润土光催化降解亚甲基蓝研究

以Zn(NO3)2和膨润土为原料,采用沉淀法制备纳米ZnO-膨润土复合光催化材料,用FT-IR、XRD和SEM对其结构和形貌进行了表征。以高压汞灯为光源,光催化降解活性亚甲基蓝模拟染料废水,研究了ZnO/有机膨润土光催化降解性能,讨论了影响亚甲基蓝降解率主要因素。结果表明,在光照射下1.5 h,ZnO/膨润土光催化降解亚甲基蓝达96%,其重复使用降解效果保持稳定,利用该复合光催化材料降解有机染料废水是一种可行的方法。     

Au修饰纳米ZnO的超声化学法制备及光催化性能

不添加任何还原剂,利用简单的超声化学法成功制备了Au修饰纳米ZnO(Au/ZnO).以SEM、TEM、XRD、PL、UV-Vis、UV-DRS、BET等对样品进行了结构表征和性能测试.结果表明,超声化学法能够促使Au3+直接在ZnO表面被还原,Au纳米粒子沿着ZnO表面选择性生长,从而使两种材料之间形成紧密的界面结构.Au纳米粒子的修饰使得Au/ZnO在384 nm处的紫外发射峰出现蓝移,吸光度明显减弱,而绿光区荧光峰消失,表明光生电荷被有效分离.在适量的Au修饰时,Au/ZnO的紫外光吸收能力显著增强,且出现了一定程度的可见光吸收,样品光利用率得到提升.Au/ZnO能有效降解甲基橙和亚甲基蓝溶液.采用ln(ρ/ρt)=kt进行线性拟合,对样品的光催化降解性能进行动力学分析,当Au含量为0.5％(以ZnO物质的量为基准,下同)时,Au/ZnO对亚甲基蓝和甲基橙一级降解反应速率常数分别约为纯ZnO的4.26和2.38倍,降解率均达到100％.     

ZnO/氧化石墨烯复合材料的制备及其可见光催化性能

以均匀沉淀法制备纳米ZnO,并将其负载在氧化石墨烯(GO)上制得了ZnO/GO复合材料。XRD、TEM、UV、PL等证实在GO表面分散着颗粒均匀的ZnO纳米颗粒,GO与ZnO纳米颗粒之间存在电子转移效应,抑制ZnO中光生电子空穴对的复合,提高了ZnO的可见光催化性能;考察了复合材料在模拟太阳光条件下降解亚甲基蓝的光催化性能,当GO添加量为10%时,模拟太阳光照射90 min后,对亚甲基蓝的降解率达到97.2%,经过10次循环使用后降解率没有明显降低,复合材料的可见光催化活性明显优于纯的纳米ZnO,同时ZnO/GO复合材料对部分工业染料也有很好的降解活性。     

ZnO/氧化石墨烯复合材料的制备及其可见光催化性能?

以均匀沉淀法制备纳米ZnO,并将其负载在氧化石墨烯(GO)上制得了ZnO/GO复合材料。XRD、TEM、UV、PL等证实在GO表面分散着颗粒均匀的ZnO纳米颗粒,GO与ZnO纳米颗粒之间存在电子转移效应,抑制ZnO中光生电子空穴对的复合,提高了ZnO的可见光催化性能;考察了复合材料在模拟太阳光条件下降解亚甲基蓝的光催化性能,当GO添加量为10%时,模拟太阳光照射90 min后,对亚甲基蓝的降解率达到97.2%,经过10次循环使用后降解率没有明显降低,复合材料的可见光催化活性明显优于纯的纳米ZnO,同时ZnO/GO复合材料对部分工业染料也有很好的降解活性。     

纳米四氧化三铁降解亚甲基蓝的研究

在浸没循环撞击流反应器中通过共沉淀法,以氨水为沉淀剂,以FeCl3.6H2O和FeSO4.7H2O为原料制备了磁性纳米Fe3O4粒子。采用XRD、TEM等多种方法对制得的纳米粒子的结构和性能进行了表征,并研究了磁性纳米Fe3O4粒子对亚甲基蓝的降解作用。结果表明,纳米Fe3O4粒子具有相对较小的粒径;当溶液pH值为4.2、H2O2加入量为2 mL.L-1时,用0.9 g.L-1的Fe3O4悬浊液对10 mg.L-1的亚甲基蓝溶液进行降解,5 min内亚甲基蓝的降解率可达96.5%。     

Ag掺杂ZnO纳米纤维的制备及其光催化性能

采用静电纺丝技术制备了PVP/Zn(CH3COO)2、PVP/Zn(CH3COO)2/Ag NO3复合纳米纤维,经煅烧后分别得到Zn O纳米纤维和Ag/Zn O复合纳米纤维。利用SEM、TG、FTIR、XRD对煅烧前后的纤维形貌和结构进行表征。用紫外灯作为光源,以亚甲基蓝为目标降解物,考察了Zn O和Ag/Zn O复合纳米纤维的光催化活性。结果表明:银的掺入能有效地提高Zn O对亚甲基蓝的光催化降解性能,且降解性能随着Ag质量分数的增加而逐渐提高。     

La-Gd共掺ZnO纳米棒的性能及其应用研究

利用KH560交联剂来提高La-Gd/ZnO纳米棒阵列在棉织物上的牢度。以硝酸锌和六亚甲基四胺为原料,聚乙二醇2000为形貌控制剂,KH560为交联剂,采用低温水浴法制备在棉织物表面原位生长的La-Gd/ZnO纳米棒阵列。同时利用X射线衍射仪、扫描电子显微镜和紫外-可见光漫反射等方法对制备的样品进行表征和性能分析。结果表明:3%La-3%Gd/ZnO纳米棒具有良好的光催化性能,在紫外光下照射150 min,对亚甲基蓝溶液(MB)的降解率为92.15%;太阳光下照射8 h,对亚甲基蓝溶液(MB)的降解率为87.59%。且经过整理后的棉织物的抗紫外线指数UPF值由10.06提升至420.21。经水洗10次,其光催化性能仅下降1.3%,抗紫外线指数基本没有变化。     

ZnO纳米棒的制备及其光催化活性研究

以Zn(Ac)2·2H2O、NaI和N2H4·H2O为原料,在未使用任何表面活性剂的简单水热反应体系中制得了ZnO纳米棒.采用X射线粉末衍射仪(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)对产物的晶体结构、形貌进行了表征分析,并对其光催化活性进行了探讨,以ZnO纳米棒为光催化剂对有机染料污染物甲基橙进行了光催化降解实验.实验结果表明,氧化锌纳米棒对甲基橙的光催化降解具有很好的催化作用,在紫外光照射120min后,对甲基橙的降解率接近完全.     

核壳型PS@ZnO纳米复合材料的制备及其光催化性能

以单分散性良好的聚苯乙烯（PS）微球为模板,采用化学浴沉淀法制备了PS@ZnO纳米复合材料。利用SEM、TEM、XRD、FTIR和DRS等测试手段对样品的形貌、结构、组成和光学性质进行表征,在紫外光照射下进行亚甲基蓝溶液的光催化降解研究,并考察复合材料的光催化性能。结果表明：该方法制备的PS@ZnO纳米复合材料具有核壳结构,颗粒均匀,呈球形,核的平均粒径约为200nm,壳层厚度约20nm,具有良好的光催化性能,且其催化效率比单纯ZnO提高了13%,而且可以重复使用。     

A synergistic approach to light-free catalysis using zinc oxide embedded multi-walled carbon nanotube paper

Nanoparticle embedded carbon nanotube papers can produce flexible functional films, whose function is based on the electronic coupling of the nanoparticles with the network of carbon nanotubes. Here we report on the expansion of a synergistic light-free catalyst system that requires both the molecular wire capability of multi-walled carbon nanotubes and the piezoelectric properties of ZnO nanoparticles. The electron–hole pairs can be induced by the piezoelectric effect of ZnO nanoparticles under the effect of pressure. The strong oxidizing radicals interact with the electron–hole pairs and aqueous solution to induce the degradation of methylene blue without the requirement of light. This study highlights the use of nanoparticles for the piezoelectric – light free catalyst system and the limitations of increased nanoparticle loading on the catalytic degradation of methylene blue.     

A facile solid-state heating method for preparation of poly(3,4-ethelenedioxythiophene)/ZnO nanocomposite and photocatalytic activity

Poly(3,4-ethylenedioxythiophene)/zinc oxide (PEDOT/ZnO) nanocomposites were prepared by a simple solid-state heating method, in which the content of ZnO was varied from 10 to 20 wt%. The structure and morphology of the composites were characterized by Fourier transform infrared (FTIR) spectroscopy, ultraviolet-visible (UV-vis) absorption spectroscopy, X-ray diffraction (XRD), and transmission electron microscopy (TEM). The photocatalytic activities of the composites were investigated by the degradation of methylene blue (MB) dye in aqueous medium under UV light and natural sunlight irradiation. The FTIR, UV-vis, and XRD results showed that the composites were successfully synthesized, and there was a strong interaction between PEDOT and nano-ZnO. The TEM results suggested that the composites were a mixture of shale-like PEDOT and less aggregated nano-ZnO. The photocatalytic activity results indicated that the incorporation of ZnO nanoparticles in composites can enhance the photocatalytic efficiency of the composites under both UV light and natural sunlight irradiation, and the highest photocatalytic efficiency under UV light (98.7%) and natural sunlight (96.6%) after 5 h occurred in the PEDOT/15wt%ZnO nanocomposite.     

单壁碳纳米管显著增强的ZnO可见光催化活性

利用醋酸锌为原料,采用溶胶-凝胶法制备了单壁碳纳米管（SWMTs）和氧化锌的纳米复合物（ZnO/SWNTs）。用X射线衍射光谱（XRD）、拉曼光谱、扫描电子显微镜（SEM）、透射电子显微镜（TEM）、热重分析（TGA）、傅里叶变换红外光谱（FT-IR）以及紫外-可见吸收光谱（UV-Vis）对复合物进行了表征。结果显示,粒径为10～20 nm的ZnO粒子均匀地负载在SWNTs表面,且在可见光区具有很好的光吸收性能。研究了ZnO/SWNTs光催化剂在太阳光照射下对甲基橙和亚甲基蓝的光催化降解情况。结果表明,复合物的催化活性明显高于ZnO。对于甲基橙,光照200 min后,降解率为99.8%,是纯ZnO（4.8%）的20倍;对于亚甲基蓝,仅光照20 min,降解率就达到了98.4%,是纯ZnO（4.0%）的25倍。     

Transition metal doped ZnO nanoparticles with enhanced photocatalytic and antibacterial performances: Experimental and DFT studies

Transition metal doped ZnO (TM-ZnO) nanoparticles with 3% dopant content are successfully prepared via a simple solvothermal route. This work highlights Mn, Fe, Co, Ni or Cu ions as the dopant transition metals. The as-prepared samples are wurtzite phase ZnO crystals, and the average sizes of undoped ZnO and TM-ZnO nanoparticles range from 200 nm to 400 nm. XPS studies confirm that the transition metal ions are successfully doped into the crystal lattice of ZnO. The band gaps of the undoped ZnO and TM-ZnO crystals are calculated by using UV-DRS spectroscopic measurements. The visible light response of ZnO nanomaterials is improved by doping transition metal ions. For investigating the influence of transition metal doping on the photocatalytic performance of ZnO, the photodegradation rate of methylene blue (MB) is investigated under simulated sunlight irradiation. The photocatalytic properties of ZnO doped with transition metals are improved at different degrees, among which Cu-doped ZnO exhibits the best photocatalytic performance. Based on density functional theory (DFT) calculation result, a possible photocatalytic mechanism is proposed. Furthermore, the antibacterial performance of Cu-doped ZnO is investigated by selecting E. coli, under simulated sunlight irradiation and remarkable sterilization of E. coli is achieved.     

氧化锌/辉沸石复合光催化材料的制备及其性能

以七水硫酸锌为前驱体,天然辉沸石为载体,以直接沉积法制备了纳米氧化锌/辉沸石复合材料。结合XRD、BET和SEM等表征手段对样品的物相组成、孔结构特性及微观形貌做了检测分析,并且探究了不同氧化锌负载量及煅烧温度对纳米氧化锌/辉沸石复合材料降解亚甲基蓝性能的影响规律。结果表明：复合材料实现了六方铅锌矿相氧化锌与辉沸石的紧密复合与有效分散,且该复合结构能够有效抑制光生载流子的复合,改善材料的吸附性能,进而提高材料的光催化效率;当复合材料中氧化锌负载量为30%（氧化锌与沸石的质量比）、煅烧温度为300 ℃时,材料对亚甲基蓝的光催化性能最优。     

Efficient solar light photocatalytic degradation of commercial pharmaceutical drug and dye using rGO-PANI assisted c-ZnO heterojunction nanocomposites

The major requirement of a solar light-activated photocatalyst is the effective utilization of the light-induced electron-hole pair and exciton lifetime. Herein, the reduced graphene oxide and polyaniline assisted carbon doped porous ZnO (c-ZnO) heterojunction nanocomposites (RPZ nanocomposites) were designed for enhanced photocatalytic degradation of the commercially available pharmaceutical antibiotic drug amoxicillin and clavulanate potassium (ACP) and methylene blue (MB) dye using natural sunlight. The surface morphology, phase purity, and bonding environment of the prepared RPZ heterojunction nanocomposite were analyzed using scanning electron microscopy, X-ray diffraction, and soft X-ray absorption spectroscopy, respectively. In comparison with pure ZnO, a doping and composite formation reduced the bandgap energy from 3.34 to 2.80 eV, calculated using the Tauc plot. From photocatalytic degradation studies, the as-prepared RPZ heterojunction nanocomposite efficiently degraded 95% and 47% of MB dye and ACP in 100 min under natural sunlight with the reaction rates of 0.0296 and 0.0055 min^?1, respectively. The removal efficiency of the photocatalyst was obtained to be 95% and 46.14% for MB dye and ACP, respectively.     

Pr3+:Y2SiO5/ZnO-TiO2/ACF复合材料的制备及其光催化性能

采用溶胶-凝胶法将ZnO掺杂进荧光粉/TiO_2体系,并以活性炭纤维(ACF)为载体,制备了Pr~(3+)∶Y_2SiO_5/ZnO-TiO_2/ACF复合材料。采用XRD、SEM、EDS、FS和UV-vis DRS,对材料的结构及性能进行了表征,并以亚甲基蓝为模拟降解物,考察了ZnO掺杂量对复合材料可见光催化性能的影响。结果表明,当ZnO掺杂质量为TiO_2质量的10%时,制得的复合材料光催化性能最强,在500 mL质量浓度为15 mg/L的亚甲基蓝溶液中反应12 h后亚甲基蓝去除率高达98.0%,反应符合拟一级动力学方程,反应速率常数为0.341 3 h~(-1),是未掺杂ZnO的Pr~(3+)∶Y_2SiO_5/TiO_2/ACF的1.75倍,复合材料重复使用4次后亚甲基蓝去除率仍然保持在85%以上。     

纳米CuO/CoFe2O4-TiO2模拟太阳光降解亚甲基蓝的性能

采用溶胶-凝胶法制备CuO/CoFe2O4粒子,并与P25复合制备纳米催化剂CuO/CoFe2O4-TiO2.通过模拟太阳光催化降解亚甲基蓝,对催化剂活性进行研究,采用SEM、TEM、XRD和UV-Vis DRS方法对催化剂进行表征.结果表明,CuO/CoFe2O4粒子均匀分散在P25微粒表面,平均粒径为60 nm.并...     

Preparation of reusable glass hollow fiber membranes and methylene blue adsorption

In this work, the PVDF/glass as-prepared composite membrane was prepared through phase-inversion method and used to adsorb methylene blue dye. The results of SEM and BET showed that the membrane had an asymmetric nanoscale porous structure. The electronegativity on the surface of membrane was determined through zeta potential test. The adsorption properties of as-prepared composite membrane and glass membrane were studied through testing the removal ratio of methylene blue from aqueous solution. Then the effects of membranes dose, pH value, temperature and initial concentration on the removal ratio were systematically studied. The adsorption mechanism was also studied. The adsorption kinetics and adsorption isotherm fitted well with the pseudo-second-order model and Freundlich model, respectively. In addition, the adsorption efficiency of glass membrane basically remained 85% after eight repeated adsorption-calcination cycles. The obtained membranes could be reused for methylene blue removal with high efficiency for multiply times.