[(PMo12O403-)/PAMAM-Cu2+]n多层膜的制备和电化学行为

采用层层自组装的方法,把多金属氧酸盐PMo12O403-和与Cu2+络合的聚酰胺-胺树形分子PAMAM(PAMAM-Cu2+)交替吸附成膜。X射线光电子能谱(XPS)、紫外可见光谱(UV-Vis)、原子力显微镜(AFM)和循环伏安法(CV)测试表明,PMo12O403-和PAMAM-Cu2+能通过静电作用形成多层膜且膜的增长均一稳定,该多层膜修饰电极对H2O2和NO2-有较好的电催化还原活性。     

H6PMo9V3O40/PANI复合电极材料的电容特性研究

采用超声氧化聚合法,以自制杂多酸H6PMo9V3O40作为质子酸掺杂剂兼辅助氧化剂,配合过硫酸铵(APS)氧化剂,合成了聚苯胺基复合电容材料H6PMo9V3O40/PANI。以此复合材料为活性物质制备电极,在0.5mol/L H2SO4电解液体系中,通过循环伏安、恒电流充放电和交流阻抗等技术研究其电化学性能。结果表明,H6PMo9V3O40/PANI电极体现出优良的法拉第赝电容特征,循环稳定性能良好,且大电流下充放电特征明显。在-0.1~0.7V(vs.SCE)电压和1.5A/g电流密度下,首次充电比电容量160.643F/g,放电比电容量153.225F/g,充放电效率95.38%,500次循环后,充电比电容量140.543F/g,衰减率12.51%,放电比电容量139.528F/g,衰减率8.94%,充放电效率99.27%。     

铂钌/聚苯胺/聚砜复合膜电极的制备及对甲醇的电催化氧化

利用电化学聚合分别制备了铂(Pt)及其铂钌(PtRu)/聚苯胺(PAN)/聚砜(PSF)复合膜电极。采用循环伏安法和电化学交流阻抗对复合膜电极的甲醇电催化氧化性能进行了比较与分析。结果表明:PtRu/PAN/PSF电极对甲醇的电催化活性比Pt/PAN/PSF电极的高,铂钌的沉积不仅改变了催化剂表面对氢的吸附性质,而且使氧化物还原峰电位向阴极方向移动。另外,对在不同浓度下沉积的铂钌电极对甲醇的催化效果也做了讨论,验证了RPt∶Ru=2∶1时,复合膜电极具有最好的催化活性。     

Pt/{PEI-GN/PW_(12)}_n复合膜的制备及其对甲醇氧化的电催化性能

选用水溶性高分子聚乙烯亚胺(PEI)修饰石墨烯(GN),增强石墨烯的水溶性和分散性;利用层层自组装法制备{PEI-GN/PW12}n复合膜,并以此为基底膜,用循环伏安法原位电沉积制备Pt纳米簇负载的复合膜催化剂。紫外-可见分光光度法(UV-Vis)、X射线衍射(XRD)、X射线光电子能谱(XPS)和扫描电子显微镜(SEM)等技术表征复合膜催化剂组成、形貌和结构。循环伏安法(CV)、计时电流法(It)、CO溶出伏安法及电化学阻抗等电化学方法研究结果表明,该纳米复合膜催化剂对甲醇氧化具有良好的电催化活性、稳定性及抗CO毒化能力。     

空心结构(C12H8N2)3·H3PMo12O40/WO3的制备及光催化研究

制备了杂多化合物(C12H8N2)3.H3PMo12O40和空心结构复合催化剂(C12H8N2)3.H3PMo12O40/WO3,采用等离子体原子发射光谱(ICP-AES)、元素分析(EA)、热重-差热分析(TG-DTA)、X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)、扫描电镜(SEM)、能量色散X射线谱(EDS)、紫外-可见漫反射吸收光谱(UV-vis DRS)进行了表征。在高压汞灯照射下,研究了杂多化合物(C12H8N2)3.H3PMo12O40、空心WO3微球和空心复合催化剂(C12-H8N2)3.H3PMo12O40/WO3对罗丹明B水溶液的光催化降解活性,结果表明,在复合催化剂中,杂多化合物(C12-H8N2)3.H3PMo12O40和WO3具有协同作用,光催化活性比单独的杂多化合物和WO3都高。     

石墨烯支持Pt纳米粒子修饰电极的制备及电催化活性研究

采用一步电化学法制备了石墨烯支持Pt纳米粒子修饰电极(Nano-Pt/ERGO/GCE),利用交流阻抗研究了电极的性能以及该修饰电极的电催化活性。结果表明,采用循环伏安法制备石墨烯支持Pt纳米粒子,具有制备方法简单且纳米粒子粒径可控等优点。与单独的Pt纳米粒子修饰电极相比,Nano-Pt/ERGO/GCE电极表面Pt粒子分布更均匀,对甲醇的氧化具有极强的电催化活性。研究成果在甲醇燃料电池的研发中具有潜在的应用价值。     

基于SnO2/Fe3O4粒子电极的三维电极体系的电催化性能

通过水热法合成复合金属氧化物SnO_2/Fe_3O_4粒子电极,然后采用X射线衍射(XRD)、扫描电子显微镜(SEM)、X射线光电子能谱(XPS)、磁滞回线等技术分别对粒子电极的晶体组分、形貌、元素组成和分子结构以及粒子电极的磁性特征进行表征。采用循环伏安法分析了三维电极系统的电化学性能,并进行了电催化氧化降解罗丹明B(RhB)的实验。结果表明,SnO_2/Fe_3O_4粒子电极负载稳定、导电性强、便于回收再利用,有利于电催化氧化降解反应。三维电极降解罗丹明B的析氧电流高于其他电极体系,电催化活性效果明显,90min内罗丹明B的降解率为100%、TOC去除率为83%,反应中产生的·OH是降解有机物的主要活性基。粒子电极在重复利用5次的情况下,对罗丹明B的降解率仍保持93%以上、TOC去除率保持在77%以上,具有稳定的电催化性能。     

Pt/TiO2-NTs复合材料的制备及其甲醇电氧化机理研究

采用水热法合成锐钛矿型TiO2纳米管(TiO2-NTs),并以其为载体制备了Pt/TiO2-NTs复合材料。用TEM、XRD对复合材料的形貌和结构进行了表征,TEM测试表明Pt纳米粒子以簇状形式均匀地分散在TiO2纳米管表面。运用循环伏安法研究了Pt/TiO2-NTs复合材料在不同条件下对硫酸中甲醇的电催化活性,并讨论了甲醇的电氧化机理。结果表明,Pt/TiO2-NTs复合材料具有出色的电催化活性。因此,TiO2-NTs被认为是非常有潜力的燃料电池贵金属催化剂载体材料。     

载体表面化学状态对Pt/C催化剂结构及电催化活性的影响

对碳黑进行不同条件的氧化处理得到不同表面化学状态的载体,以甲醛为还原剂,氯铂酸为前驱体,制备Pt/C电催化剂.运用X射线光电子能谱(XPS)、X射线衍射(XRD)、透射电镜(TEM)等分析手段研究碳黑及Pt/C催化剂的化学组成、化学状态、晶体结构及表面形貌,并用循环伏安法(CV)测试Pt/C催化剂对甲醇的电催化氧化.结...     

Pt-TiO2纳米管电极的制备及电催化性能

采用电化学阳极氧化-阴极还原法制备Pt-TiO2纳米管电极.扫描电镜(SEM)结果显示TiO2纳米管平均管径100nm,管长470nm,管壁厚20nm,且其比表面积大,同时纳米Pt微粒分散在TiO2纳米管上,且粒径细小,Pt微粒充分裸露,使得Pt-TiO2纳米管电极活性点多,电催化性能高.对甲醇的电催化性能测试表明:同纯Pt电极和Pt-TiO2电极(Pt微粒固定在TiO2致密膜上)相比,Pt-TiO2纳米管电极对甲醇具有更高的电催化活性,其氧化峰电流密度是在纯Pt片电极上的20倍以上.     

Preparation and electrochemical and electrocatalytic properties of nanocomposite multilayer film based on a Keggin-type phosphomolybdate

An electrostatically self-assembled multilayer film has successfully been prepared on quartz or indium-tin-oxide substrates by alternating adsorption of a Keggin-type phosphomolybdate H3PMo12O40 (PMo12) and 1,10-diaminodecane (1,10-DAD). The formation of (PMo12/1,10-DAD), film was investigated by ultraviolet (UV) spectroscopy. The UV spectra showed that the deposition of the films was uniform and reproducible. The cyclic voltammetry on the PMo12-based multilayer film indicated that the PMo12 anions in the film undergo rapid four 2e(-)/2H+ redox processes, and electrocatalytically active towards the reduction of bromate.     

Preparation and photocatalytic activity of an electrostatically self-assembled film made of [PMo12O40](3-) and a bipolar hemicyanine cation

An electrostatically self-assembled film of PMo12/H6 has successfully been prepared on quartz substrates by alternating adsorption of [PMo12O40(3-) (PMo12) and a bipolar hemicyanine derivative of (E)-1,1'-(hexane-1,6-diyl)bis(4-(4-(dimethylamino)styryl)pyridinium) bromide (H6Br2). The UV-visible spectra showed that the film was uniformly deposited and the charge transfer between two film-forming components might occur in the film. The photocatalytic performance of the film was studied for the degradation of aqueous dye Methyl Red (MR) under UV irradiation. The degradation of MR follows Langmuir-Hinshelwood first-order kinetics.     

Preparation of multiwalled carbon nanotubes-platinum-Nafion-glucose oxidase nanobiocomposite and its application to glucose biosensor

Platinum (Pt) nanoparticles were electrodeposited within multiwalled carbon nanotubes-Nafion-glucose oxidase (MWNTs-Nafion-GOx) nanobiocomposite by a potentiostatic method. The morphology and nature of the resulting MWNTs-Pt-Nafion-GOx nanobiocomposite were characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy (EDS). The electrocatalytic properties of the MWNTs-Pt-Nafion-GOx nanobiocomposite film modified glassy carbon electrode were characterized by cyclic voltammetry and amperometry in the presence of hydrogen peroxide. The glucose biosensor sensitivity was strongly influenced by the deposits of Pt nanoparticles and amount of GOx concentration within the MWNTs-Pt-Nafion-GOx nanobiocomposite film. The optimized glucose biosensor displayed a sensitivity of 640 nA mM(-1), a linear range of up to 4 mM, a detection limit of 4 microM, and a response time of less than 4 s at an operating potential of +500 mV versus Ag/AgCl (3 M KCl).     

Pt／n—n＋-Si电极上化学沉积铁氰化镍薄膜及其应用

在表面外延生长9μm的n型层的磷重掺杂的硅基底n—n＋一Si）结构上沉积约40nm铂（Pt）,经氩气保护673K热处理30min作为半导体电极（Pt／n—n＋-Si）。将半导体电极和铁氰化钾、硫酸镍以及硝酸钠的溶液接触,沉积出稳定的铁氰化镍（NiHCF）薄膜。复合电极与Pt电极组成光电化学电池,在零偏电压条件下,通过测量该电池的光电流可检测过氧化氢。通过循环伏安和X-光电子能谱对NiHCF薄膜进行了分析与表征。     

Ultrathin ruthenium(II) complex-H4SiW12O40 multilayer film

A dipolar Ru(II) complex, [(bpy)2Ru(bpbh)Ru(bpy)2](ClO4)4 {where bpbh = 1,6-bis-[2-(2-pyridyl) benzimidazoyl]hexane, bpy = 2,2'-bipyridine}, was synthesized and characterized. A multilayer film of at least 18 layers was successfully prepared by alternating adsorption of H4SiW12O40 and [Ru2(bpy)4(bpbh)](ClO4)4 by electrostatic layer-by-layer self-assembly. The multilayer films were studied by ultraviolet-visible and X-ray photoelectron spectroscopy, atomic force microscopy, and cyclic voltammetry.     

恒压电沉积Pt-Fe合金催化剂及在PEMFC阴极的应用

利用循环伏安法探究Pt与Fe共沉积的还原电位, 并在此电位下在多孔碳布表面恒压电沉积制备Pt-Fe合金, 研究其作为质子交换膜燃料电池 (PEMFC)阴极催化剂的电催化活性。通过X射线衍射 (XRD)、扫描电子显微镜(SEM)及场发射扫描电子显微镜 (FESEM)、能量色散谱 (EDS)、循环伏安 (CV)、单电池极化、电化学交流阻抗谱 (EIS)等测试技术对所得催化剂进行物理及电化学性能表征。实验表明, 在0.075 V电位下可还原得到Pt-Fe合金, 其颗粒在碳布表面呈空心球状且分散均匀; 共沉积时间对Pt-Fe合金催化剂成分组成有显著的影响, 随着时间的增加, 合金中Pt与Fe原子比增加, Fe相对含量下降。Fe可与Pt形成稳定的合金催化剂, 显著提高铂对氧还原的催化活性。电沉积30 min制得的合金催化剂具有最佳的催化活性。     

H_3PW_(12)O_(40)/PMMA/PA6夹层复合纳米纤维膜的制备及光催化性能

采用静电纺丝法制备了磷钨酸(H_3PW_(12)O_(40))/聚甲基丙烯酸甲酯(PMMA)/尼龙6(PA6)夹层复合纳米纤维膜,并通过扫描电镜、X射线能谱和红外光谱对其形貌和结构进行表征。结果显示,H_3PW_(12)O_(40)存在于夹层膜的上层与下层,且其Keggin结构未遭到破坏。与H_3PW_(12)O_(40)粉末和H_3PW_(12)O_(40)/PMMA复合纳米纤维膜相比,夹层膜对甲基橙(MO)具有更高的光催化活性。夹层纳米纤维膜易于回收并能重复使用,循环使用3次后光催化活性无明显下降,主要归咎于H_3PW_(12)O_(40)稳定地负载于纳米纤维膜中。因此,H_3PW_(12)O_(40)/PMMA/PA6夹层复合纳米纤维膜在水污染治理领域具有潜在的实际应用价值。     

硼钨铜杂多酸/聚酰胺-胺多层膜的制备及其电催化性能

通过层层自组装技术在氧化锢锡(ITO)电极上制备Keggin型硼钨铜杂多酸/聚酰胺-胺有机-无机复合多层膜.利用X射线光电子能谱(XPS),UV-Vis光谱和原子力显微镜(AFM)等手段对多层膜的组成和表面形貌进行了表征.结果表明,杂多酸阴离子和聚酰胺-胺树形分子通过静电相互作用形成了多层膜且膜的增长均匀.杂多酸阴离子...     

Preparation Ru,Bi monolayer modified Pt nanoparticles as the anode catalyst for methanol oxidation

Platinum nanoparticles were successfully electrodeposited on indium tin oxide (ITO) surface in the solution with hexachloroplatinic acid and copper ion by cyclic voltammogram method. The micrographs and structure of Pt nanoparticles were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. The electrocatalytic properties of Pt nanoparticles/ITO or modified by Ru, Bi underpotential deposition (UPD) for methanol oxidation have been investigated by cyclic voltammetry (CV) and chronoamperometry (CA). High electroactivity and good long-term stability can be observed. These results indicate that Pt nanoparticles modified by UPD may have potential applications in designing noble metal catalysts of fuel cells with low loading and high activity at the atomic level.