稀土Gd掺杂对SnO2电催化电极性能影响的研究

采用浸渍法、溶胶-凝胶法,以SnCl4·5H2O、Sb2O3、Gd(NO3)3为前驱体,制备了稀土Gd掺杂SnO2涂层电极及SnO2电极.以苯酚为目标有机物,研究了不同稀土掺杂量、不同制备方法所获得电极的电化学降解特性,确定了较适宜的稀土掺杂量和制备方法.在本实验条件,稀土掺杂量(原子质量比)为SnSbGd=10061条件下制备的电催化电极性能最好,溶胶-凝胶法制备的电极其电催化性能及稳定性能均优于浸渍法制备的电极.对所制备的稀土Gd掺杂电极及空白电极进行了TOC测试、UV扫描分析及SEM、XRD、XPS等表征,分析并讨论了稀土掺杂对SnO2电极性能的影响机理.结果表明,稀土Gd的掺杂有利于SnO2电极电催化性能的提高,而且不同稀土掺杂量对SnO2电极性能影响并不相同.     

Sb掺杂钛基SnO2电极的制备、表征及其电催化性能研究

采用电沉积 热氧化法制备了含有中间层的Sb掺杂钛基SnO2 电催化电极(Ti/SnO2),采用SEM、EDX以及 XRD 等检测方法对所制备电极的表面形貌、元素组成及结构进行分析,并以苯酚为目标有机物,研究所制备电极对有机污染物的电催化降解能力。研究结果表明所制备 Ti/SnO2 电极可在较短时间内将苯酚彻底降解,其较大的真实表面积以及电极中间层的存在是所制备电极性能提高的重要原因。阳极极化曲线扫描(LSV)的分析结果表明所制备的 Ti/SnO2电极具有较高的阳极析氧电位,有利于有机物的阳极氧化降解。     

钛基Co中间层SnO2电催化电极的制备及性能研究

为提高钛基二氧化锡电极的稳定性,设计并制备了含Co中间层的钛基二氧化锡电催化电极Ti/Co/SnO2,以苯酚为目标有机物,考察了所制备Ti/Co/SnO2电极电催化氧化降解苯酚的性能,并采用SEM、EDX以及XPS等检测方法分析了Ti/Co/SnO2电极表面的形貌、元素组成及元素化学态.研究结果表明,含有中间层的Ti/Co/SnO2电极其使用寿命较不含中间层的钛基二氧化锡电极Ti/SnO2大幅度提高,但其对苯酚的电催化降解活性有所下降,氧化还原电对Co2 /Co3 的存在是所制备Ti/Co/SnO2电极稳定性及电催化活性改变的主要原因.     

Fe掺杂钛基SnO2/Sb电催化电极的制备及表征

为了改进钛基SnO2/Sb电极的电催化性能,采用高温热氧化法制备了Fe掺杂钛基SnO2/Sb 电极.采用SEM、EDX以及XRD等方法对所制备电极的表面形貌、元素组成及结构进行分析,并以苯酚为目标有机物,研究了所制备电极对有机污染物的电催化降解能力.结果表明,适量Fe的掺杂有利于晶粒细化和导电性的提高;但过量Fe的掺杂可能导致SnO2晶格的混乱程度增大,甚至使晶格破坏,从而使电极性能降低;掺杂0.5?的SnO2/Sb电极对苯酚的降解效果优于未掺杂Fe的电极;电解3 h后,苯酚去除率和化学需氧量(COD)去除率分别达到100.0%和92.0%.     

含Mn中间层钛基二氧化锡电催化电极的性能

采用高温热氧化方法制备了含Mn中间层的钛基二氧化锡电催化电极Ti/Mn/SnO2.采用SEM、EDX以及XPS等检测方法对电极表面涂层的形貌、元素组成及元素化学态进行了分析,研究了所制备Ti/Mn/SnO2电极电催化氧化降解苯酚的性能.结果表明,Mn中间层的引入降低了电极对苯酚的电催化降解活性,使电极的使用稳定性大为提高.含Mn中间层的存在,可防止电化学反应过程中析出的氧向基体的扩散,离子对Mn2 /Mn4 与Sn2 /Sn4 的存在改变了SnO2电极表面催化剂的组成和结构,导致电极性能变化.     

改性SnO2电极的制备及电催化性能研究

为了研究3种掺Sb、掺Ru和掺Ru、Ce钛基SnO2电极的性能,以热分解法制备了改性钛基SnO2电极.利用扫描电镜和X射线衍射分析方法表征了电极的表面形貌和晶体结构,通过加速寿命实验考察电极的使用寿命,并以邻硝基苯酚为目标有机物,考察了电极的电催化性能.实验结果表明:Ru和Ce的掺杂减小了晶体颗粒的尺寸;Ti/Ru-Ce-SnO2电极的使用寿命远远高于Ti/Sb-SnO2电极;用Ti/Sb-SnO2电极电催化氧化降解ONP时,溶液中的COD去除率是最高的(80.3%),比Ti/Ru-Ce-SnO2电极的去除率(78%)略高;Ti/Sb-SnO2电极对ONP的去除速率是最快的,同时Ti/Ru-Ce-SnO2电极对ONP的去除速率与前者相比相差不大.因此,Ti/Ru-Ce-SnO2具有较高的电催化性能和高的使用寿命,综合分析认为Ti/Ru-Ce-SnO2电极具有更好的应用前景.     

表层稀土掺杂PbO_2电极及对苯酚电催化氧化性能研究

以钛电极为基体,用热分解法制备Sn-Sb中间层,电沉积方法制备稀土La掺杂PbO2电极,优化了制备改性PbO2电极的电沉积温度、电沉积时间及稀土掺杂量。以苯酚废水为目标有机物,借助于苯酚去除情况分析电极的电催化氧化能力;分析了电极结构与电催化特性之间的关系。采用SEM、EDX和XRD分析了制备电极的表面形貌、元素组成、晶体结构。实验结果表明:电沉积液温度50℃,电沉积2 h,稀土镧掺杂量4∶1的PbO2电极降解苯酚电催化性能有明显改善,其去除率达到90.9%。     

钕掺杂Ti／TiO2电极的制备并用于油田废水的降解实验研究

以Ti（OBu）4、二乙醇胺、C2H3OH、Nd（NO3）,为前驱体,制备稀土（Nd）掺杂TiO22溶胶,以钛电极为基体,用溶胶-凝胶法制备稀土（Nd）掺杂TiO2电极,优化了制备改性研O2电极的稀土掺杂量、热处理温度及热处理时间。以油田废水为目标有机物,借助于COD去除情况分析电极的电催化氧化能力;分析了电极结构与电催化特性之间的关系。采用SEM、EDX和XRD分析了制备电极的表面形貌、元素组成、晶体结构。掺杂Nd后电极的表面凹凸感变小,表面更为平滑、致密,几乎没有裂缝,这种均匀一致的高密度小碎片结构可能具有较大的表面粗糙度和比表面积,有利于催化反应。TiO2电极的晶体结构主要为锐钛矿型。稀土的掺入使得晶相所对应的衍射峰强度变弱且峰形宽化,这说明适量Nd的掺杂使涂层表面TiO2晶粒细化了。结果表明,掺杂Nd元素的电极,掺杂比（质量比）为Ti：Nd=100：1、热处理温度为540℃、热处理时间为60min时电极催化性能最好,此电极对目标有机物CODCr去除率达到81.6％,而不掺杂稀土元素的Ti／TiO2电极为阳极时COD-Cr去除率在同样时间内仅为67．7％,说明稀土的掺杂有利于电极催化性能的提高。     

Ce掺杂钛基二氧化锡电极的制备及电催化性能研究

采用高温热氧化法制备了稀土Ce掺杂SnO2/Sb电极,以SEM、EDX、XRD以及XPS等分析方法对所制备电极进行了形貌、组成及结构的表征,并根据Scherrer公式计算了电极表面SnO2的平均晶粒尺寸.结果显示,所制备电极涂层由纳米级的微晶SnO2构成,Ce的掺杂使Sb向电极表面富集,同时Ce本身也有向电极表面富集的趋势;Ce的掺杂影响了SnO2晶粒的成核过程,可能减少了晶格中的氧缺位.对苯酚的电化学氧化降解实验研究表明,Ce的掺杂降低了SnO2/Sb电极对苯酚降解中间产物的降解效率.     

改性PbO2 电极电催化降解水中硝基苯酚

为研究PbO2电极的性能,在酸性溶液中,以电沉积法制备了改性钛基PbO2电极,优化并确定了电极的制备工艺,并利用SEM对电极的表面形貌进行了检测.以硝基苯酚为目标有机物,考察了电极的电催化氧化性能.采用铋掺杂PbO2电极处理水中邻硝基苯酚、间硝基苯酚和对硝基苯酚,并对不同硝基苯酚的矿化过程以及降解动力学进行了比较.研究表明:改性PbO2电极的电催化性能优于传统的PbO2电极;邻硝基苯酚在本研究条件下更易被降解.     

Preparation and characterization of Ti/SnO(2)-Sb(2)O(3)-Nb(2)O(5)/PbO(2) thin film as electrode material for the degradation of phenol

In this work, a novel electrode of titanium substrate coated with mixed metal oxides of SnO(2), Sb(2)O(3), Nb(2)O(5) and PbO(2) was successfully prepared using thermal decomposition and electrodeposition. The surface morphology and the structure of the prepared thin film were characterized by scanning electronic microscopy (SEM) and X-ray diffraction (XRD), respectively. Experimental results showed that the structure of the prepared electrode might be described as a Ti/SnO(2)-Sb(2)O(3)-Nb(2)O(5)/PbO(2) thin film and its surface was mainly comprised pyramidal-shape beta-PbO(2) crystals. The modified electrode had higher oxygen evolution potential than that of other PbO(2) modified electrodes. Electrocatalytic oxidation of phenol in aqueous solution was studied to evaluate the potential applications of this electrode in environmental science. The phenol removal efficiency in an artificial wastewater containing 0.50g/L phenol could reach 78.6% at 20 degrees C and pH 7.0 with an applied electricity density of 20mA/cm(2) and treatment time of 120min. When 21.3g/L chloride was added to this wastewater, the removal efficiency could reach to 97.2%.     

Electrochemical treatment of paper mill wastewater using three-dimensional electrodes with Ti/Co/SnO2-Sb2O5 anode

The properties of the interlayer and outer layer of Ti/Co/SnO2-Sb2O5 electrode were studied, and the electrochemical behavior was examined as well. As a result of unsatisfactory treatment using Ti/Co/SnO2-Sb2O5 electrode, electrochemical disposal of paper mill wastewater employing three-dimensional electrodes, combining active carbon granules serving as packed bed particle electrodes, with Ti/Co/SnO2-Sb2O5 anode, was performed. The outcome demonstrates that efficient degradation was achieved. The residual dimensionless chemical oxygen demand (COD) concentration reached 0.137, and color removal 75% applying 167 mA cm(-2) current density at pH 11 and 15 g l(-1) NaCl. The instant current efficiency, energy cost, electrochemical oxidation index (EOI) and kinetic constant of the reaction were calculated. At the same time, the influence of pH and current density on COD abatement and decolorization was also investigated, respectively.     

Electrochemical treatment of anionic surfactants in synthetic wastewater with three-dimensional electrodes

The electrochemical oxidation of anionic surfactants (sodium dodecyl benzene sulfonate, DBS) contained in simulated wastewater treated by three-dimensional electrode system with combined modified kaolin served as packed bed particle electrodes and Ti/Co/SnO(2)-Sb(2)O(3) anode was studied, the chemical oxygen demand (COD) removal of pollutants in the solutions was also investigated. The results showed that the three-dimensional electrodes in combined process could effectively decompose anionic surfactants. The COD removal efficiency can reach 86%, much higher than that of Ti/Co/SnO(2)-Sb(2)O(3) electrodes used singly or modified kaolin employed singly (graphite as anode and cathode) on the same condition of pH 3 and 38.1 mA/cm(2) current density. The current efficiency and kinetic constant were calculated and energy consumption was studied. At the same time the influence of pH and current density on COD removal efficiency with combined three-dimensional electrodes was also investigated, respectively. The optimal initial pH value of degradation is 3 (acid condition), and a minor COD removal increase follows higher current density.     

Electro-catalytic degradation of phenol on several metal-oxide anodes

Three kinds of Ti-based multilayer metal-oxide electrode, including Ti/SnO(2)+Sb(2)O(3)/PbO(2), Ti/SnO(2)+Sb(2)O(3)/MnO(x) and Ti/SnO(2)+Sb(2)O(3)/RuO(2)+PbO(2) electrodes, were prepared by thermal decomposition, and SnO(2)+Sb(2)O(3) coatings were produced with a polymeric precursor method (PPM). The conversion of phenol was carried out with these electrodes as anodes under galvanostatic control. Samples during the electrolyses were characterized with UV-vis spectra and chromatography, and chemical oxygen demand (COD) and instantaneous current efficiency (ICE) for phenol degradation were also determined. The results show that phenol can be oxidized and degraded for all of the three anodes, and the oxidation reactions of phenol follow first-order kinetics, but there are considerable differences in the effectiveness and performance of electro-catalytic degradation. Phenol can be degraded relatively fast on the Ti/SnO(2)+Sb(2)O(3)/PbO(2) anode and the degradation rate of phenol is slower with the Ti/SnO(2)+Sb(2)O(3)/MnO(x) electrode, and the slowest with the Ti/SnO(2)+Sb(2)O(3)/RuO(2)+PbO(2) electrode, whose apparent rate constants are 2.49 x 10(-2), 1.42 x 10(-2) and 9.76 x 10(-3) min(-1), respectively. The rates of electro-catalytic degradation relate to oxygen evolution potential, and the higher the oxygen evolution potential, the better the performance of electro-catalytic degradation. The potential for oxygen evolution at the Ti/SnO(2)+Sb(2)O(3)/PbO(2) anode is highest, then Ti/SnO(2)+Sb(2)O(3)/MnO(x), following Ti/SnO(2)+Sb(2)O(3)/RuO(2)+PbO(2). The accelerated life tests at 60 degrees C and in 1.0 mol L(-1) aqueous H(2)SO(4) with an anodic current density of 4.0 Acm(-2) show that the service life is prolonged when the SnO(2)+Sb(2)O(3) interlayer coating are inserted between Ti substrate and active layers.     

焙烧温度对掺锑SnO2薄膜光电催化性能的影响

采用溶胶-凝胶法制备了掺锑二氧化锡薄膜电极,运用XRD、SEM、循环伏安等检测手段对薄膜电极进行了表征,并探讨了热处理温度对薄膜的元素组成、结构、物相、氧化能力的影响。以苯酚为目标降解有机物,研究了所制备的薄膜电极对有机物光电催化降解能力及矿化程度的影响。结果表明,焙烧温度对薄膜的微观结构、表面组成、导电能力及活性均有很大影响,不同温度焙烧制备的掺锑二氧化锡薄膜均为多晶结构的半导体;经一定温度焙烧后的电极表面具有不同程度的龟裂状裂纹,使电极表面积增大,活性点增多;当焙烧温度为450℃时,所制的掺锑二氧化锡薄膜电极电阻最小,氧化能力最强,且对目标有机物的降解效果最好。     

多元中间过渡层钛基氧化锰电极的寿命及电化学性能

采用热分解法制备了不同中间层的钛基氧化锰电极,利用SEM、XPS和XRD方法对电极进行了表征,应用加速寿命试验方法测试了电极在60℃、1.0mol/L H2SO4溶液中的预期使用寿命,同时测定了酸性溶液中该类电极的动力学参数(a、b、i0),运用双位垒模型讨论了电极的电化学性能。结果表明,具有RuO2+SnO2+MnO2+Sb2O4固溶体中间层的钛基氧化锰电极在高电流密度下(4A/cm2)的寿命可高达58h,电化学动力学表明该电极在酸性溶液中的析氧活化能较低,a值较小,i0值较大,是酸性溶液中较好的析氧电极材料。     

聚乙二醇改性钛基PbO_2电极的制备及性质研究

采用电沉积法制备不同浓度聚乙二醇(PEG)改性PbO2电极,通过SEM、XRD等对电极表面形貌和晶相结构进行表征,利用苯酚降解实验考察电极的电催化氧化特性,并进一步通过电化学阻抗谱(EIS)和线性极化扫描(VA)实验考察其电化学性质.SEM和XRD结果表明,PEG可以使电极表面颗粒明显趋于细化,提高β-PbO2的结晶纯度.电化学实验表明改性电极具有更好的电催化活性,更低的界面转移电阻和更高的析氧电位,PEG最佳掺杂浓度为6g/L.苯酚五次连续降解和加速寿命测试实验表明,优化电极具有良好的电催化稳定性,更长的使用寿命和更好的耐腐蚀性.     

钛基SnO2纳米涂层电催化电极的制备及性能研究

为提高Ti/SnO2电极的电催化性能,采用溶胶-凝胶法,并结合高温热处理工艺制备了钛基SnO2纳米涂层电催化电极.以苯酚为目标污染物,考察了所制备电极的电催化性能,并采用XRD、SEM、XPS等方法研究了制备的SnO2纳米涂层电极的表面形貌、晶粒粒径、元素组成和表面元素的化学环境等.研究结果表明:由于纳米涂层具有较大的比表面积,使得所制备电极的性能较非纳米涂层的钛基二氧化锡电极大为提高,完全降解等量苯酚所需时间减少了33.3%.电极表面主要是四方相金红石结构的SnO2晶体,粒径在10 nm以下.     

Ti/SnO_2 Sb_2O_3 MnO_2/PbO_2阳极的性能研究

制备了一种非贵金属阳极－Ｔｉ／ＳｎＯ２＋Ｓｂ２Ｏ３＋ＭｎＯ２／ＰｂＯ２,并用ＸＲＤ、ＳＥＭ进行了表征,计算出了电极的分形维数,测定了该电极在硫酸中的使用寿命和动力学参数,把该电极用于处理含酚废水和Ｐｂ电极进行对比．结果表明,节电３３％,转化率达９５％,是一种优良的电化学催化剂．     

不同组份PbO2-MnO2催化层钛基阳极的研究

本文用热分解方法制备了ＰｂＯ２－ＭｎＯ２混合金属氧化物阳极，对电极进行了ＥＤＳ、ＳＥＭ、ＸＲＤ研究，测定了电极在１ｍｏｌ／ＬＨ２ＳＯ４溶液中的使用寿命和动力学参数，结果表明：所制备电极具有优良的电催化活性和电化学稳定性。