海洋低频电场探测电极性能表征

为探测海洋环境中的低频电场，制备了固态Ag／AcCl电极，通过对电极稳定性、灵敏度及其对已知电场信号响应特性的考察，探讨了其用于海水环境中电场传感器探测电极的可行性，并用电化学交流阻抗的方法研究了不同频率范围时电极的界面反应特性。结果表明，在海水环境中，Ag／AcCl电极稳定性好，灵敏度高，频率响应特性好，能够较准确地探测海水中一定频率范围的交流电场信号，可作为海洋环境中电场传感器的探测电极。受电极界面反应影响，电极在探测信号时对应着一个最佳工作频率范围。     

Development of Zr/ZrO<Subscript>2</Subscript> high temperature and high pressure sensors for <Emphasis Type="Italic">in-situ</Emphasis> measuring chemical parameters of deep-sea water

In order to in situ measure chemical parameters of deep-sea water and hydrothermal fluids at midocean ridge(MOR), it is necessary to use high temperature and high pressure chemical sensors.Developing new sensors is essential to measure in-situ pH and other chemical parameters(dissolved H2, dissolved H2S) of deep-sea water and hydrothermal fluids in a wide temperature range(2℃―400℃) at MOR vents.The YSZ(Yttria Stabilized Zirconia, 9%Y2O3) ceramic-based(HgO/Hg) chemical sensors possess excellent electrochemic...     

一种全固态pH传感器的研制

研制了一种以石墨棒为基体在其上涂覆一层熔融锑-氧化锑为工作电极,固态Ag/AgCl电极为参比电极的全固态pH传感器。通过对不同pH的溶液进行电位测定,得出该电极在pH1.4～7.8的范围内,电位-pH曲线响应斜率为57.6,相关系数R2=0.999 6。详细地研究了该电极的各种性能指标,并将其用于实际样品的测定。同时与目前市场上购得的商用在线锑电极做了比较,该电极表现出较好的重现性,稳定性,准确性。电极制备过程中对熔融的锑粉采用了恒温处理,生成大量氧化锑,使得该锑电极的各种性能得到很大改善。     

An improved sensitivity non-enzymatic ascorbic acid sensor based on a Ag2O nanowire modified Ag electrode

In this paper, the Ag2O nanowires had been prepared and applied for the fabrication of ascorbic acid sensors with high enhanced sensitivity by using self-assembly technology. The structures and morphologies of Ag2O nanowires were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The direct electrocatalytic oxidation of ascorbic acid in alkaline medium at Ag2O nanowires modified electrodes had been investigated in detail and the condition for determination of ascorbic acid was optimized, such as support-electrolyte, pH and scan speed. The oxidation peak current changed linearly with the concentration of ascorbic acid over the range from 2.0×10-8 mol/L to 1.0 mmol/L, and the detection limit can reach 1.0×10-8mol/L. Compared to a bare Ag electrode, a substantial decrease in the overvoltage of the ascorbic acid oxidation was observed at the Ag nanowires electrodes with oxidation starting at ca. 0.7V vs. Ag/AgCl (saturated KCl). The Ag2O nanowires modified electrode allows highly sensitive, low working potential, stable, and fast amperometric sensing of ascorbic acid, thus is promising for the future development of non-enzymatic ascorbic acid sensors.     

Effect of sulphate-reducing bacteria on the electrochemical impedance spectroscopy characteristics of 1Cr18Ni9Ti

The electrochemical characteristics of 1Cr18Ni9Ti in sulphate-reducing bacteria (SRB) solutions and the biofilm of SRB on the surface of the 1Cr18Ni9Ti electrode were studied by electrochemical, microbiological, and surface analysis methods. Electro- chemical impedance spectroscopy (EIS) of 1Cr18Ni9Ti was measured in the solutions with and without SRB at the culture time of 2, 4, 8 d, respectively. The measurement used two test methods, the nonimmersion electrode method and the immersion electrode method. It was found that the polarization resistance (Rp) of 1Cr18Ni9Ti in the solutions without SRB is the greatest for each test method. When using the nonimmersion electrode method, Rp shifts negatively at first and then positively, and the time constant is only one. Although using the immersion electrode method, the Rp shifts positively at first and then negatively, and the time constant also changes when the biofilm forms. The biofilm observed through SEM is with pores. It was demonstrated that SRB has acceler- ated corrosion action on 1Cr18Ni9Ti. The protection effect of the biofilm on the electrode depends on the compact degree of the film.     

一种新型的钙离子选择电极的研制

本文介绍了一种新型钙离子选择电极,其结构是在离子敏场效应晶体管的栅上用含有活性物质的PVC膜覆盖。实验数据证明,钙离子敏场效应晶体管对Ca~( )离子的响应服从能斯特方程式。这种器件的特点是响应快,灵敏度高,对钙离子的平均响应斜率接近于25mV/PCa。本文还讨论了敏感膜机理。但是这种敏感器件的稳定性和重复性有待改善。     

Fabrication of ferrocenyl glutathione modified electrode and its application for detection of cadmium ions

l＇-cysteaminecarbonyl-1-glutathionecarbonyl-ferrocene （Fc-GSH） was synthesized from ferrocene dicarboxylic acid and reduced glutathione （GSH） with 4 steps. IR and 1^H-NMR were used to characterize the products. Then Fc-GSH was immobilized on the surface of gold electrode. Cyclic votammetry （CV） was adopted to investigate the electrochemical properties of this Fc-GSH modified electrode in the absence and presence of Cd^2＋ aqueous solutions. The peak oxidation potential （Ea） and reduction potential （Ec） of Fc-GSH modified electrode were observed at Ea= 0.74 V and Ec= 0.64 V （vs Ag/AgCl） before the accumulation of Cd^2＋. This redox process is a monoelectron chemical reaction. The anodic shift is about 80 mV in the presence of 20 nmol/L of Cd^2＋ aqueous solution. Moreover, this shift is in proportion to the concentration of Cd^2＋ when the concentration of Cd^2＋ is lower than 20 nmol/L. So the modified electrode can be used as probes to detect cadmium ions with the limit of 0.1 nmol/L by cyclic voltammetry.     

碳纳米管/TiO2电极光电催化测定耐兰方法探讨

自合成二氧化钛-碳纳米管（TiO2一CNT）复合催化剂，用Nafion溶液把CNT—TiO2固定到玻碳电极上制成CNT—TiO2／GC修饰电极，以耐兰染料为测定对象，进行光电化学响应研究．结果表明，在pH7．2的磷酸盐缓冲液中，示差脉冲伏安法（DPV）测定，分散兰1于-0．4V（vs Ag／AgCl）处产生良好的阴极还原峰，电极对耐兰染料的吸附过程符合Langmuir吸附，其光电响应值高于碳糊／TiO2电极．高光电响应意味着复合材料制成电极后，对有机染料废水的检测限更低，灵敏度更高。     

磷酸银光催化降解嗪草酮的动力学研究

采用沉淀法和光照还原沉淀法分别制备了Ag_3PO_4和Ag/AgCl/Ag_3PO_4两种可见光光催化剂,在可见光照射条件下,分别考察了其对水溶液中嗪草酮的降解动力学过程,并比较了二者的光催化活性差异以及稳定性.研究表明:嗪草酮的光催化降解过程均符合表观一级反应动力学,Ag/AgCl/Ag_3PO_4的催化活性和稳定性明显优于Ag_3PO_4,剂量为200 mg/L时,20 min内对嗪草酮的降解率达99%以上,循环使用4次后,降解率仍维持在88%以上.     

血红蛋白固定在Ti0.865O2纳米片层间的直接电化学和电催化

通过对层状纤铁矿型钛酸锂钾进行剥离,可以制备得到Ti0．865O2纳米片溶胶。将Ti0．865O2纳米片作为载体固定血红蛋白（Hb）,制备得到Hb/Ti0．865O2/纳米片修饰的热解石墨（PG）电极。在Ti0．865O2纳米片层间,Hb能实现与电极的直接电子转移。在pH值为5．6的磷酸盐缓冲溶液中,该修饰电极的循环伏安曲线上显示出一对可逆的氧化还原峰,式电位为-230mV（vs．Ag/AgCl）。该修饰电极对H2O2有良好的电催化响应,线性响应范围为50μM到2．2mM,灵敏度为10μA．mM^-1．cm^-2。     

The adsorbing effect of calcined layered double hydroxide for chloride ions in simulated concrete pore solutions

The adsorbing effect of calcined layered double hydroxide （CLDH） for chloride ions in simulated concrete pore （SCP） solutions was investigated with the potentiodynamic polarization method, impedance measurement, ion selective electrode analysis and XRD. CLDH could effectively adsorb Cl^- and increase pH value in SCP solutions containing NaCl. The chloride to hydroxyl ions ratio （[C1^-]/[OH^-]） of the solution greatly decreased by CLDH treatment. In CLDH treated SCP solution with CI-, the pitting potential of carbon steel notably increased, and the surface impedance was much higher, indicating strengthened passivation. The process of CLDH adsorbing chloride ions from SCP solutions was accompanied with the reconstruction of the layered structure.     

纳米TiO2管电化学生物传感器用于测定水体中微囊藻毒素

制作了辣根过氧化物酶和溶胶-凝胶结合Nafion-TiO2修饰石墨电化学传感器,用示差脉冲伏安法研究了该修饰电极的电化学性质,并优化了微囊藻毒素-LR(MC-LR)的测定条件.结果表明,在pH=6.5柠檬酸-NaOH-HCl缓冲溶液中,采用该修饰电极示差脉冲伏安法测定MC-LR,质量浓度在10-5～1μg/L范围内呈良好的线性关系,脉冲伏安法测定微囊藻毒素线性方程为100Δi=0.142 2logC+0.799 7,相关系数为0.995 0,最低检测限达10-6μg/L.电极的重现性及稳定性较好,连续测定10次,相对标准偏差为2.5%;4℃下储存28d后示差脉冲信号无明显变化;应用于饮用水中MC-LR的测定,样品的回收率为99.3%～102.9%.该传感器灵敏度高、稳定性好.     

Al/Pb-WC-ZrO2-Ag和Al/Pb-WC-ZrO2-CeO2 复合电极材料的性能研究

研究了Ag固体微粒对Al／Pb WC ZrO2 Ag复合电极材料电化学性能的影响、结果表明，银粉的质量浓度为3～4g／L时制得的Al／Pb WC ZrO2 Ag复合电极材料综合性能较好．研究Ce02固体微粒对Al／Pb WC ZrO2 CeO2复合电极材料电化学性能的影响，结果表明，当Ce02的质量浓度为10～20g／L时制得的A1／PbWCZr02Ce02复合电极材料相对较好．     

Ag修饰La0.8Sr0.2CoO3空气电极电催化性能

采用溶胶-凝胶法合成了钙钛矿型La0.8Sr0.2CoO3复合氧化物,并选用Ag对其进行修饰,获得Ag/La0.8Sr0.2CoO3纳米粉体,利用XRD、XPS方法对催化剂的结构与组成进行表征;然后将该粉体作为催化材料制备出空气电极,在碱性介质中,通过测量空气电极的稳态极化曲线和交流阻抗谱,考察Ag含量对催化剂的电催化活性的影响.研究发现,Ag的加入增强了La0.8Sr0.2CoO3复合氧化物的导电性,并对电极材料的催化活性起到一定的促进作用;当Ag的质量分数为8%时,Ag/La0.8Sr0.2CoO3氧化物电极材料催化活性较高.     

葡萄糖在纳米多孔Ir/IrO_x电极上的电催化氧化

主要研究纳米多孔Ir/IrOx电极的制备及电极对葡萄糖的检测.在150μm的铱电极上采用高电位氧化和低电位还原的方法成功的制备了纳米多孔Ir/IrOx电极,并对其进行表征.同时,研究了纳米多孔Ir/IrOx电极对葡萄糖的直接氧化,由此得出的结果是在pH为7.6的PBS溶液中,电位0.7 V的条件下电极对葡萄糖有较快较灵敏的响应,响应电流与葡萄糖浓度在2～22 mmol/L的范围内成正比,检测限为28.1μmol/L.     

高氮含量多孔碳的制备、热处理及氧还原性能

采用快速高温碳化法成功制备了具有海绵结构、氮原子摩尔分数高达7.5%的氮掺杂多孔碳材料（N-PC）,然后对其进行惰性氛围高温脱氮处理,获得氮原子摩尔分数为2.5%、起始电位-44 mV、半峰电位-134 mV、极限电流密度-4.5 mA·cm^-2的样品。分别用场发射扫描电子显微镜、X射线光电子能谱和Raman光谱对N-PC材料进行了表征。采用伏安法测定了材料在O₂饱和0.1 mol/L KOH电解液中的氧还原反应（ORR）性能。结果发现,高吡啶氮、吡咯氮摩尔分数的多孔碳材料不具备优异的氧还原性能,而脱氮后的多孔碳材料因有较多的结构缺陷,暴露出了更多的活性位点,表现出较好的电化学性能。N-PC具有与Pt/C催化剂相近的电催化性能,而且具有比Pt/C催化剂更高的耐甲醇能力和更好的稳定性。因此,N-PC可以作为铂催化剂在ORR领域的一个非常突出的替代选择。     

银纳米线的制备及其对电化学发光催化研究

采用水热法,在反应体系中加入微量的CuCl2作为去氧剂,以AgNO3为前驱物,聚乙烯吡咯烷酮(PVP)为稳定剂和结构导向剂,乙二醇为还原剂和溶剂制备银纳米线.研究了反应温度、反应时间及CuCl2浓度对产物微观形貌的影响.通过X-射线衍射(XRD)、扫描电子显微镜(SEM)等检测手段表征了其结构和性能.同时,将所制得的银纳米线作为联吡啶钌[Ru(bpy)2+3]电化学发光(ECL)的工作电极对其催化机理进行研究.结果表明:在反应温度为165℃、反应时间为1h、CuCl2浓度为4 mmol/L时制备出了具有面心立方结构的,长度为13 μm,长径比约为75的银纳米线;与普通银丝电极相比,由于具有较高的比表面积和较独特的催化特性,银纳米线电极更适合作为Ru(bpy)2+3 ECL的工作电极.     

三维和二维电极法催化降解苯酚废水

目的比较三维电极法与二维电极法对苯酚废水的处理效果．方法采用自制三维电极和二维电极反应器,以苯酚水样为处理对象,通过试验分析两种方法中各因素对苯酚废水处理效果的影响．结果在相同条件下,三维电极反应器对苯酚的去除率比二维电极反应器对苯酚的去除率高10％以上,对pH值的要求低于二维电极,可以处理质量浓度相对较高的苯酚废水,反应电压和电解时间、电解质投加量等因素均低于二维电极法．结论三维电极法极大地节约了处理成本,处理效果优于二雏电极法．     

Kinetics of CO2 reduction in KOH/methanol electrolyte on Pb electrode

As natural oil reserves become depleted, attentionwill increasingly focus on alternative energy sources.The energy and raw materials for this are currently de-rived from the burning of coal, with the accompanyingrelease of CO2as a by-product[1]. CO2causes…     

天然矿泉水脱钠的研究——硅胶为载体浸渍锑酸为脱钠剂

提出了以硅胶为载体将五价锑酸浸渍在活化硅胶中作为交换柱滤料,以除去矿泉水中钠离子,脱钠率可达99％以上,脱钠剂可再生,再生液为1mol·L~(-1)HNO_3+1mol·L~(-1)NH_4NO_3,钠离子含量的测定方法采用离子选择电极Rittner和Ma法,结果表明:此方法简便、可靠,结果满意,值得推广。