用于混凝土中钢筋腐蚀监测的固态Ag/AgCl参比电极的制作及其性能

为了制备可用于混凝土中钢筋腐蚀监测的参比电极,先在三电极体系下采用恒电流阳极氧化法获取Ag/Ag Cl探针,再通过凝胶电解质封装制备了固态Ag/Ag Cl参比电极。将其用于碱性混凝土孔隙液中,研究了其Nernst响应特性和电位稳定性,并探讨了其抗各种环境因素(p H值、SO2-4、温度、电化学极化)干扰的能力。结果表明:固态Ag/Ag Cl参比电极具有良好的Nernst响应;当p H值小于12时,p H值对参比电极电位影响较小,当p H值大于12时p H值每增加1,电极电位下降约50 m V;电极的温度响应特性与抗SO2-4干扰和抗极化能力较好,适用于混凝土中钢筋腐蚀的监测。     

电解型Ag/AgCl参比探头的制备及性能研究

通过电解法制备了Ag/AgCl参比探头,考察了其在0.1 mol/L KCl和人造海水中的电极电位稳定性,并用金相显微镜观察了电极的形貌.针对电解型Ag/AgCl电极寿命有限的特点,自制了盐桥,并研究了电极性能.结果表明,电解电流过大容易造成银丝过度氧化,AgCl膜层在银丝表面分布不均匀,且附着力低下,电极性能下降.电解电流适中时,Ag/AgCl电极电位稳定性、准确性良好,且通过自制盐桥,电极的寿命明显延长.     

全固体Ag/AgCl电极的制备工艺研究

探讨了制备全固体Ag/AgCl电极所用的AgCl前驱粉体的工艺技术,对其进行了形貌和物相分析,并对工艺改进后制备电极的短期稳定性、电化学噪声水平进行了测试.结果表明,以AgNO3和NaCl为原料,利用乙醇作为助磨剂,球磨8h后,利用冷冻干燥法所制备的AgCl粉体分散性极好,大小均匀,在490℃下烧结后所制备的Ag/AgCl复合电极一致性好,同种电极之间的极差电位约为0.006mV.该电极具有良好的短期稳定性能,电极电位波动量不超过0.080mV/24h,电极电压噪声密度在1Hz处可降低至8.34nV/Hz1/2.     

二氧化锰参比电极的制作及其性能评定

参比电极对检测钢筋混凝土中钢筋的电位至关重要,而应用于混凝土中的进口高性能参比电极的成本极高.为此,仿制了一种二氧化锰参比电极,并用常规电化学方法对其电位稳定性能进行测试.结果表明:在17.8 ℃、pH值为13.98的模拟孔隙液[0 6 mol/L KOH 0.2 mol/L NaOH 饱和Ca(OH)2]中,二氧化锰电极的电位稳定在60～80 mV,单个电极的电位波动不超过±5 mV; 10 μA电流阴、阳极极化时,电位波动不超过10 mV;温度变化时,电极电位变化小,可恢复.仿制的电极与国外商业二氧化锰参比电极的性能基本接近.     

混凝土腐蚀监测用参比电极制作及电化学性能研究

参比电极对监测混凝土中钢筋的电位至关重要。使用凝胶作为电极内部电解质、水泥浆作为渗透层,制成Ag/AgCl凝胶参比电极。在混凝土模拟液中测试了电极电位的稳定性、电极的温度系数以及氯离子含量对电位的影响,通过动电位和恒电流极化测试了电极的抗极化性能,并在混凝土中进一步研究了电极电位的时变特性。结果表明,电极电位有良好的稳定性和可靠性,电极温度系数较小,氯离子含量对电极电位的影响可以忽略,电极抗极化性能优良。研制的电极可用于实时监测混凝土内部钢筋的腐蚀电位,为钢筋混凝土构件寿命预测提供参考。     

长寿命硫酸铜参比电极的研制及性能评价

一、前言在电化学领域中,测量金属构筑物的电极电位必须要用参比电极。在电化学保护中,参比电极既可用来测量被保护构筑物的电位,又可作为恒电位仪自动控制的讯号源。近一个时期,国内外都在寻找埋地型长寿命电极。1983年南京土壤所和华北油田设计院联合开发的全固态长效硫酸铜参比电极,目前已在各油田普遍使用,寿命达1年;1983年核工业部第五研究所研制了固体Ag/AgCl电极,而后又开发了Cu/CuSO_4多盐桥式电极,前者在化工介质中获得了推广;1982年华东输油局开展了石墨接界硫酸铜电极的研制;由东北输油局和中科院金属腐蚀与防护研究     

涂敷法制备Ag-AgCl参比电极及其性能

目前制备Ag-AgCl参比电极的方法复杂,电极性能也不稳定。首次用涂敷法制备了Ag-AgCl参比电极：分别以水溶性的丙烯酸乳液和乙烯-聚醋酸乙烯乳液作为粘合剂,将AgCl微粒粘结在Ag电极表面制成Ag-AgCl参比电极。结果表明：2种Ag-AgCl参比电极的稳定性良好,使用寿命较长,均能满足使用要求;其中,以乙烯-聚醋...     

Ag/AgCl/MoO_3复合材料的制备及其光催化性能

利用水热合成法合成六方相晶体结构的MoO3微晶,采用沉淀-沉积法和光致还原法将Ag/AgCl纳米颗粒沉积于MoO3微晶上,从而制得新型的Ag/AgCl/MoO3异质结光催化剂。通过包括紫外-可见漫反射吸收光谱(UV-Vis-DRS)等方法在内的各种测试技术对催化剂结构、形貌等进行表征。并以苯并噻吩(BT)为目标硫化物,研究在可见光下催化剂用量、氧化剂用量、前驱体浓度及反应时间对BT的氧化脱除的影响。研究结果表明:Ag/AgCl/MoO3异质结在催化剂用量为1.5g/L,氧化剂用量O∶S=4,前驱体Mo(VI)浓度为0.07mol/L,可见光照射2.5h后,光催化氧化脱硫活性达92%。     

Ag/AgCl纳米枝状结构的制备及其光催化性能研究

采用离子液体法,以离子液体(DESs)为溶剂,柠檬酸三钠为还原剂,氯金酸为晶种,硝酸银为银源,制备了Ag/AgCl纳米枝状结构。利用SEM、XRD、EDS对样品的形貌、成分、结构进行了表征分析,并测试了样品的光催化性能。结果表明,当反应温度为160℃,反应时间为24h时,可获得完整的Ag/AgCl纳米枝状结构;枝状结构的形成是基于AgCl在还原剂作用下不断向Ag转换过程的结果;产物具有较好的光催化效果,并且随着反应时间的延长,产物的光催化性能减弱。     

Ni-YSZ阳极添加Ag对固体氧化物燃料电池性能影响

为研究在Ni-YSZ阳极添加银对固体氧化物燃料电池(SOFC)性能的影响,采用化学镀银法在电池阳极镀银,在750℃分别以氢气和甲烷为燃料气,测试电池的电化学性能,并用扫描电子显微镜对测试前后的阳极进行表征。结果表明,电池在阳极镀银后,极化电阻减小,放电性能和抗积碳能力提高。化学镀银法镀银10min的电池在750℃以氢气为燃料气时,最大功率密度为511.7 mW·cm-2,比未镀银电池增加31.8%,以甲烷为燃料气时,以200mA·cm-2恒流稳定运行24h后,有少量积碳,相比恒流前最大功率密度降低0.8%。     

Fabrication of a planar-form screen-printed solid electrolyte modified Ag/AgCl reference electrode for application in a potentiometric biosensor

This study features the fabrication of a planar-form, solid electrolyte modified, (PSEM) Ag/AgCl reference electrode using a screen-printing method. The PSEM Ag/AgCl reference electrode uses agar gel as the inner electrolyte and chloroprene rubber for the liquid junction and insulator. These common low-cost materials and the simple fabrication processes involved render the proposed reference electrode an ideal candidate for cost-efficient mass production. It is shown that the developed reference electrode is insensitive to most of the physiologically important ionic species, including Na+, K+, Li+, Ca2+, NH4+, and Cl-, under continuous measurement conditions. Moreover, as with conventional commercial reference electrodes, the proposed reference electrode exhibits a reversible response, which is maintained until the agar gel dries out. The PSEM Ag/AgCl reference electrode is integrated with an iridium oxide modified Pt-based pH indicator electrode to form a chip-type pH biosensor. The performance of this biosensor is consistent with that obtained from a pH meter based on a macroscopic commercial Ag/AgCl reference electrode. The experimental results confirm that the proposed biosensor is capable of providing precise pH measurements of various real samples. Accordingly, the PSEM Ag/AgCl reference electrode presented in this study provides a viable alternative to the macroscopic Ag/AgCl reference electrode used in many conventional chip-based pH sensors.     

Application of a new Cl-plasma-treated Ag/AgCl reference electrode to micromachined glucose sensor

Micromachined glucose sensors were fabricated and integrated with the plasma-treated Ag/AgCl reference electrodes for the first time. The surface of the Cl-plasma exposed AgCl layers was of granule-shaped morphology and showed the favorable long-term stability with a 13-mV potential drift after 5 h over a commercial liquid-junction Ag/AgCl reference electrode in phosphate buffered saline. The fabricated devices showed a typical behavior of an amperometric glucose sensor and a successful operation as a three-electrode system. Due to the integrability of the reference electrode and the use of low-temperature steps only, the new micromachined process can allow easy mass production of the device and the monolithic integration of signal processing circuitry in the future.     

Diffusion-controlled size-selective chloride ion sensing in the presence of bromide ion using a thin, nanoporous, plasma-polymerized coating on an Ag/AgCl electrode

We have developed a diffusion-controlled size-selective method for sensing chloride ion in the presence of bromide ion, based on a thin, nanoporous, plasma-polymerized coating of hexamethyldisiloxane on an Ag/AgCl electrode. Sub-nanometer-sized pores responsible for a highly cross-linked polymer network in the plasma-polymerized coating allowed diffusion-controlled permeation of chloride ion while blocking the larger bromide ion. An electrode coating of thickness greater than 70 nm enabled chloride detection in the concentration range 1-10 mM in the presence of 0.63 mM bromide ion. Advantages of this approach are: (1) simple design compared with ionophore-based strategies and (2) compatibility with microfabrication and mass production processes.     

泵氧型铈锆固溶体参比氧传感器的制备

传统片式浓差型氧传感器存在陶瓷成型工艺复杂、成本高等问题。为解决此类问题,利用铈锆固溶体储氧材料的储氧特性,将其作为固体氧参比材料代替空气参比,研制铈锆固溶体参比氧传感器,探讨不同化学组成和厚度的CeO2-ZrO2固溶体对传感器氧敏信号的影响。并通过增加泵氧单元以抑制氧敏信号衰减,解决了实际使用中因铈锆固溶体中氧消耗而导致的氧传感器输出信号衰减问题,可满足车用氧传感器的正常工作需要。     

等离子喷涂制造固体氧化物燃料电池三合一电极

采用大气等离子喷涂法在阳极支撑上制备了电解质与阴极.利用X射线衍射分析了阴极与阳极喷涂前后的成分和相结构,用扫描电镜观察了SOFC( solid oxide fuel cell)三合一电极的截面形貌以及阳极、电解质与阴极的表面形貌.结果表明:喷涂前后阴极的化学成份未发生改变,阴极为单斜相、钙钛矿型的(La0.8Sr0.2MnO3)LSM;阳极在喷涂前为Ni/YSZ(Y2O3稳定ZrO2),在喷涂后Ni被氧化成NiO.由阳极、电解质与阴极构成的三合一电极界面不明显,其中电解质致密,阳极与阴极有一定孔隙.     

New class of Ag/AgCl electrodes based on hydrophobic ionic liquid saturated with AgCl

A new type of Ag/AgCl electrodes based on a hydrophobic ionic liquid has been proposed. The electrode consists of a Ag/AgCl electrode immersed in or coated with a AgCl-saturated ionic liquid, 1-methyl-3-octylimidazolium bis(trifluoromethylsulfonyl)imide ([C(8)mim+][C(1)C(1)N-]), instead of the internal aqueous solution. The [C(8)mim+][C(1)C(1)N-] phase plays dual roles, that is, as a medium dissolving AgCl and an ionic-liquid-type salt bridge upon contact with an aqueous solution. The gelation of the [C(8)mim+][C(1)C(1)N-] phase allows us to prepare coated-wire-type solid-state reference electrodes with a well-defined thermodynamic basis for the electrode potential. Both gelled and nongelled types show stable electrode potentials against the change in the concentration of KCl between 0.05 mmol dm(-3) and 2 mol dm(-3). This new class of reference electrodes opens the way for a variety of miniaturized and solid-state reference electrodes.     

Ag/AgCl氯离子传感器在混凝土中的应用

尝试将试验室制作的Ag/AgCl氯离子传感器用于混凝土中测试,验证该传感器应用于混凝土结构中的可行性。测试了传感器在混凝土试件中的长期稳定性,建立了传感器在混凝土中的线性响应方程,并通过加速氯离子渗透的方式对建立的线性方程进行了验证。试验结果表明,传感器在混凝土试件中可以长期稳定有效地工作,85d电位波动25mV,传感器在氯离子掺量相同的试件中电位响应一致性良好;通过建立的线性方程计算得到的电位响应值与实测电位响应值符合得很好,所建立的方程与试件水胶比水平无关,与氯离子的引入方式无关,是适用于混凝土结构的比较准确的线性方程。通过该方程的建立即可实现使用该传感器监测混凝土结构中的氯离子分布,达到钢筋锈蚀提前预警的目的。     

ZrO2高温固态电极交换电流密度的研究

利用对称电池Ｍ，ＭｘＯｙ│ＺｒＯ２（ＭｇＯ）│Ｍ，ＭｘＯｙ在高温下对固态参比电极的极化特征进行了研究。实验研究表明，在本实验的条件下，极化电流与超电势之间为线性关系。Ｍｏ／ＭｏＯ２参比电极的交换电析的交流密度远大于Ｃｒ／Ｃｒ２Ｏ３、Ｎｉ／Ｎｉ／ＮｉＯ、Ｃｏ／ＣｏＯ参比电极的交换电流密度。电极交换电流密度随参比电极中金属含量的啬及温度的升高而增大。根据实验测试得到了电极反应的活化能。     

Organic photovoltaic cells fabricated on a SnOx/Ag/SnOx multilayer transparent conducting electrode

Transparent conducting multilayer structured electrode of a few nm Ag layer embedded in tin oxide thin film SnO_x/Ag/SnO_x was fabricated on a glass by RF magnetron sputtering at room temperature. The multilayer of the SnO_x(40 nm)/Ag(11 nm)/SnO_x(40 nm) electrode shows the maximum optical transmittance of 87.3% at 550 nm and a quite low electrical resistivity of 6.5 × 10^− 5 Ω cm, and the corresponding figure of merit (T¹⁰/R_S) is equivalent to 3.6 × 10^− 2 Ω^− 1. A normal organic photovoltaic (OPV) structure of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)/polythiophene:phenyl-C60-butyric acid methyl ester/Al was fabricated on glass/SnO_x/Ag/SnO_x to examine the compatibility of OPV as a transparent conducting electrode. Measured characteristic values of open circuit voltage of 0.62 V, saturation current of 8.11 mA/cm² and fill factor of 0.54 are analogous to 0.63 V, 8.37 mA/cm² and 0.58 of OPV on commercial glass/indium tin oxide (ITO) respectively. A resultant power conversion efficiency of 2.7% is also very comparable with the 3.09% of the same OPV structure on the commercial ITO glass as a reference, and which reveals that SnO_x/Ag/SnO_x can be appropriate to OPV solar cells as a sound transparent conducting electrode.