Lead film electrode

To further reduce weight and improve energy density, several companies are developing thin lead film electrodes in a spiral-wound construction with glass fiber separators. Already on the market for cordless electric tools, this battery technology may eventually be used in electric vehicles. 

Tyszczuk BC, Korolczuk M (2007) Fast simultaneous adsorptive stripping voltammetric determinatiini of Ni (II) and Co (II) at lead film electrode plated on gold substrate. Electroanalysis 19 1539—1542... 

Korolczuk M, Tyszczuk K, Grabarczyk M (2005) Adsorptive stripping voltammetry of nickel and cobalt at in situ plated lead film electrode. Electrochem Commim 7 1185-1189... 

Bobrowski A, Kalcher K, Kurowska K (2009) Microscopic and electrochemical characterization of lead film electrode applied in adsOTptive stripping analysis. Electrochim Acta... 

Tyszczuk K, Korolczuk M (2010) Analysis of organic compounds using an in situ plated lead film electrode. Comb Chem High Throughput Screening 13 753-757... 

Stripping voltammetry involves the pre-concentration of the analyte species at the electrode surface prior to the voltannnetric scan. The pre-concentration step is carried out under fixed potential control for a predetennined time, where the species of interest is accumulated at the surface of the working electrode at a rate dependent on the applied potential. The detemiination step leads to a current peak, the height and area of which is proportional to the concentration of the accumulated species and hence to the concentration in the bulk solution. The stripping step can involve a variety of potential wavefomis, from linear-potential scan to differential pulse or square-wave scan. Different types of stripping voltaimnetries exist, all of which coimnonly use mercury electrodes (dropping mercury electrodes (DMEs) or mercury film electrodes) [7, 17]. 

Voltaic cells 64. 504 Voltammetry 7, 591 anodic stripping, 621 concentration step, 621 mercury drop electrode, 623 mercury film electrode, 623 peak breadth, 622 peak current, 622 peak potential, 622 purity of reagents, 624 voltammogram, 622 D. of lead in tap water, 625 Volume distribution coefficient 196 Volume of 1 g of water at various temperatures, (T) 87... 

Example 4-2 A rotating mercury film electrode (2 mm diameter) yielded a stripping peak current of 2.2 pA for a 1 x 10 8 M lead(II) solution following a 3 min deposition at —1.0 V with a 1600 rpm rotation. Calculate the peak current for a 2.5 x 10 8M lead(II) solution following a 2 min deposition with a 2500 rpm rotation. 

Garcia-Monco Carra et al. [296] have described a hybrid mercury film electrode for the voltammetric analysis of copper (and lead) in acidified seawater. Mercury plating conditions for preparing a consistently reproducible mercury film electrode on a glassy carbon substrate in acid media are evaluated. It is found that a hybrid electrode , i.e., one preplated with mercury and then replated with mercury in situ with the sample, gives very reproducible results in the analysis of copper in seawater. Consistently reproducible electrode performance allows for the calculation of a cell constant and prediction of the slopes of standard addition plots, useful parameters in the study of copper speciation in seawater. 

Acebal et al. [401] discussed the quantitative behaviour of lead (and copper) when voltammetric determinations are done at mercury film electrodes and hanging mercury drop electrodes. The samples were collected in polyethylene bottles and, generally, were not acidified immediately after collection. This might place some doubt on the results reported. 

Garcia-Monco Carra et al. [405] have discussed the use of a hybrid mercury film electrode for the voltammetric analysis of lead (and copper) in acidified seawater. 

Batley [780] examined the techniques available for the in situ electrodeposition of lead and cadmium in seawater. These included anodic scanning voltammetry at a glass carbon thin film electrode and the hanging drop mercury electrode in the presence of oxygen, and in situ electrodeposition on mercury-coated graphite tubes. 

Scarponi et al. [781] studied the influence of an unwashed membrane filter (Millpore type HA, 47 mm diameter) on the cadmium, lead, and copper concentrations of filtered seawater. Direct simultaneous determination of the metals was achieved at natural pH by linear-sweep anodic stripping voltammetry at a mercury film electrode. These workers recommended that at least 1 litre of seawater be passed through uncleaned filters before aliquots for analysis are taken the same filter can be reused several times, and only the first 50-100 ml of filtrate need be discarded. Samples could be stored in polyethylene containers at 4 °C for three months without contamination, but losses of lead and copper occurred after five months of storage. 

Batley [28] examined the techniques available for the in situ electrodeposition of lead and cadmium in estuary water. These included anodic stripping voltammetry at a glass carbon thin film electrode and the hanging drop mercury electrode in the presence of oxygen and in situ electrodeposition on mercury coated graphite tubes. Batley [28] found that in situ deposition of lead and cadmium on a mercury coated tube was the more versatile technique. The mercury film, deposited in the laboratory, is stable on the dried tubes which are used later for field electrodeposition. The deposited metals were then determined by electrothermal atomic absorption spectrometry, Hasle and Abdullah [29] used differential pulse anodic stripping voltammetry in speciation studies on dissolved copper, lead, and cadmium in coastal sea water. 

Electrodeposition of lead-tin alloy films is usually performed in the presence of peptone as an additive. Peptone is adsorbed on the metal surface during the electrodeposition process. The fractional surface coverage Q of the lead-tin electrode may be determined from the double-layer capacitance C measurements, and/or chronopotentiometric measurements. For a solution containing 9.0 g/L of tin and 13.0 g/L of lead, the following relationship between the concentration of peptone, the double-layer capacitance C, and the transition time At is observed (8). 

The disposable micro-glucose sensor consisted of thin-film electrodes positioned on a glass substrate and a small sample chamber (the iimer volume of which weis only 20 nL) was brought into contact with a silicon chip. Measmements were possible with as little as 1 pL of sample. The sensor sUncture is depicted in Fig. 3.18.E. The 10 x 20 mm silicon chip had a V-shaped groove that was 100-pm in wide, 70-pm deep and 5-mm long, in addition to two square sample inlets and five contact holes to connect lead wires to electrodes, all of which were formed by anisotropically etching the silicon. Four working electrodes that were 200 pm in width, and one counter-electrode that was 1.5-mm wide, were formed on a Pyrex substrate. The silicon chip and the Pyrex substrate were thermally bonded. 

Domenech A, Domenech-Carbo MT, Moya M, Gimeno JV, Bosch F (2000) Voltammetric identification of lead (11) and (IV) in mediaeval glazes in abrasion-modified carbon paste and polymer film electrodes. Apphcation to the study of alterations in archaelogical ceramic. Electroanalysis 12 120-127. 

Bismuth-film electrodes (BiFEs), consisting of a thin bismuth-film deposited on a suitable substrate, have been shown to offer comparable performance to MFEs in ASY heavy metals determination [17]. The remarkable stripping performance of BiFE can be due to the binary and multi-component fusing alloys formation of bismuth with metals like lead and cadmium [18]. Besides the attractive characteristics of BiFE, the low toxicity of bismuth makes it an alternative material to mercury in terms of trace-metal determination. Various substrates for bismuth-film formation are reported. Bismuth film was prepared by electrodeposition onto the micro disc by applying an in situ electroplating procedure [19]. Bismuth deposition onto gold [20], carbon paste [21], or glassy carbon [22-24] electrodes have been reported to display an... 

Capelo, S., Mota, A.M. and Gongalves, M.L.S. (1995) Complexation of lead with humic matter by stripping voltammetry. Prevention of adsorption with Nafion-coated mercury film electrode. Electroanalysis, 7, 563-568. 

---