Lead films

The second set of experiments was carried out in 1929 by Paneth. The decomposition of tetramethyllead was carried out in such a way that the decomposition products were carried by a flow of inert gas over a film of lead metal. The lead was observed to disappear with re-formation of tetramethyllead. The conclusion was reached that methyl radicals must exist long enough in the gas phase to be transported from the point of decomposition to the lead film, where they were reconverted to tetramethyllead. 

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. 

Fig. 1.19. Metal insuiator-metal tunneling junction. The junction is made through the following steps, (a) The substrate, a glass slide with indium contacts, (b) An aluminum strip is vacuum deposited, (c) The aluminum strip is heated in air to form a very thin (—30 A) aluminum oxide (AI2O3). (d) A lead film is deposited across the aluminum strip, forming an Al-Al203-Pb sandwich. (After Giaever and Megerle, 1961.)...

Good adhesion of electrodeposited lead to copper substrates has been reported [295-299]. Voltammetric curves of Pb deposition on Cu in alkaline solution with glycerol [299] are characterized by two peaks, corresponding to film and mass transfer-controlled bulk deposition, respectively. SEM results have not confirmed the propagation of dendrites, even at very low deposition potentials. Lead film deposition occurs prior to lead bulk... 

Todd, M.J., Lead-Film Lubrication in Air and Vacuum, Proc. 1st. Europ. Space Trib. Symp., Frascati, Italy, ESA SP-111, p. 225, (Oct. 1975). 

We may mention here a B subgroup hydride which does not fall into any of our classes (i)-(iii), namely, PbHo. 19. This is formed by the action of atomic hydrogen at 0°C on an evaporated lead film, and apparently possesses considerable stability/ ... 

This is red lead monoxide, used as in inorganic accelerator for the curing of soft natural rubber lining in an autoclave. High temperature curing leads to blooming of lead film, which is the chemical resistance layer, but impairs bonding with metal. 

Lead films can be deposited by pyrolysis of lead tetraethyl or tetramethyl ... 

There are materials, which can form varieties of nonstoichiometric compounds. For example, Pb02 can coexist as PbO where x can have values from 0 to 2. Among these oxides, most photoactive oxide is PbOo.8- If PbOo.8 oxide is to be prepared by anodic oxidation of lead, it is possible that surface of the lead film might contain other forms of oxides as well. Thus, a PEC cell prepared by anodization of lead may give a low photoresponse, not because PbOo.8 is an inappropriate material but because anodized surface may be contaminated with other forms of oxides as well. There seems to have no nondestructive technique available to confirm the uniformity of surface with photoactive species, especially of a large area electrode. Sharon and coworkers [111] has recently developed a laser scanning system to overcome this problem. A laser... 

Bobrowski, A., Krolicka, A., and Lyczkowska, E. (2008) Carbon paste electrode plated with lead film. Voltammetric characteristics and application in adsorptive stripping voltammetry. Electroanalysis, 20, 61 -67. 

Tyszczuk-Rotko, K. (2012) New voltammetric procedure for determination of thiamine in commercially available juices and pharmaceutical formulation using a lead film elecfiode. Food Chem., 134,1239-1243. 

A lead hydride has been reported from the bombardment of lead films by hydrogen atoms35. 

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... 

Tin lead films have been the standard (most common) tin-based plating for over 40 years and have never been shown to have any whisker growth under ambient usage conditions. High clamp-stresses on parts like bolted connectors can result in whisker growth in tin-lead films. 

The electrodes related to BiFEs or BEs, respectively, are mainly lead film-plated electrodes (PbFEs " ) and antimony film electrodes (SbFEs ) plus their possible variants. Especially the arrangement of SbFEs may offer surprisingly good performance in the determination of Cd and Pb in water samples requiring acidification to pFl 2, which is not very suitable for BiFEs responding optimally in acetate-buffered solutions. ... 

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