Cadmium electrode, current-voltage

Coulometric determinations of metals with a mercury cathode have been described by Lingane. From a tartrate solution, copper, bismuth, lead, and cadmium were successively removed by applying the appropriate cathode potential, which was selected to correspond to a region of diffusion-controlled current determined from current-voltage curves with a dropping mercury electrode. With a silver anode, iodide, bromide, and chloride can be deposited quantitatively as the silver salt. By controlling the anode potential, Lingane and Small determined iodide in the presence of bromide or chloride. The separation of bromide and chloride, however, was not successful because solid solutions were formed (Section 9-4). 

Figure 1.31 Equilibrium potentials of the negative and positive electrodes in a nickel/ cadmium battery, and current/voltage curves for O2 and H2 evolution and O2 reduction.

Figure 2.22 shows the discharge characteristics at the 0.2, 1, and 3 C rate. The high-rate discharge characteristics of a nickel-MH battery compare unfavorably with those of a nickel-cadmium battery, because the specific surface area of the MH electrode is smaller than that of the cadmium electrode. Since the battery voltage drops dramatically if the discharge current exceeds 3 C, it is better to use a... 

FIG. 16 Current versus bias voltage for a CdS nanoparticle on the end of an STM tip. The CdS particles were formed by exposing a bilayer of cadmium arachidate on the STM tip to H2S gas. The other conducting surface is a highly oriented pyrolytic graphite electrode. The inset is a plot of differential conductance versus the bias voltage. (Reproduced with permission from Ref. 202. Copyright 1996 National Academy of Sciences, U. S. A.)... 

C19-0095. After use, a nickel-cadmium battery has 1.55 g of Cd (OH)2 deposited on its anode. It is inserted in a recharger that supplies 125 inA of current at a voltage of 1.45 V. (a) To which electrode, Ni or Cd, should the negative wire from the charger be connected Write the half-reaction occurring at this electrode during charging, (b) Compute the time in hours needed to convert all 1.55 g of Cd (OH)2 back to Cd metal. 

Ottova et al. looked at two-compartment semiconductor-septum electrochemical photovoltaic cells with cadmium selenide and cadmium selenide telluride for water photolysis [126], They used cells consisting of two chambers separated by a CdSe or CdSe/CdTe bipolar electrode. The bipolar electrodes were prepared by painting a CdSe slurry on a metal substrate or by ultrasound-aided electrodeposition from CdSe solution in ZnCl2. The photoresponse (voltage and current output) and hydrogen yield from photo-induced electrolysis of H20 in the dark chamber of the cell were evaluated as a function of CdSe preparation method. The ultrasound-aided deposition technique gave excellent coatings of CdSe. 

Fatas, et al. (63), have also done a study on the electrodeposition of CdS from nonaqueous solutions, in this case on stainless steel and tin oxide. They studied two solvents DMSOandPC. Thesolutionswere0.19 M sulfur and 0.055 M cadmium chloride in DMSO, and PC saturated with sulfur, cadmium chloride and potassium chloride. The depositions were carried out at a constant current at 120°C. All voltages were referenced to a cadmium/cadmium chloride electrode. 

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