Indium electrode

Electrode coated with lH,lH,2H,2H-perfluorodecanethiol. ) Electrolyticall deposited indium electrode. 

Reduction of carbon dioxide takes place at various metal electrodes. The main products are formic acid in aqueous solutions and oxalate, CO, and formic acid in nonaqueous solutions. An indium electrode is the most potential saving for C02 reduction. Due to the difference in optimum conditions between those for C02 reduction to formic acid and those for formic acid reduction to further reduced products, direct reduction of C02 in aqueous solutions without a catalyst to highly reduced products seems to be difficult at metal electrodes. However, catalytic effects of metal electrodes themselves have recently become more clear for example, on Cu, methane was detected, while on Ag and Au, CO was produced effectively in aqueous solutions. Furthermore, at a Mo electrode, methanol was obtained. The power efficiency is, however, still low at any electrode. 

Table 7.6 cites a few sample values of y as a function of concentration. Note how multi-valent anions and cations cause y to vary more greatly than do mono-valent ions. The implications are vast if an indium electrode were to be immersed in a solution of In2(S04)3 of concentration 0.1 mol dm-3, for example, then a value of y = 0.035 means that the activity (the perceived concentration) would be about 30 times smaller ... 

A p-type HgCdTe layer 12 is formed epitaxially on a substrate 11 of CdTe. Recessed regions 13B are formed between protruding regions 13A and 13B. N-type regions 14A-14C are formed to which connections are made by indium electrodes 16 and 17 after an insulating film 15 of ZnS has been formed. 

A photoelectric conversion device 10 is formed in a p-type HgCdTe substrate 11 and a CCD 20 is formed in a p-type silicon substrate 13. Indium electrodes 4a and 4b, which are connected to the photoelectric conversion device and the CCD, respectively, are covered on their sides with shape-memory metal layers 5a and 5b. Pressure bonding is used to couple the photoelectric conversion device to the CCD. Thereafter, the temperature is raised to return the shape-memory metal to its original shape, at the same time releasing mechanical stress in the indium electrodes. 

A ZnS coating 46 is used to encapsulate the detectors. A dielectric filler is deposited in the channels between the detector elements to provide a supporting surface for a common electrode and to provide lateral mechanical support for the detector elements. Next, diode junctions 54 of the detectors are created by ion-implantation of boron ions. Indium contact pads 56 are formed in holes formed in the coating 46, and a common indium electrode 58 is formed on top of the dielectric material 50. 

Kadyrov et al., who studied electrochemical hydrogen evolution on indium electrodes in the presence of an ultrasonic field [144], have also proposed a mechanism of ultrasound action on the cathodic reduction of indium [145]. Other workers have looked at the effect of ultrasound on the electroreduction of nickel and cobalt divalent ions catalyzed by ligands [146], obtaining similar results. 

The preparation, spectrum, and stability of indium(i) in aqueous solution have been described, concentrations of 3 x 10 mol 1 In being prepared by anodisation of an indium electrode. Conventional techniques have been used to investigate the reaction ... 

In the first step, a CO2 molecule diffuses towards the indium electrode, and gets adsorbed on its surface, where it is activated and the C02 radical anion forms (Equation 1.20). As C02 ion pairs with BMIM+, which reacts with methanol to form CHs-O-COO , where the unpaired electron is located on the oxygen atom that originates from methanol (Equation 1.21). Next, molecular hydrogen is released (Equation 1.22), and dimethyl carbonate is formed in a subsequent chemical reaction with methyl iodide (Equation 1.23). This procedure enabled the synthesis of dimethyl carbonate at reasonable Faradaic yields of 73.2-76%, at potentials from -1.7 to -1.9 V (vs. Ag) [68,147]. 

F. Liu, S. Liu, Q. Feng, S. Zhuang, J. Zhang and P. Bu, Electrochemical synthesis of dimethyl carbonate with carbon dioxide in l-butyl-3-methylimidazoliumtet-rafluoborate on indium electrode, Int.. Electrochem. Sci. 7,2012,4381-4387. 

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