Conductive glass electrodes

The dye-sensitised solar cell (DSSC) is constructed as a sandwich of two conducting glass electrodes filled with a redox electrolyte. One of the electrodes is coated, using a colloidal preparation of monodispersed TiOj particles, to a depth of a few microns. The layer is heat treated to rednce resistivity and then soaked in a solution of the dye until a monomolecnlar dispersion of the dye on the TiO is obtained. The dye-coated electrode (photoanode) is then placed next to a connter electrode covered with a conducting oxide layer that has been platinised , in order to catalyse the reduction of the mediator. The gap between the two electrodes is filled with an electrolyte containing the mediator, an iodide/triodide conple in acetonitrile. The structure is shown schematically in Fignre 4.29. 

Figure 11 The absorption spectrum of a 0.2-mM NBB dye solution recorded at different time intervals following electrochemically assisted photocatalysis. An immobilized Ti02 particulate film cast on a conducting glass electrode was maintained at an electrochemical bias of 0.8 V SCE during the photocatalytic degradation experiment. (From Ref. 265.)...

Photoeletrochemical cells usually employ a conducting glass electrode coated with a thin film of a semiconducting material that is placed in contact with a suitable redox couple (e.g., I3 /H) responsible for mediating the ET to a second electrode (Fig. 48). 

Figure 48. Scheme of a photoelectrochemical cell constituted by two conducting glass electrodes (FTO = fluorine doped tin oxide) one side coated with a film of Ti02, as the semiconducting photoactive interface and a redox mediator (la/I ) dissolved in methoxipropionitrile. A thin platinum film is also employed to improve the electrical contact with the second electrode. 

Figure 8. Photocurrent action spectrum of a CdS covered indium tin oxide (ITO) conducting glass electrode (0.5 V vs. Ag/AgCI) as obtained upon chopped irradiation (light and dark phases were 15 s) MeOH, 0.04 M NBU4CIO4.

Electochemical cell with suitable electrodes, carbon rod, conducting glass electrode, SCE... 

The solution is poured into the electrochemical cell. This cell is flat bottomed and cylindrical in construction and has a gas inlet and two side-arms with female Quickfit joints into which are inserted two male joints terminated with sintered-glass frits. The conducting-glass electrode is then attached to a crocodile clip with a long wire contact, which is clipped so that the crocodile clip is above the surface of the liquid. The graphite rod and SCE are then placed in the side-arms provided (separated from the solution by a sintered-glass frit). 

Polyaniline salts of the approximate average emeraldine oxidation state may also be conveniently synthesized by electrochemical oxidation of aniline in aqueous acid media, as thin films on metal or conducting glass electrodes.Under certain potential/current conditions, the polymer is formed as a matt of 2,000A fibrils. 

Peng and Guarr " and Trollund et al. reported on the electrocatalytic oxidation of hydrazine at a GCE modified with CoTAPc polymer, with a well-defined catalytic peak at -0.30 Table 7.8. The central Co(II) metal was found to act as the electronic receptor for hydrazine ". H2TAPC on GCE or conducting glass electrodes has also shown catalytic activity towards the oxidation of hydrazine. Ebadi reported on the use of a dimeric (RuPc)2 complex for the electrocatalytic reduction of hydrazine to nitrogen in basic media. The mechanism for this process may be similar to that reported below for hydroxylamine. The potentials for the oxidation of hydrazine on FeTSPc and CoTSPc are similar. Table 7.8. 

The photcwurrent measurements establish that injection of charges occurs from the excited state of the dye to the conduction band of the semiconductor, but does not say anything about the identity of the dye excited state involved. Luminescence and time-resolved (transient) absorption studies on dye-semiconductor colloids and dye-coated films on conducting glass electrodes have been useful to establish the identity of the excited state and energetics of the sensitization process. 

An FLC OASLM is made up from a thin layer of FLC sandwiched between a conductive glass electrode and a photoconductive layer, as illustrated in Fig. 9. There is still an external electrical field applied, but this is common for the whole OASLM and is... 

The electrochromic device consists of an alternating layer structure comprising a transparent substrate coated with an ITO coating, a cathode, an ionic conductor, an anode, and an another ITO-coated substrate. Both anode and cathode undergo redox reactions upon application of electric current between the conductive glass electrodes. The redox reactions lead to the reversible formation of colored species in the specific layer while at the same time electrons and cationic species (usually Li or H" ) move through the ionic conductor toward the appropriate electrode. 

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