Electrolytes borosilicate

In the broad use of the word polymer, ion-containing polymers are ubiquitous. They include inorganic substances such as silicate and borosilicate glasses discussed in Chapter 4, most biopolymers, solvent-swollen synthetic ion exchangers and some synthetic structural polymers. With few exceptions, these exhibit the characteristic feature of an electrolyte, ion mobility. In this chapter we consider the group of synthetic... 

To diminish electrode pore flooding, McHenry and Winnick [106] studied new membrane formulations which included borosilicate glass and zeolites. These showed improved electrolyte retention and polarization behavior as compared with MgO-based membranes. The reduction in flooding allowed the cell to handle three times the current for the same applied overpotential. The same authors [107] also found that Lao,8Sro.2Co03 electrodes reacted with the molten pyrosulfate electrolyte. Lithium-doped nickel oxide replacement electrodes, however, were not degraded. 

The three- or two-port photoelectrochemical ceUs (e.g.. Fig. 3.7b) should be made of material that is transparent to the illumination spectrum of interest. If UV irradiation is required, quartz windows must be used in the cell, as opposed to borosilicate glass which generaUy absorbs wavelengths below 360 nm. The distances between all electrodes should be minimized to limit the effect of electrolyte resistance on the electrochemical test. For electrical measurements, a low impedance ammeter can be used to measure the short-circuit current density. 

Fig. 19 Schematic depictions of (a) the preparation of a cobalt pyrite (C0S2) film electrode via the thermal sulfidation of a 100 nm thick cobalt film deposited over a titanium adhesion layer on a roughened borosilicate glass substrate by electron-beam evaporation and (b) the incorporation of an as-synthesized C0S2 film on glass into a CdS/ CdSe-sensitized thin-layer liquid-junction quantum dot-sensitized solar cell (QDSSC) filled with sulfide/polysulfide electrolyte to demonstrate the high QDSSC performance enabled by the C0S2 counter electrode. Reproduced from ref. 167 with permission from the American Chemical Society.

Equation (6.39) has been verified by a number of experiments. In classical experiments, a sphere falling in gravity toward a planar surface has been observed [633-635] see also Exercise 6.1. A typical experimental force versus distance curve, which is dominated by hydrodynamic drag, is shown in Figure6.5. In this experiment a borosilicate glass sphere of 18 pm diameter was moved toward a silicon wafer in aqueous electrolyte with 0.2 M KCl at 25 °C. Both surfaces are hydrophilic. The sphere is attached to an atomic force microscope cantilever of spring constant 0.26 N m . The cantilever was moved with a constant velocity of 40pm s toward... 

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