Platinum solubility temperature effect

The precipitation is especially enhanced because mostly a saturated KC1 solution is used to decrease the -> junction potential. It should be noted that by changing KC1 for NaCl the potential of the saturated calomel electrode (SCE) will be varied which is due to the different solubilities. In the case of electrodes of the second kind the effect of temperature on the solubility has to be considered, too. It is of importance to prevent to exchange electrolytes between the main and the reference compartments. For instance, a leakage of chloride ions, which is strongly adsorbed at platinum, may influ-... 

Rate measurements on fine amorphous powder and colloids have been made by Doremus et al. (224) and by Friedberg (225). The effects of pH, temperature, and presence of salts were similar to those reported by others. More than 50 years ago, Dienert and Wandenbulcke (226) reported the basic facts that colloidal silica passed into solution as soluble silica, which was detectable colorimetrically with molybdic acid, and that alkalinity and salts were good catalysts for dissolution. They made an observation which apparently has never been followed up. They claimed that when salt is present, the dissolution rate is faster in a quartz container than in platinum and that in the absence of added salt, colloidal silica would pass into the soluble state when heated with water in quartz, but not in platinum. However, pH measurements were not made. 

Thin film metallization is often used to establish contact with a surface. In many cases, the contact involves reactions that form a layer of compound material between the metallization and the surface. For instance, in the deposition of platinum on silicon, a layer of platinum silicide is formed. The contact resistance involves not only the resistance between the metallization and the surface but the effect of the reaction layer, which can be a high resistivity material or present a potential barrier. In the extreme, the junction may be rectifying (i.e. current can flow in one direction easily but in the other with difficulty). The metallization material can also alloy with the substrate material. For example, gold will diffuse into silicon to some extent and the higher the temperature, the higher the solubility of gold in the silicon. 

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