Platinum phthalocyanine, direct

To prepare the standardized dispersion electrode, a mixture of 100 mg soot, 100 g 97% sulfuric acid and 100 mg pigment was stirred direct into the dilute sulfuric acid of the measuring vessel, so that the concentration of sulfuric acid in the electrolyte after stirring in was about 4.5 N. The current collector electrode was a gold-platinum mesh (90/10) of about 4.5 cm2 area. The current/voltage characteristics shown in Fig. 12 make it possible to compare CoTAA with various phthalocyanines. 

An X-ray study of the structure of the phthalocyanines. Part I. The metal-free, nickel, copper, and platinum compounds, J. M. Robertson, J. Chem. Soc., 1935,615, An X-ray study of the phthalocyanines. Part II. Quantitative structure determination of the metal-free compound, J. M. Robertson, J. Chem. Soc., 1936, 1195 An X-ray study of the phthalocyanines. Part III. Quantitative structure determination of nickel phthalocyanine, J. M. Robertson and I. Woodward, J. Chem. Soc., 1937, 219 An X-ray study of the phthalocyanines. Part IV. Direct quantitative analysis of the platinum compound, J. M. Robertson and I. Woodward, J. Chem. Soc., 1940, 36. 

Haak and Nolta (141, 14%) have observed rectifying phenomena when polycrystalline samples of metal-free or metal phthalocyanines are compressed between different metal electrodes. A small amount of a liquid polar impurity was found to be essential for rectification to occur. The rectification ratio (ratio of conductance in forward and reverse directions, the forward direction being movement of electrons from the least noble electrode to the sample) varies from 25 to 500. The latter value is obtained when copper phthalocyanine is sandwiched between either platinum and silver, or silver and aluminum, electrodes. Kleitman (188) has also demonstrated that metal-free phthalocyanine can act as a rectifier. 

---