Potential of zero total charge

A novel nondestructive method for the determination of total charges and hence of EQ=Qy that is based on the CO displacement experiments has been worked out.795,796 This method has been applied to Pt(lll) and Pt(l 10) electrodes in contact with solutions at different pHs. For both Pt faces, the potential-of-zero total charge lies in a potential region similar to that forpc-Pt.8,10,11 It was found that thepztc depends on pH in different ways for Pt(l 11) and Pt(l 10), which demonstrates that not only is the pztc structure sensitive, but also that it varies with pH.795 The value of pztc for Pt(l 11) is more positive than that for Pt(l 10), and df j/dpHis higher for Pt( 111) than for Pt( 110). 

Attard GA, Ahmadi A. 1995. Anion-surface interactions. Part 3 N2O reduction as a chemical probe of the local potential of zero total charge. J Electroanal Chem 389 175-190. 

Attard GA, Hazzazi O, Wells PB, Chment V, Hertero E, Feliu JM. 2004. On the global and local values of the potential of zero total charge at well-defined platinum surfaces Stepped and adatom modified surfaces. J Electroanal Chem 568 329-342. 

Climent V, Gomez R, Orts JM, Aldaz A, Fehu JM. 1997. The potential of zero total charge of single-crystal electrodes of platinum group metals. In Korzeniewski C, Conway BE, eds. The Electrochemical Society Proceedings (Electrochemical Double Layer). Pennington, NJ The Electrochemical Society, pp. 222-237. 

Climent V, Gomez R, Eehu JM. 1999. Effect of increasing amount of steps on the potential of zero total charge of Pt(lll) electrodes. Electrochim Acta 45 629-637. 

Climent V, Herrero E, Eeliu JM. 2001. Positive shift of the potential of zero total charge of stepped Pt(lll) electrodes decorated by irreversibly adsorbed bismuth. Electrochem Comm 3 590-594. 

Fmmkin AN, Petrii OA. 1975. Potentials of zero total charge and zero free charge of platinum group metals. Electrochim Acta 20 347-359. 

Climent V, Garcia-Araez N, Henero E, Feliu JM. 2006. Potential of zero total charge of platinum single crystals A local approach to stepped surfaces vicinal to Pt(lll). Russ J Electrochem 42 1145-1160. 

It was demonstrated that there is a direct correspondence between the potential of zero total charge and the maximum rate of N2O reduction. 

The quantity considered here is the potential of zero free charge, which is not identical to the potential of zero total charge at the metal/solution interface. It is the former that determines the composition inside the diffuse double layer. 

Alvarez B, Climent V, Rodes A, Feliu JM. Potential of zero total charge of palladium modified Pt(lll) electrodes in perchloric acid solutions. Phys Chem Chem Phys 2001 3 3269-76. 

It is questionable whether a potential of zero charge could be defined uniquely and measured unambiguously. Indeed, in spite of a tremendous interest in the literature, this subject has remained inconclusive. The presence of adsorption processes led to the definition of a potential of zero total charge [Pg.222]

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