Metal-solution interphase formation

Figure 4.2. Formation of metal-solution interphase equilibrium state n = %.

The Chapter by N. Garcia, V. Climent and J. Feliu provides a lucid and authoritative overview of the use of laser-pulsed induced temperature variations at the platinum single-ciystal/aqueous solution interphases and of the rigorous analysis of these experiments via Gibbs thermodynamics to extract new and very valuable information on the stracture and reactivity of the metal/solution interphase. The authors show how some key interfacial properties can be evaluated directly via this elegant analysis, such as the entropy of charge-transfer adsoibed species, the entropy of formation of the interfacial water network and the potential of water reorientation. 

Usually, in a given electrolyte solution, there is a similarity in the mechanism of SEI formation on carbon and metallic lithium.285 353 354 The mechanisms of SEI formation on lithium in numerous electrolytes are investigated since about three decades. In about the last 15 years, the focus continuously shifted from metallic lithium to carbon. There are a huge number of publications covering manifold aspects of the carbon s reactivity with the electrolytes and/or the SEI formation. The reader of this chapter is referred to the books published in this field recently and especially to the primary literature listed therein. Examples include Nonaqueous Electrochemistry from 1999 edited by Aurbach,355 Advances in Lithium-Ion Batteries from 2002 edited by van Schalkwijk and Scrosati,356 and Lithium-Ion Batteries Solid-Electrolyte Interphase from 2004 edited by Balbuena and Wang.281... 

Abstract The formation of stable metal/polymer joints is an enormous challenge in material sciences. Good adhesion requires an interphase which is able to specifically interact with the metal substrate as well as with the second component. Furthermore, the interphase should compensate thermally generated mechanical tensions between the two adhering components. It will be shown that statistic copolymers of poly(vinyl formamide) and poly(vinyl amine) (PVFA-co-PVAm) are potential candidates for adhesion promoters. The polyelectrolyte character of the copolymers allows to apply them from its aqueous solutions. The primary amino groups exhibit the copolymers as highly reactive to metal surfaces as well as to the second joint partner. The... 

These early observations serve to introduce a subject—the formation of mobile ions in solution—that is as basic to electrochemistry as is the process often considered its fundamental act the transfer of an electron across the double layer to or from an ion in solution. Thus, in an electrochemical system (Fig. 2.1), the electrons that leave an electronically conducting phase and cross the region of a solvent in contact with it (the interphase) must have an ion as the bearer of empty electronic states in which the exiting electron can be received (electrochemical reduction). Convo sely, the filled electronic states of these ions are the origin of the electrons that ente the metal in the... 

The concentration of defects may increase at the interphase boundary during the preparation of mixed catalysts, and these would then display higher catalytic activity. Frequently the changes in catalytic activity of mixed contacts are due to formation of spinels. The effect of a polyphase system of this kind, consisting of metal oxide spinels (often as solid solutions), on the rates of various reactions is a complex problem. 

The effect of the inhibitor is generally rather complex (Fig. 9-5) (K ilm n, 1994). The situation may be even more complicated in the case of an interphase (oxide, hydroxide, salts, etc.) existing in neutral aqueous solutions (Fig. 9-6) (Kdlmdn, 1994). The inhibitor can modify the surface layer by precipitation, pore plugging, enhanced film growth, etc. In some cases, polymer layers can even be formed by the inhibitor. Some surface active agents may act as inhibitors through hydrophobicity. Therefore the inhibition effect may be due to film formation, adsorption on metal surfaces or on... 

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