Surfaces, interfaces and adsorption

G. A. Parks, Surface energy and adsorption at mineral/water interfaces an introduction, in M. F. Hochella and A. F. White, eds., Mineral-Water Interface Geochemistry, The Mineralogical Society of America, Washington, D. C (1990). 

Section 8 deals with reactions which occur at gas—solid and solid—solid interfaces, other than the degradation of solid polymers which has already been reviewed in Volume 14A. Reaction at the liquid—solid interface (and corrosion), involving electrochemical processes outside the coverage of this series, are not considered. With respect to chemical processes at gas-solid interfaces, it has been necessary to discuss surface structure and adsorption as a lead-in to the consideration of the kinetics and mechanism of catalytic reactions. 

Surface Structure and Adsorption Properties at the Soiid/Vacuum Interface Heating Ru(OOOl) surfaces covered by submonolayer amounts of ft... 

This type of fully local potential has some limited use, e.g., to consider adsorption in a slowly varying external potential. It fails, however, to describe the most important phenomena such as surface tension and adsorption at most types of interfaces. These phenomena reflect in a fundamental way the nonlocal interactions in the fluid. The most obvious nonlocality of the free energy arises due to the range of the attractive or soft interactions represented by the second term in the equation of state, —The corresponding potential energy can be obtained by the functional... 

This type of functional, which we refer to as coarse-grained, can be used to calculate both surface tension and adsorption isotherms to quite good accuracy for many fluids and interfaces. It can also be used for screening problems in the theory of electrolytes. 

In the last two sections the formal theory of surface thermodynamics is used to describe material characteristics. The effect of interfaces on some important heterogeneous phase equilibria is summarized in Section 6.2. Here the focus is on the effect of the curvature of the interface. In Section 6.3 adsorption is covered. Physical and chemical adsorption and the effect of interface or surface energies on the segregation of chemical species in the interfacial region are covered. Of special importance again are solid-gas or liquid-gas interfaces and adsorption isotherms, and the thermodynamics of physically adsorbed species is here the main focus. 

R. Sprycha, Surface charge and adsorption of background electrolyte ions at anataseZelectrolyte interface, J. Colloid Interface Sci. 102(1), 173 (1984). 

X ray photoelectron spectroscopy (XPS) is powerful in identifying species present at the surface/interface and atoms or functional groups involved in acid-base interactions [116]. Since XPS measures the kinetic energy of photoelectrons emitted from the core levels of surface atoms upon X ray irradiation of the uppermost atomic layers, it can be used to characterize surface acid sites, in combination with base probe molecules adsorption. 

The fifth contribution by M. Putkonen and L. NiinistO presents an overview of Organometallic Precursors for Atomic Layer Deposition (ALD). The key principle of ALD in contrast to CVD is the exclusion of any gas-phase prereaction allowing the thin film growth to be fully controlled by surface reactions and adsorption/desorption kinetics. ALD is thus ideally suited for the growth of ultra-thin layers and atomically abrupt interfaces needed in future nanoelectronic devices. While CVD and ALD have many aspects in common, precursors suitable for ALD generally need to be much more reactive than those used for CVD. Another challenge is to combine low steric demand with very high selectivity of the surface reactions. 

Defay R, Prigogine L, Bellemans A and Everett FI, "Surface Tension and Adsorption", Wiley, New York, 1966. Feast WJ and Munro HS (Eds), "Polymer Surfaces and Interfaces", Wiley, Chichester, 1987. 

Surface reaction and adsorption at the liquid-solid interface... 

Miller, R., Fainerman, V.B., Aksenenko, E.V., Leser, M.E., and Michel, M. (2004). Dynamic surface tension and adsorption kinetics of p-casein at the solution-air interface. Langmuir. 20, ii -in. 

Parks, G.A., Surface energy and adsorption at mineral-water interfaces An introduction, Rev. Miner, 23, 133, 1990. 

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