Chemical vapor deposition, modeling properties

The classical approach of conduction does not include the above time lag concept or the wavelike response. It expects a delta function-like response of temperature without any time lag with respect to the applied heat pulse. In the classical approach, we use phenomenological models which do not require any knowledge of the mechanism of energy transport or the microstructure of the solids. Fourier s law of heat conduction uses thermal conductivity as a material property which is a function of temperature. This thermal conductivity depends on the microstructure of the solids, which the thermal conductivity data does not show. For example, thermal conductivity of diamond can span an order of magnitude depending on the type of microstructure obtained by chemical vapor deposition. Thermal conductivity of natural... 

Chapter 10 deals with composite films synthesized by the physical vapor deposition method. These films consist of dielectric matrix containing metal or semiconductor (M/SC) nanoparticles. The film structure is considered and discussed in relation to the mechanism of their formation. Some models of nucleation and growth of M/SC nanoparticles in dielectric matrix are presented. The properties of films including dark and photo-induced conductivity, conductometric sensor properties, dielectric characteristics, and catalytic activity as well as their dependence on film structure are discussed. There is special focus on the physical and chemical effects caused by the interaction of M/SC nanoparticles with the environment and charge transfer between nanoparticles in the matrix. 

Model electrodes with a dehned mesoscopic structure can be generated by a variety of means, e.g., electrodeposition, adsorption from colloidal solutions, and vapor deposition and on a variety of substrates. Such electrodes have relatively well-dehned physico-chemical properties that differ signihcantly from those of the bulk phase. The present work analyzes the application of in-situ STM (scanning tunneling microscopy) and ETIR (Eourier Transformed infrared) spectroscopy in determining the mesoscopic structural properties of these electrodes and the potential effect of these properties on the reactivity of the fuel cell model catalysts. Special attention is paid to the structure and catalytic behavior of supported metal clusters, which are seen as model systems for technical electrocatalysts. 

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