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Enhancing The Activity Of Electrode Materials In Hydrogen Economy
Bok av Perica Paunovic
he subject of this book is to show the approaches to enhance electrocatalytic activity of pure metals. As a main approaches can be distinguished: i) hypo-hyper d-interaction of the catalyst's components, ii) synergetic interaction between the catalyst's components, explained by "d-band center theory" and iii) the choice of support material. According to Jaki's hypo-hyper d-concept, the mixture of hyper d- electronic transition metals (good individual catalysts) with hypo d- electronic transition metals or their compounds (poor catalysts) exhibits pronounced synergetic effect of electrocatalytic activity. According to "d-band center theory", the position of d-band has leading role in determining the affinity of d-metals to adsorption of variety of adsorbates, such as H, O, CO etc. Generally, the support material influence on the catalytic activity through the following characteristics: i) highly developed surface area to provide better dispersion of the nano-scaled catalytic particles; ii) high electric conductivity to provide efficient electron transfer to ions involved in the electrochemical reactions and iii) mechanical and chemical stability.