Electrocatalysis – Heterogeneous

Abstract

The present article surveys the state of the art of electrocatalysis, laying stress on the present knowledge and understanding. The links between electrocatalysis and catalysis are analyzed, demonstrating the similarity of catalytic and electrocatalytic systems. Electrochemical methods for the characterization and preparation of catalysts are discussed. Results concerning electrochemical activation of catalysis are presented. Fundamental aspects of electrocatalysis are approached in terms of electrochemistry, analyzing the role of the nature and surface structure of the electrode/catalyst in electrocatalytic processes. Electrocatalytic hydrogenation/reduction processes are discussed in detail, with special attention to the reductive splitting of CO and COH bonds. Studies devoted to the electrocatalytic reduction of carbon dioxide are also considered with respect to the great practical importance of the transformation of CO 2 into useful organic materials and fuels. Results connected with the reductive dehalogenation of various halogenated derivatives are also presented as these compounds are among the most widespread pollutants of the environment. Importance of attempts devoted to the electrocatalytic reduction of anions, first of all to the reduction of nitrate, motivated by their relevance to pollution control is emphasized. Problems of electrocatalytic oxidation of small organic molecules (formic acid, formaldehyde, and methanol) are discussed in detail, considering the potential use of these molecules as fuels in direct fuel cells. Special attention is paid to the electrocatalytic oxidation of diols and polyols.