Résumé
Single atom catalysts (SAC) can offer appealing catalytic activity and selectivity for heterogeneous catalysis in general, [1] and for electrocatalysis for energy conversion devices in particular. [2] This presentation will describe some examples of studies on the aspects of synthesis, structural characterization and catalytic properties of Metal-Nitrogen-Carbon SACs for fuel cells, electrochemical H2O2 production and CO2 conversion. In many of these potential applications, Metal-Nitrogen-Carbon catalysts (with non-precious metal center) are however competing with precious metal-based catalysts, and the benefits of their lower cost must be balanced with their often lower activity and/or durability performances. Durability is especially a challenge, with the general tendency of M-N4 single metal atom sites to dynamically transform or to degrade as a result of exposure to highly oxidative or reductive conditions. [3-4] The presentation will discuss these broad aspects, fundamentally related to the nature of the M-Nx active sites and their achievable active site density.
