The surface sensitivity of a catalyst affects several aspects of the catalytic process:
1. Active Sites: Different surface structures expose different types and numbers of active sites. For example, the [(111) facet of platinum](), which has a close-packed structure, exhibits different catalytic properties compared to the (100) or (110) facets. 2. Adsorption Strength: The interaction strength between reactants and the catalyst surface varies with surface orientation. Stronger adsorption can lead to higher activity but may also cause [surface poisoning]() if the reactants or products bind too strongly. 3. Reaction Pathways: The surface structure can influence the preferred reaction pathways, affecting the overall [selectivity]() of the process. For instance, the surface sensitivity of [copper catalysts]() is crucial in the selective hydrogenation of [carbon dioxide](). 4. Defects and Promoters: Surface defects, such as steps, kinks, and vacancies, often act as highly active sites. Additionally, the presence of promoters can alter the electronic properties of the surface, enhancing catalytic performance.
