The Synergy between Metal Facet and Oxide Support Facet for Enhanced Catalytic Performance: The Case of Pd-TiO₂

The demand for catalyst with higher activity and higher selectivity is still a central issue in current material science community. On the basis of first-principles calculations, we demonstrate that the catalytic performance of the Pd-TiO₂ hybrid nanostructures can be selectively promoted or depressed by choosing the suitable shaped Pd and TiO₂ nanocrystals. To be more specific, the catalytic activities of Pd nanoparticles enclosed by (100) or (111) facets can be promoted more significantly when dosed on the TiO₂(001) than on TiO₂(101) under irradiation. Such theoretical prediction has then been further verified by the experimental observations in which the Pd(100)-TiO₂(001) composites exhibit the highest catalytic performance toward the activation of oxygen among all the other shaped hybrid nanostructures. As a result, the selection of facets of support materials can provide an extra tuning parameter to control the catalytic activities of metal nanoparticles. This research opened up a new direction for designing and preparing catalysts with enhanced catalytic performance.