Bottom-up synthesis of a pyramid-type (Pt/4nmCeO2)/SiO2 catalyst via a surface reduction strategy

Abstract

The interfaces in heterogeneous catalysts play an important role in their performances by either directly providing active sites through the synergistic effects from different catalyst compositions or indirectly modulating the state of active sites. However, constructing abundant interfaces in heterogeneous catalysts is a key scientific challenge since it requires the high dispersion of all catalyst compositions involved in substrate activation. A surface reduction strategy is proposed as the solution for this challenge, which creates a pyramid-type catalyst, (Pt/4nmCeO₂)/SiO₂, with maximized interfacial Pt–CeO₂ sites as an example. Pt is chemically bound in surface reductive centers of 4 nm CeO₂ nano-islands, generating stable Pt²⁺ sites with moderate hydrogenation capacity compared to Pt⁰ sites on bulk CeO₂ and SiO₂. This work facilitates the development of heterogeneous catalysts by presenting a high level of controlling the local chemical environment within nanomaterials.