Simple Strategy Generating Hydrothermally Stable Core–Shell Platinum Catalysts with Tunable Distribution of Acid Sites

Abstract

There are critical needs for platinum catalysts with high hydrothermal stability and tunable Pt–acid site proximity, which could not be achieved via traditional methods. Here, we describe a simple strategy (SiO2 alumination combined with controlled removal of the capping agent) through which Pt-based core–shell catalysts that tolerant both high-temperature steam and boiling water can be obtained. More importantly, this strategy allows precise control of the distance between acid sites and Pt; thus, the interfacial electronic interaction can be cut off without prohibiting the spillover of adsorbed species. This tunable structure not only helps to unravel the mechanism of C3H8 oxidation over acidic Pt catalyst but also increases the N2 selectivity for NOx selective catalytic reduction. Given that the component of both the “core” and “shell” can be changed easily, this strategy should have wide application in mechanism exploration as well as the development of catalysts for various reactions.