Structural engineering of core–shell PtCu alloy catalysts for propane dehydrogenation: a DFT study

Propane dehydrogenation (PDH) is an economically efficient and environmentally friendly industrial process for producing propylene. However, the understanding of the structure-performance relationship of PtCu bimetallic catalysts in PDH remains limited. In this work, we systematically investigated a series of PtCu bimetallic catalysts, including the Pt-skin Pt_<i>x</i>Cu_<i>y</i> core-shell structures and Pt_<i>x</i>Cu_<i>y</i> alloys, using first-principles calculations and <i>ab initio</i> molecular dynamics to assess their stability, activity, and selectivity. The results show that PtCu@Pt(111) and PtCu₃@Pt(111) exhibit improved stability and performance compared to Pt_<i>x</i>Cu_<i>y</i> alloys, attributed to the electronic effect of Cu species and the compressive strain effect of the Pt-skin Pt_<i>x</i>Cu_<i>y</i> structures. Furthermore, we clarified the electron density at the Pt-C interface and its influence on the electronic interactions within the Pt-adsorbate complex, revealing the pattern of catalytic activity changes. Notably, PtCu@Pt(111) demonstrated stronger resistance to carbon deposition compared to Pt(111), thereby suppressing hydrogenolysis side reactions. This work provides critical insights for the rational design of efficient Pt-based catalysts for PDH <i>via</i> a doping strategy.