First-principles insights into Pt<i>n</i>/ZnO(0001) catalyst: Regulation of metal-support interaction through surface polarity

Polar surfaces are prevalent in metal oxides, the interactions between surface species with polar surfaces are different from those with non-polar surfaces, a thorough understanding of the interactions is key to regulate the performance of heterogeneous catalysts. In this work, we delve into the interaction of Ptn (n=1–4) with polar ZnO(0001)-Zn and ZnO(0001¯)-O, and the influence of the surface polarity on the electronic structures and reactivity of Ptn by using density functional theory calculations. The results suggest distinct differences in electronic structures of two exposed terminations, leading to different interactions with Ptn. The interaction between Ptn and two terminations not only stabilizes the surface and clusters through polar compensation, but also induces opposite charges on the cluster at two terminations. Remarkably, the Pearson correlation coefficient reveals the interdependency between the electronic states of Ptn and its performance in terms of small molecule adsorption/activation. These observations demonstrate the crucial role of surface polarity in regulating the electronic states and catalytic performance of active sites, and offer a possible design principle for supported catalysts.