It should be noted that such CuO(100) layers have the same lattice constant with Cu 2O surface (a = b = 4.27 Å), which is different from normal CuO according to previous reports 14. Since the thickness of CuO layer is >10 nm, we only use the CuO/Ag model in our DFT simulations due to the limitation of computational resources. Despite the existence of better performing materials 16– 18, our design can still serve as a sample model to study the promotion of charge polarization on catalytic activity. Compared with previous reported CuO based catalysts 14– 18, our design achieves complete conversion of CO at relatively low temperature (150 ☌), which performs better than bare CuO/Cu 2O 14 or CuO 15 (Table 1). Following this first treatment cycle, the exposed Cu 2O(100) surface was then oxidized to form a layer of CuO(100) surface. 1, a Cu 2O(111) surface was first deposited on a flat Ag(111) substrate, tailored to expose a Cu 2O(100) surface. To acquire deeper insight into surface polarization, recently we designed a novel semiconductor-metal interfacial structure (CuO/Ag) for CO oxidation 13. The fundamental problem is the limited understanding of the nature of surface polarization, a barrier which seriously hinders the further practical application of heterogeneous catalysts. Although tremendous attempts have been made, using methods such as shape-controlling 7, chemical doping 8, crystal-plane-controlling 9, use of an external electric field 10, etc., it still remains a considerable challenge to precisely tailor the surface charge state of these solid materials so as to enhance both activity and stability simultaneously 11, 12. However, precise control of charge location at the atomic level still remains a challenge 6. Their high catalytic activity is normally ascribed to the characteristically high charge transfer efficiency between adsorbed gas molecules and the catalyst surface, a quality which is highly dependent on the surface charge density of active sites 4, 5. Heterogeneous catalysts of various reactions such as CO oxidation have attracted widespread attention due to their high efficiency, benign environmental impact, and durability 1– 3.

Cuo oxygen charge