Chemistry on metal oxide surfaces
We are applying for continued allocation on the Triolith supercomputer cluster in order to extend and finish our ongoing computational study of the physical and chemical surface properties of cuprite (Cu2O). In parallel to this we intend to study other metal oxide materials for solar cell applications. The aim of the cuprite study is to provide insight into fundamentally and industrially important processes taking place on the oxide surface. These include water splitting, corrosion, sulfidation and catalytic behavior in methanol synthesis and in the low-temperature water-gas shift reaction. Furthermore, since copper (one of our most common base materials) is covered by an oxide film in most real applications, understanding of the behavior of Cu2O is of broad general interests. One particular application of interest is the long-term storage of spent nuclear fuel in copper canisters. Both the cuprite and solar cell studies will be carried out in close collaboration with experimental groups at KTH and Stockholm University (SU). Density functional theory (DFT) computations will be used in conjunction with experimental data obtained by electron microscopy techniques (STM), electron diffraction (LEED), sum frequency generation spectroscopy (SFGS) and photoelectron spectroscopy (XPS, UPS) at KTH, SU and Maxlab facilities. In the solar cell project, we will work side-by-side with to the synthetic group of Licheng Sun including world-leading experts in the field. In previous parts of the cuprite project we have been able to characterize the structure of the Cu2O(100)-surface (Soldemo et al., J. Phys. Chem. C, 2016, 120, 4373–4381), describe the behavior of water on the same surface (Stenlid et al., Phys. Chem. Chem. Phys., 2016, 18, 30570-30584) as well as study the initial sulfidation process of different Cu2O surfaces (Stenlid et al., Corros. Eng. Sci. Techn., DOI: 10.1080/1478422X.2017.1284393). Using DFT combined with experimental studies, funded in part by Vetenskapsrådet (VR), we have also been able to obtain insight into the interactions of the socioeconomically and industrially important methanol, carbon monoxide and sulfur dioxide molecules on the Cu2O(100) and (111) surfaces with implications to, for instance, corrosion science and the development of renewable fuels. The studied surfaces will be further analysis by our newly developed reactivity descriptors (Brinck et al., J. Phys. Chem. A, 2016, 120, 10023-10032), which are able to characterize local properties of metal and oxide surfaces that have previously been unattainable by tools of comparable computational cost. We envisage these tools to be of particular use in the characterization of charge separation and transportation in the study of solar cell materials.