The role of titanium nitride supports for single-atom platinum-based catalysts in fuel cell technology.

As a first step towards a microscopic understanding of single-Pt atom-dispersed catalysts on non-conventional TiN supports, we present density-functional theory (DFT) calculations to investigate the adsorption properties of Pt atoms on the pristine TiN(100) surface, as well as the dominant influence of surface defects on the thermodynamic stability of platinized TiN. Optimized atomic geometries, energetics, and analysis of the electronic structure of the Pt/TiN system are reported for various surface coverages of Pt. We find that atomic Pt does not bind preferably to the clean TiN surface, but under typical PEM fuel cell operating conditions, i.

A first-principles study of ultrathin nanofilms of MgO-supported TiN.

As a first step towards a microscopic understanding of supported ultrathin nanofilms of TiN, we present state-of-the-art density-functional theory (DFT) calculations to investigate the interfacial properties of the TiN/MgO system as a function of film thickness. Optimized atomic geometries, energetics, and analysis of the electronic structure of the TiN/MgO systems are reported. In particular, we find that the work function of 1 ML of TiN(100) on MgO(100) exhibits a significant decrease, rationalized by the large surface dipole moment formation due to the changes in charge densities at the interface of this system.

Multi-field effect on the electronic properties of silicon nanowires.

The quantum confinement and electronic properties of silicon nanowires (SiNWs) under an external strain field ε and an electric field E-as well as both (ε plus E)-are systematically investigated using density functional theory. These two fields exist in working environments of integrated circuits. It is found that both ε and E lead to a drop of the band gap E(g)(ε,E) of the SiNWs.