We present some algorithms for improvements of band theory calculations based on the Korringa-KohnRostoker method and on the coherent potential approximation, in the cases of ordered metals and random alloys. The purpose of our work was to develop a code flexible enough to deal on equal footing with any lattice geometry. The algorithms proposed are designed to achieve an arbitrary accuracy and ...

The recent availability of shale gas has led to a renewed interest in C-H bond activation as the first step towards the synthesis of fuels and fine chemicals. Heterogeneous catalysts based on Ni and Pt can perform this chemistry, but deactivate easily due to coke formation. Cu-based catalysts are not practical due to high C-H activation barriers, but their weaker binding to adsorbates offers re...

The dynamic behavior and kinetics of the structural transformation of supported bimetallic nanoparticle catalysts with synergistic functions in the oxidation process are fundamental issues to understand their unique catalytic properties as well as to regulate the catalytic capability of alloy nanoparticles. The phase separation and structural transformation of Pt(3)Sn/C and PtSn/C catalysts dur...

In the present study, methods to enhance the oxygen reduction reaction (ORR) activity of sub-nanosized Pt clusters were investigated in a theoretical manner. Using ab initio molecular dynamics and Monte Carlo simulations based on density functional theory, we have succeeded in determining the origin of the superior ORR activity of Pt12 compared to that of Pt13. That is, it was clarified that th...

Three-dimensionally (3D) porous morphology of nanostructures can effectively improve their electrocatalytic activity and durability for various electrochemical reactions owing to big surface area and interconnected structure. Cyanogel, a jelly-like inorganic polymer, can be used to synthesize various three-dimensionally (3D) porous alloy nanomaterials owing to its double-metal property and part...

Chromitite lenses rich in the platinum-group elements (PGE) have recently been discovered in the deeper part of the mantle section of the northern part of the Oman ophiolite. In terms of stratigraphic level, there are two types of chromitite: Moho transition zone (MTZ) and mantle types. The mantle type can be further classified into two subtypes: PGE-poor and PGE-rich. Platinum-group minerals (...

Introduction Direct methanol fuel cells are very important as a clean, low cost and portable power source because of several environmental problems in traditional energy producing systems. Compared to the hydrogen fueled PEMFCs, direct methanol PEMFCs are more compact and can be used in power portable electric devices. Platinum is the most active electro-catalyst for the electro-oxidation of me...

The growth of vapor-deposited films of Rh, Pd, and Pt on Cu(100) at 300 K was followed by Auger-electron and low-energy ion scattering spectroscopies. A tendency (strong for Rh, weaker for both Pd and Pt) for Cu to remain on the surface as the film grows was observed, consistent with expectations based on surface energy considerations. The much smaller difference in behavior between Pt and Pd t...

Carbon nanotubes (CNTs) have been investigated in recent years as a catalyst support for proton exchange membrane fuel cells. Improved catalyst activities were observed and attributed to metal-support interactions. We report a study on the kinetics of methanol electro-oxidation on CNT supported Pt-Ru alloy nanoparticles. Alloy catalysts with different compositions, Pt53Ru47/CNT, Pt69Ru31/CNT an...

The rational design of catalysts by tailoring specific surface sites with different elements could result in high activity, selectivity, and stability. In this work, we show that *CO on-top O* adsorption energies are good descriptors for the catalysis CO oxidation reaction (COOR) on pure metals binary alloys. observed Brønsted–Evans–Polanyi (BEP) scaling relations COOR surfaces incorporated int...