Composition-dependent morphologies of CeO nanoparticles in the presence of Co-adsorbed HO and CO: a density functional theory study.

Catalytic activity is affected by surface morphology, and specific surfaces display greater activity than others. A key challenge is to define synthetic strategies to enhance the expression of more active surfaces and to maintain their stability during the lifespan of the catalyst. In this work, we outline an approach, based on density functional theory, to predict surface composition and particle morphology as a function of environmental conditions, and we apply this to CeO nanoparticles in the presence of co-adsorbed HO and CO as an industrially relevant test case.

Structural Dynamics, Phonon Spectra and Thermal Transport in the Silicon Clathrates.

The potential of thermoelectric power to reduce energy waste and mitigate climate change has led to renewed interest in "phonon-glass electron-crystal" materials, of which the inorganic clathrates are an archetypal example. In this work we present a detailed first-principles modelling study of the structural dynamics and thermal transport in bulk diamond Si and five framework structures, including the reported Si Clathrate I and II structures and the recently-synthesised C24 phase, with a view to understanding the relationship between the structure, lattice dynamics, energetic stability and thermal transport. We predict the IR and Raman spectra, including ab initio linewidths, and identify spectral signatures that could be used to confirm the presence of the different phases in material samples.

Unraveling the Impact of Graphene Addition to Thermoelectric SrTiO and La-Doped SrTiO Materials: A Density Functional Theory Study.

We present a detailed theoretical investigation of the interaction of graphene with the SrO-terminated (001) surface of pristine and La-doped SrTiO. The adsorption of graphene is thermodynamically favorable with interfacial adsorption energies of -0.08 and -0.

Controlling the {111}/{110} Surface Ratio of Cuboidal Ceria Nanoparticles.

The ability to control the size and morphology is crucial in optimizing nanoceria catalytic activity as this is governed by the atomistic arrangement of species and structural features at the surfaces. Here, we show that cuboidal cerium oxide nanoparticles can be obtained via microwave-assisted hydrothermal synthesis in highly alkaline media. High-resolution transmission electron microscopy (HRTEM) revealed that the cube edges were truncated by CeO{110} surfaces and the cube corners were truncated by CeO{111} surfaces.

Impact of Hydrogen on the Intermediate Oxygen Clusters and Diffusion in Fluorite Structured UO.

Uranium dioxide is the most prevalent nuclear fuel. Defect clusters are known to be present in significant concentrations in hyperstoichoimetric uranium oxide, UO, and have a significant impact on the corrosion of the material. A detailed understanding of the defect clusters that form is required for accurate diffusion models in UO.