Quantum molecular dynamics simulations of α-Al2O3(0001)/3C-SiC(111) interfaces reveal profound effects of thermal annealing for producing strong interfaces consisting solely of cation-anion bonds and their consequence on interfacial structures. A Si-terminated SiC surface and Al2O3 form a stronger interface (Si-interface) with a Si-O bond density of 12.2  nm(-2), whereas the C interface has an ...

We report the structure and stability of ceria units deposited on the surface of γ-Al2O3 or incorporated in its cavities, as determined by periodic density functional calculations. Ceria species are modeled as CeO2 or Ce2O4 moieties or as a small nanoparticle, Ce13O26, on the (100) and (001) surfaces of a γ-Al2O3 slab. Among the studied structures the incorporation of Ce(4+) ions in cavities of...

Single-atom catalysts have attracted much interest recently because of their excellent stability, high catalytic activity, and remarkable atom efficiency. Inspired by the recent experimental discovery of a highly efficient single-atom catalyst Pd1/γ-Al2O3, we conducted a comprehensive DFT study on geometries, stabilities and CO oxidation catalytic activities of M1/γ-Al2O3 (M=Pd, Fe, Co, and Ni)...

Friction stir welding is a solid state joining process first used for welding of Aluminum and its alloys, is now employed for welding of polymers and composite materials. Polypropylene (pp) is one of polymer materials used in many applications due to its good performance, high strength to weight ratio and excellent processing properties, its application is limited due to its weak abrasive prope...

The effect of 5 different surface conditioning methods on bonding of metal brackets to cast dental alloys was examined. The surface conditioning methods were fine (30-microm) or rough (125-microm) diamond bur, sandblasting (50-microm or 110-microm aluminum oxide [Al2O3]), and silica coating (30-microm silica). Fifty disc-shaped specimens of 5 different alloys (gold-silver, palladium-silver, nic...

A reliable and CMOS-compatible deposition process for amorphous Al2O3 based active photonic components has been developed. Al2O3 films were reactively sputtered, where process optimization was achieved at a temperature of 250 C, with a deposition rate of 8.5 nm/min. With a surface roughness of 0.3 nm over a 1 μm area, background optical losses as low as 0.1 dB/cm were obtained for undoped films...

Atomic layer deposition (ALD) has been widely reported as a novel method for thin film encapsulation (TFE) of organic light-emitting diodes and organic photovoltaic cells. Both organic and inorganic thin films can be deposited by ALD with a variety of precursors. In this work, the performances of Al2O3 thin films and Al2O3/alucone hybrid films have been investigated. The samples with a 50 nm Al...

Dissipative two-level systems (TLS) have been a long-standing problem in glassy solids over the last fifty years, and have recently gained new relevance as sources of decoherence in quantum computing. Resonant absorption by TLSs in the dielectric poses a serious limitation to the performance of superconducting qubits; however, the microscopic nature of these systems has yet to be established. B...