Microstructural evolution in Pt-implanted polycrystalline Al2O3

Microstructural evolution of helium-implanted a-SiC

Helium has a decisive effect on the microstructure of silicon carbide materials after implantation and subsequent annealing. A dense population of bubbles and dislocation loops is already observed at relatively low displacement doses after annealing of helium-implanted a-SiC, while no visible damage appears after irradiation without helium implantation under otherwise equal conditions. The defe...

An operando emission spectroscopy study of Pt/Al2O3 and Pt/CeO2/Al2O3.

In situ time-resolved spectroscopic examination of catalysts based on well dispersed nanoparticles on metal oxides under transient conditions significantly facilitates the elucidation of reaction mechanisms. In this contribution, we demonstrate the level of structural information that can be obtained using high-energy resolution off-resonant spectroscopy (HEROS) to study 1.3 wt% Pt/Al2O3 and 1....

Hydrogen production from methanol decomposition over Pt/Al2O3 and ceria promoted Pt/Al2O3 catalysts

We present the activities and selectivities of Pt/Al2O3-based catalysts in the production of hydrogen from methanol through catalytic decomposition. For the decomposition reaction, the Pt and Pd catalysts promoted by ceria exhibit similar activity reaching 100% conversion at 315 C. Promoting with ceria had a positive effect on activity and selectivity. Among all catalysts, the 9% Pt– 10% CeO2/A...

Bounding box algorithm for three-dimensional phase-field simulations of microstructural evolution in polycrystalline materials.

Phase-field modeling has proven to be a versatile tool for simulating microstructural evolution phenomena, such as grain growth in polycrystalline materials. However, the computing time and computing memory requirements of a phase-field model pose severe limitations on the number of phase-field variables that can be taken into account in a practical implementation. In this paper, a sparse bound...

An emission spectroscopy study of Pt/Al2O3 and Pt/CeO2/Al2O3