Peter W. Voorhees

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—Synchrotron X-ray computed tomography (SXCT) is increasingly being used for 3D imaging of material samples at micron and finer scales. The success of these techniques has increased interest in 4D reconstruction methods that can image a sample in both space and time. However, the temporal resolution of widely used 4D reconstruction methods is severely(More)
A method is described for quantitatively analyzing the level of interconnectivity of solid-oxide fuel cell electrode phases. The method was applied to the three-dimensional microstructure of a Ni-Y2O3-stabilized ZrO2 (Ni-YSZ) anode active layer measured by focused ion beam scanning electron microscopy. Each individual contiguous network of Ni, YSZ, and(More)
We used x-ray nanotomography to characterize the three-dimensional ͑3D͒ morphology and topology of dealloyed nanoporous gold after coarsening. The interface shape distribution obtained from the nanotomography measurement shows that the coarsening does not proceed by bulk diffusion. The surface normal distribution shows that the morphology of the nanoporous(More)
During crystal growth, faceted interfaces may be perturbed by defects, leading to a rich variety of polycrystalline growth forms. One such defect is the coherent Σ3 {111} twin boundary, which is widely known to catalyze crystal growth. These defects have a profound effect on the properties of many materials: for example, electron-hole recombination rates(More)
The vapor-liquid-solid (VLS) process of semiconductor nanowire growth is an attractive approach to low-dimensional materials and heterostructures because it provides a mechanism to modulate, in situ, nanowire composition and doping, but the ultimate limits on doping control are ultimately dictated by the growth process itself. Under widely used conditions(More)
Integrated intensity of the amorphous peak as a function of temperature under a constant heating rate of 0.5 C/min. The solid line is the fit to the theory. The crystallization process of amorphous ZITO thin films was studied using x-ray diffraction. The resulting intensity peaks can be fit to a classical Johnson-Mehl-Avrami-Kolmorgrov relation for the(More)
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