We have investigated a series of supported and unsupported nickel and cobalt catalysts, principally using neutron vibrational spectroscopy (inelastic neutron scattering, INS). For an alumina supported Ni catalyst we are able to detect hydrogen on the metal for the first time, all previous work has used Raney Ni. For an unsupported Ni foam catalyst, which has similar behaviour to Raney Ni but with a much lower density, the spectra show that there are approximately equal numbers of (100) and (111) sites, in contrast to Raney Ni that shows largely (111) sites. The observation of hydrogen on cobalt catalysts proved to be extremely challenging. In order to generate a cobalt metal surface, reduction in hydrogen at 250–300 °C is required. Lower temperatures result in a largely hydroxylated surface. The spectra show that on Raney Co (and probably also on a Co foam catalyst), hydrogen occupies a threefold hollow site, similar to that found on Co($$10\bar{1}0$$
10
1
¯
0
). The reduced surface is highly reactive: transfers between cells in a high quality glovebox were sufficient to re-hydroxylate the surface.
Open-celled metallic foams with their specific structural properties are attractive candidates for a wide range of applications in the field of catalyst supports, process, and energy technologies. However, the material is so far not introduced as an engineering material and needs to be characterized for the respective applications. The metallic foams, especially in combination with cover plates, have a high potential for applications as light weight and functional materials. In this article, an industrial manufacturing process is described, which allows to produce a wide range of different qualities of foam with a variety of tailored alloys and pore sizes. The foam material can be stacked and co-sintered with top layers to high-strength sandwich structures. The mechanical properties evaluated in shear and compression tests are promising for couple of aircraft applications
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