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Vi gratulerer Marie Nielsen med årets beste masteroppgave 🎉 17. jan. 2024 12:15
Årets masteroppgave tildeles Marie Nielsen ved LENS.
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Tracking deactivation of zeolite beta with and without a detailed structure model: XRD analysis and in situ studies 1. des. 2023 15:42
X-ray diffraction is extremely powerful to study the structure of well-ordered, crystalline materials. In this paper, researchers from the Catalysis Section, NAFUMA, the Swiss Norwegian Beamlines, and Haldor Topsoe A/S take it one step further, by developing models for advanced diffraction studies of a disordered material, namely the beta zeolite. Despite the tremendous structural complexity caused by the disorder, these new models make it possible to resolve the degree of deactivation of the zeolite catalyst from a single diffractogram.
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Variable temperature in situ TEM mapping of the thermodynamically stable element distribution in bimetallic Pt–Rh nanoparticles 25. sep. 2023 14:42
In-situ TEM experiments shows that the tendency for elemental mixing- or segregation to occur in Pt–Rh nanoparticles depends on the nanoparticle size and temperature. The smaller nanoparticles ( ≲ 13 nm) are stable in the solid solution configuration over the entire studied temperature range. Larger nanoparticles ( ≳ 13 nm) tends to segregate when cooled to room temperature. The results are of importance to understand the thermodynamics of this specific Pt–Rh nanoparticle system and it add value towards applications like catalysis, whereof e.g. supported Pt–Rh nanoparticles are attractive candidates for NH 3 slip abatement processes.
