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In conclusion, this work reports an original methodology to convert pre-formed coordination networks into high- performance magnets. These RT molecule-based magnets

Fig. 86: Experimental (a) XANES and (b) FT-EXAFS spectra of Li0.7[CrII(pyz)2]Cl0.7·(THF) (obtained after post-synthetic reduction of CrIII(pyz)2Cl2), CrIII(pyz)2Cl2 and a square planar Cr(II) model compound at the Cr K-edge at RT.

PRINCIPAL PUBLICATION AND AUTHORS

Metal-organic magnets with large coercivity and ordering temperatures up to 242°C, P. Perlepe (a,b), I. Oyarzabal (a,c), A. Mailman (d), M. Yquel (a,b), M. Platunov (e), I. Dovgaliuk (f), M. Rouzières (a), P. Négrier (g), D. Mondieig (g), E.A. Suturina (h), M.-A. Dourges (i), S. Bonhommeau (i), R.A. Musgrave (a), K.S. Pedersen (a,j), D. Chernyshov (f), F. Wilhelm (e), A. Rogalev (e), C. Mathonière (b), R. Clérac (a), Science 370, 587-592 (2020); https:/doi.org/10.1126/science.abb3861 (a) Univ. Bordeaux, CNRS, Centre de Recherche Paul Pascal, UMR 5031, Pessac (France) (b) Univ. Bordeaux, CNRS, Bordeaux INP, ICMCB, UMR 5026, Pessac (France) (c) Chemistry Faculty, University of the Basque Country, Donostia-San Sebastián (Spain) (d) Department of Chemistry, University of Jyväskylä (Finland) (e) ESRF (f) Swiss-Norwegian Beamlines at the ESRF (g) Univ. Bordeaux, CNRS, Laboratoire Ondes et Matière d Aquitaine, UMR 5798, Talence (France) (h) Department of Chemistry, University of Bath (UK) (i) Univ. Bordeaux, CNRS, Bordeaux INP, ISM, UMR 5255, Talence (France) (j) Department of Chemistry, Technical University of Denmark (Denmark)

REFERENCES

[1] K.S. Pedersen et al., Nat. Chem. 10, 1056-1061 (2018). [2] P. Perlepe et al., Polyhedron 153, 248-253 (2018).

are much lighter than the conventional magnets and, therefore, of great relevance to aeronautics and spatial, mobile and wearable technologies.

Unravelling the formation of cobalt carbide in a Fischer-Tropsch synthesis catalyst

An in-situ study combining X-ray Raman scattering (XRS) spectroscopy and X-ray diffraction (XRD) performed at beamline ID20 provides insights into the Co L2,3-edges and C K-edge spectra for cobalt carbide (Co2C) formation in Co/TiO2 catalyst during Fischer-Tropsch Synthesis (FTS) reaction.

In FTS, a mixture of hydrogen (H2) and carbon monoxide (CO) reacts to produce different hydrocarbons (e.g., fuels with different long-chain carbon and olefins) [1]. Cobalt- based FTS catalysts are one of the most relevant catalysts

for industrial applications. Controversy exists, however, regarding the role of the cobalt oxides and carbides during the reaction, more specifically, Co2C, which is the most stable carbide during the FTS reaction [2]. Some studies correlate Co2C with the deactivation of the catalyst, others with higher selectivity toward lower olefins and as intermediate species during the reaction. This work focused on the study of the formation process of cobalt carbides at relevant conditions of temperature and pressure.

This study consisted of two different in-situ experiments carried out at beamline ID20: a carburisation reaction (a control experiment) and an FTS reaction. From the control experiment, the distinct features of the Co L2,3-edges and C K-edge were obtained, as illustrated in Figure 87a