X-ray studies bridge the molecular and macro length scales during the emergence of CoO assemblies.

Autor: Grote L; University of Hamburg, Institute for Nanostructure and Solid-State Physics, Center for Hybrid Nanostructures, Hamburg, Germany.; Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany., Zito CA; University of Hamburg, Institute for Nanostructure and Solid-State Physics, Center for Hybrid Nanostructures, Hamburg, Germany.; São Paulo State University UNESP, São José do Rio Preto, Brazil., Frank K; Ludwig-Maximilians-Universität München, Faculty of Physics and Center for NanoScience (CeNS), Munich, Germany., Dippel AC; Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany., Reisbeck P; Ludwig-Maximilians-Universität München, Faculty of Physics and Center for NanoScience (CeNS), Munich, Germany., Pitala K; AGH, University of Science and Technology, Faculty of Physics and Applied Computer Science, Krakow, Poland.; Academic Center for Materials and Nanotechnology, AGH University of Science and Technology, Krakow, Poland., Kvashnina KO; The Rossendorf Beamline at the European Synchrotron Radiation Facility ESRF, Grenoble, France.; Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Resource Ecology, Dresden, Germany., Bauters S; The Rossendorf Beamline at the European Synchrotron Radiation Facility ESRF, Grenoble, France.; Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Resource Ecology, Dresden, Germany., Detlefs B; European Synchrotron Radiation Facility ESRF, Grenoble, France., Ivashko O; Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany., Pandit P; Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany., Rebber M; University of Hamburg, Institute for Nanostructure and Solid-State Physics, Center for Hybrid Nanostructures, Hamburg, Germany.; The Hamburg Centre for Ultrafast Imaging, Hamburg, Germany., Harouna-Mayer SY; University of Hamburg, Institute for Nanostructure and Solid-State Physics, Center for Hybrid Nanostructures, Hamburg, Germany.; The Hamburg Centre for Ultrafast Imaging, Hamburg, Germany., Nickel B; Ludwig-Maximilians-Universität München, Faculty of Physics and Center for NanoScience (CeNS), Munich, Germany., Koziej D; University of Hamburg, Institute for Nanostructure and Solid-State Physics, Center for Hybrid Nanostructures, Hamburg, Germany. dorota.koziej@physnet.uni-hamburg.de.; The Hamburg Centre for Ultrafast Imaging, Hamburg, Germany. dorota.koziej@physnet.uni-hamburg.de.
Jazyk: angličtina
Zdroj: Nature communications [Nat Commun] 2021 Jul 20; Vol. 12 (1), pp. 4429. Date of Electronic Publication: 2021 Jul 20.
DOI: 10.1038/s41467-021-24557-z
Abstrakt: The key to fabricating complex, hierarchical materials is the control of chemical reactions at various length scales. To this end, the classical model of nucleation and growth fails to provide sufficient information. Here, we illustrate how modern X-ray spectroscopic and scattering in situ studies bridge the molecular- and macro- length scales for assemblies of polyhedrally shaped CoO nanocrystals. Utilizing high energy-resolution fluorescence-detected X-ray absorption spectroscopy, we directly access the molecular level of the nanomaterial synthesis. We reveal that initially Co(acac) 3 rapidly reduces to square-planar Co(acac) 2 and coordinates to two solvent molecules. Combining atomic pair distribution functions and small-angle X-ray scattering we observe that, unlike a classical nucleation and growth mechanism, nuclei as small as 2 nm assemble into superstructures of 20 nm. The individual nanoparticles and assemblies continue growing at a similar pace. The final spherical assemblies are smaller than 100 nm, while the nanoparticles reach a size of 6 nm and adopt various polyhedral, edgy shapes. Our work thus provides a comprehensive perspective on the emergence of nano-assemblies in solution.
(© 2021. The Author(s).)
Databáze: MEDLINE
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