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Information × Registration Number 0224U031658, 0122U001910 , R & D reports Title Nanoporous metal catalysts based on transition metals popup.stage_title Head Roik Oleksandr S., Доктор хімічних наук Registration Date 30-05-2024 Organization Taras Shevchenko National University of Kyiv popup.description2 For the first time, a study was carried out of the microstructure, morphology, and phase composition of as-quenched metal Co-Cu-Zn, Ni-Cu-Zn, Co-Ni-Cu-Zn, Fe-Co-Ni-Cu-Zn, and Mn-Fe-Co-Ni- Cu-Zn alloys (precursors), as well as porous Ni-Cu, Co-Cu, Co-Ni-Cu, Fe-Co-Ni-Cu and Fe-Co-Ni-Cu materials obtained on their basis by the method of zinc dealloying in a vacuum. The analysis showed that the hardened precursors have a complex microstructure based on several intermetallic compounds of zinc with transition metals and corresponding solid solutions. It has been established that this microstructure causes poor mechanical properties of precursors (fragility), requiring further optimization of compositions and processing methods to improve the microstructure of as-quenched ribbons. X-ray phase analysis of the resulting porous metal materials showed that they contain one or two solid solutions of 3d-transition metals with an FСС lattice coated with a zinc oxide ribbon. Studies of the morphology and microstructure of porous alloys using scanning electron microscopy and transmission electron microscopy indicate the presence of an open porous structure with pore diameters ranging from 100 to 1000 nm. A detailed analysis of the atomic structure of porous materials, carried out using high-separation transmission electron microscopy and scanning transmission electron microscopy, showed nanoscale chemical segregation in the resulting multicomponent porous materials, manifested in the formation of solid FСC solutions enriched in Co and Cu. Regions with different chemical compositions form coherent transitions, where the atomic planes of the cobalt-rich solid solution transform into the atomic planes of the copper-rich solid solution.  Product Description popup.authors Holovata Nataliia V. Kazimirov Volodymyr P. Kotova Nataliia V. Sokolskyi Volodymyr Е. Yakovenko Oleksii M. popup.nrat_date 2024-05-30 Close