This is where you’ll find the freshest new brands, most exciting products and innovative launches that we think are going to make waves in the industry and in your beauty routine. This study also demonstrates that high-spatial resolution Z-contrast imaging and EELS performed simultaneously can provide unique information on the morphology and chemistry of metal species in supported metal catalysts.Beauty Rising is your go-to destination for the latest in beauty. The formation of partially oxidized copper species upon reduction at 1073K is attributed to the metallic copper interaction with the alumina support. Large spherical particles having core-shell structures with Cu(I) in the shells and Cu(0) in the cores are generated when the catalyst is reduced at 1073K. This appears to indicate that the copper has not been reduced to its metallic form due to the interaction between the copper oxide and the support. At 773K, separated Cu(I) and Cu(0) species are found existing as ring-like and bulk-like particles. Results show that the copper species are well dispersed when the catalyst is reduced below 523K.

In this paper, the microstructure of a 1wt.% Cu/γ-Al2O3 catalyst that was reduced in a 4% hydrogen/argon atmosphere at temperatures of 523, 7K, is studied by Z-contrast imaging and electron energy-loss spectroscopy (EELS) in a scanning transmission electron microscope (STEM). This work therefore brings about new observations for both a single and dual-nanocrystals system, as well as new insights in understanding the resulting dynamics behaviors. These abnormal phenomena and observations, which are fundamentally distinct from classic cases and previous reports, are mainly due to the overcharging of Au nanoparticle that produces a surface activation state in terms of high-energy plasma. Firstly, the growth process undergoes the lattice diffusion and subsequently the surface-dominated diffusion mechanism. Au nanoparticles presented the surface atomic disorder, diffusion phenomena with continuous electron-beam irradiation, and further, the long-range motion that contains mainly the three stages: charging, activation, and adjacence, which are followed by final crystal growth. Au nanocrystalline particles with sizes of 2–4 nm were prepared by a well-controlled sputtering method to stand on the BNNT surface without chemical bonding interactions. To this end, we performed an in-situ electron-beam irradiation study using transmission electron microscopy (TEM) on the Au nanocrystals that freely stand on the nitride boron nanotube (BNNT). How a heavily charged metal nanocrystal, and further a dual-nanocrystals system behavior with continuous electron charging? This refers to the electric dynamics in charged particles as well as the crystal growth for real metal particles, but it is still opening in experimental observations and interpretations. Here, the authors report direct observation of more than twenty homo and hetero-metallic compounds, including labile Ag-Cu dimers and Au-Ag-Cu trimers. The dynamic assembly and disassembly of atoms and molecules is challenging to characterize in real time, with atomic resolution and elemental identification. Even short-lived molecules with low probability of existence such as AuAg, AgCu, and AuAgCu are directly visualized as a result of identifying moving atoms at low electron doses. The video recordings of many homo- and hetero-metallic dimers are carried out by combining scanning transmission electron microscopy (STEM) with elemental identification based on the Z-contrast principle. This study directly visualizes the formation and dissociation dynamics of labile dimers and trimers at atomic resolution with elemental identification. However, recent developments in computational chemistry have placed increased importance on studying the dynamic assembly and disassembly of atoms and molecules formed in situ. Traditionally, chemistry has been developed to obtain thermodynamically stable and isolable compounds such as molecules and solids by chemical reactions.

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