Synthesis of BI2O3/SiO2 core–shell nanoparticles by an atmospheric CVS/CVD process and their modification by hydrogen or electron-beam induced reduction

Nanoscale thermodynamics and kinetics were explored via the manipulation of Pb/PbO core-shell nanoparticles with a focused electron beam which served as a nanometer heating probe. In the electron transmission microscope (TEM), when an electron beam of moderate intensity was used to irradiate the nanoparticles, the amorphous particles gradually crystallized and showed distinct boundaries between lead cores and oxide shells. In such a way, the oxide shell could be easily measured to be 0.5-2 nanometers. With a high intensity electron beam, melting of the lead cores could be observed, indicating a sufficient local temperature increasing induced by the concentrated heat generated by inelastic electron collisions. The fluidic metal core erupted out through the cracked shells accompanied with the vanish of the boundaries between the cores and shells. Manipulations on nanoparticle decorated carbon wires proved that the lead oxide shells could sustain the irradiation of intense electron beam.

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Mechanism of Electron Beam Induced Oxide Layer Thickening on Iron–Iron Oxide Core–Shell Nanoparticles

The Journal of Physical Chemistry C ◽

10.1021/acs.jpcc.5b00943 ◽

2015 ◽

Vol 119 (15) ◽

pp. 8357-8363 ◽

Cited By ~ 10

Author(s):

Jennifer A. Sundararajan ◽

Maninder Kaur ◽

You Qiang

Keyword(s):

Electron Beam ◽

Iron Oxide ◽

Oxide Layer ◽

Core Shell ◽

Shell Nanoparticles ◽

Iron Iron ◽

Iron Oxide Core ◽

Core Shell Nanoparticles

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Structure and mechanism of the formation of core–shell nanoparticles obtained through a one-step gas-phase synthesis by electron beam evaporation

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.6.89 ◽

2015 ◽

Vol 6 ◽

pp. 874-880 ◽

Cited By ~ 28

Author(s):

Andrey V Nomoev ◽

Sergey P Bardakhanov ◽

Makoto Schreiber ◽

Dashima G Bazarova ◽

Nikolai A Romanov ◽

...

Keyword(s):

Electron Beam ◽

Electron Beam Evaporation ◽

Core Shell ◽

Shell Nanoparticles ◽

Factors Affecting ◽

Vapour Concentration ◽

Si Nanoparticles ◽

Mechanisms Of Formation ◽

One Step ◽

Core Shell Nanoparticles

The structure of core–shell Cu@silica and Ag@Si nanoparticles obtained in one-step through evaporation of elemental precursors by a high-powered electron beam are investigated. The structure of the core and shell of the particles are investigated in order to elucidate their mechanisms of formation and factors affecting the synthesis. It is proposed that the formation of Cu@silica particles is mainly driven by surface tension differences between Cu and Si while the formation of Ag@Si particles is mainly driven by differences in the vapour concentration of the two components.

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