3 research outputs found
Towards a Better Understanding of the Genetic and Physiological Basis for Nitrogen Use Efficiency in Maize
Structural and Morphological Description of Sn/SnO<sub><i>x</i></sub> CoreāShell Nanoparticles Synthesized and Isolated from Ionic Liquid
The potential application of high
capacity Sn-based electrode materials
for energy storage, particularly in rechargeable batteries, has led
to extensive research activities. In this scope, the development of
an innovative synthesis route allowing to downsize particles to the
nanoscale is of particular interest owing to the ability of such nanomaterial
to better accommodate volume changes upon electrochemical reactions.
Here, we report on the use of room temperature ionic liquid (i.e.,
[EMIm<sup>+</sup>]Ā[TFSI<sup>ā</sup>]) as solvent, template,
and stabilizer for Sn-based nanoparticles. In such a media, we observed,
using Cryo-TEM, that pure Sn nanoparticles can be stabilized. Further
washing steps are, however, mandatory to remove residual ionic liquid.
It is shown that the washing steps are accompanied by the partial
oxidation of the surface, leading to a coreāshell structured
Sn/SnO<sub><i>x</i></sub> composite. To understand the structural
features of such a complex architecture, HRTEM, MoĢssbauer spectroscopy,
and the pair distribution function were employed to reveal a crystallized
Ī²-Sn core and a SnO and SnO<sub>2</sub> amorphous shell. The
proportion of oxidized phases increases with the final washing step
with water, which appeared necessary to remove not only salts but
also the final surface impurities made of the cationic moieties of
the ionic liquid. This work highlights the strong oxidation reactivity
of Sn-based nanoparticles, which needs to be taken into account when
evaluating their electrochemical properties