TY - GEN
TI - AB INITIO STUDY OF SILVER NANOPARTICLES, GRAIN BOUNDARIES AND THEIR \nQUADRUPLE JUNCTIONS
T3 - NANOCON 2021 - International Conference on Nanomaterials - Research and Application /13./
AU - Polsterová, S.
AB - Motivated by our experimental research related to silver nanoparticles with various morphologies, we have employed quantum-mechanical calculations to provide our experiments with theoretical insight. We have computed properties of a 181-atom decahedral silver nanoparticle and two types of internal extended defects, -5(210) grain boundaries (GBs) and quadruple junctions (QJs) of these GBs. We have employed a supercell approach with periodic boundary conditions. Regarding the thermodynamic stability of the decahedral nanoparticle, its energy is higher than that of a defect-free face-centered cubic (fcc) Ag by 0.34 eV/atom. As far as the -5(210) GB is concerned, its energy amounts to 0.7 J/m2 and we predict that the studied GBs would locally expand the volume of the lattice. Importantly, the system with GBs is found rather close to the limit of mechanical stability. In particular, the computed value of the shear-related elastic constant C66 is as low as 9.4 GPa with the zero/negative value representing a mechanically unstable system. We thus predict that the -5(210) GBs may be prone to failure due to specific shearing deformation modes. The studied GBs have also the value of Poisson’s ratio for some loading directions close to zero. Next, we compare our results related solely to -5(210) GBs with those of a system where multiple intersecting -5(210) GBs form a network of quadruple junctions. The value of the critical elastic constant C66 is higher in this case, 13 GPa, and the mechanical stability is, therefore, better in the system with QJs.
SN - 2694-930X
SN - 978-80-88365-00-6
UR - http://www.nusl.cz/ntk/nusl-511543
UR - https://hdl.handle.net/11104/0335527
A2 - Pizúrová, Naděžda
A2 - Všianská, Monika
A2 - Sokovnin, S.
A2 - Šob, Mojmír
A2 - Friák, Martin
LA - eng
KW - Grain boundaries
KW - Nanoparticles
KW - Elasticity
KW - Junctions
PY - 2022
PB - Ústav fyziky materiálů, Žižkova 22, 616 62 Brno, http://www.ipm.cz/
ER -