SAIP2015

Prediction of Structures and Energy stabilities of VO₂ nanoparticles.

30 Jun 2015, 16:10

1h 50m

Board: A.325

Poster Presentation Track A - Division for Physics of Condensed Matter and Materials Poster1

Speaker

Mr Makondelele Netsianda (University of Limpopo)

Level for award<br>&nbsp;(Hons, MSc, <br> &nbsp; PhD, N/A)?

PhD

Apply to be<br> considered for a student <br> &nbsp; award (Yes / No)?

No

Would you like to <br> submit a short paper <br> for the Conference <br> Proceedings (Yes / No)?

No

Abstract content <br> &nbsp; (Max 300 words)<br><a href="http://events.saip.org.za/getFile.py/access?resId=0&materialId=0&confId=34" target="_blank">Formatting &<br>Special chars</a>

We have employed a Genetic Algorithm (GA) Hybrid technique as implemented in GULP code to predict the ground-state energies of various small V_nO_2n nanoparticles (n = 1-15). The search procedures were based on the GA techniques and the Interatomic Potential (IP) model, and did not refer to any known VO₂ polymorphs. All stable structures were optimized using Density Functional Theory (DFT) employing Dmol code. More importantly, ground state VO₂ nanoparticles (clusters n = 1-3), were identified. The results showed that for n = 1 (VO₂), the energies of both the core and shell candidate structures were found to be similar. As n increases, the symmetry changed from D2h to C2v and the structures became more stable. Interestingly, their atomic arrangements were also observed to be similar to those of TiO₂. Furthermore, the O-V-O bond angles for both the core and shell models (111.2o) compare well with those for titania (111.4o).

Main supervisor (name and email)<br>and his / her institution

Phuti Ngoepe phuti.ngoepe@ul.ac.za University of Limpopo

Please indicate whether<br>this abstract may be<br>published online<br>(Yes / No)

No