We study the effects of N2 partial pressures, growth temperatures, and precursors ratios and energies on the growth modes of transition-metal nitride and carbide thin films via classical and DFT-based ab initio molecular dynamics (AIMD) simulations. We probe the effects of deposition parameters on competitive growth and identify representative grain boundary configurations in TM nitride polycrystals.
In parallel, we combine experiments and lattice-dynamics ab initio simulations to investigate the effects of lattice vibrations on transition-metal nitride phase-stability, mechanical properties, and thermal conductivity. We also use AIMD simulations to investigate the catalytic properties of TM nitride and carbide surfaces. Applications include water, oxygen, CO2, and H2 splitting for renewable energy and sustainable environment applications.
Using SNIC resources, during last year we have published 7 papers in peer-reviewed journals. SNIC resources have been acknowledged. Other 5 manuscripts are under consideration for publication: one in New Journal of Physics, three in Acta Materialia, and one in Applied Surface Science
1. D. Edstrom, D.G. Sangiovanni, L. Hultman, V. Chirita, I. Petrov, J.E. Greene
Journal of Applied Physics 121 (2017) 025302
Effects of incident N atom kinetic energy on TiN/TiN(001) film growth dynamics: A molecular dynamics investigation
2. M. Mikula, D.G. Sangiovanni, et al.
Thermally induced age hardening in tough Ta-Al-N coatings via spinodal decomposition
Journal of Applied Physics 121, 155304 (2017)
3. M. Mikula, M. Truchlý, D.G. Sangiovanni, et al.
Experimental and computational studies on toughness enhancement in Ti-Al-Ta-N quaternaries
Journal of Vacuum Science & Technology A 35, 060602 (2017)
4. D. Gambino, D.G. Sangiovanni, et al.
Nonequilibrium ab initio molecular dynamics determination of Ti monovacancy migration rates in B1 TiN
Physical Review B 96, 104306 (2017)
5. Q. Zheng, A.B. Mei, M. Tuteja, D.G. Sangiovanni, L. Hultman, I. Petrov, J.E. Greene
Phonon and electron contributions to the thermal conductivity of VNx epitaxial layers
Physical Review Materials 1, 065002 (2017)
6. D. Edström, D.G. Sangiovanni, L. Hultman, I. Petrov, J.E. Greene, V. Chirita
Elastic properties and plastic deformation of TiC- and VC-based pseudobinary alloys
Acta Materialia 144, 376 (2018)
7. D.G. Sangiovanni, A.B. Mei, D. Edström, L. Hultman, V. Chirita, I. Petrov, J.E. Greene
Effects of surface vibrations on interlayer mass transport: Ab initio molecular dynamics investigation of Ti adatom descent pathways and rates from TiN/TiN(001) islands
Physical Review B 97, 035406 (2018)