Connecting Atomic-scale Impurities to Larger Morphologies

Nadire Nayir

Karamanoglu Mehmetbey University/The Pennsylvania State University

(Half) van der Waals epitaxy of single-crystal two-dimensional (2D) materials (e.g., TMD, h-BN, graphene, group III materials) on substrates are quite challenging and time and source expensive. Therefore, theoretically characterization of materials is essential to deepen our understanding of the physical and chemical properties of materials, thus, ensuring the highest quality in the design and manufacturing processes of materials.
This talk will first focus on our multiscale modeling efforts for the synthesis and characterization of 2D materials. I will show some of our own results which have been dedicated to addressing the major challenges encountered in experiments such as (i) unidirectional alignment of 2D domains on a substrate, (ii) impact of the surface chemistry and crystallographic structure of a substrate on the van der Waals epitaxy, (iii) unraveling gas-phase chemistry in chemical vapor deposition environment, (iv) impact of growth conditions on the crystal structure of 2D materials. Additionally, since technology is developing faster than ever before, and increasingly depends on constantly advancing basic research and expanding scientific knowledge, an effective-force field development for multicomponent systems has become crucial to accelerate the knowledge transfer to industry. In the second part, this talk will also provide an overview of the ReaxFF force fields and multiscale model framework that we developed for 2D materials [4-6]. These potentials offer a computationally cost-effective and versatile research tool for the materials science community to study large-scale simulations of synthesis and defect-, phase-, strain-, and edge engineering of a material of interest, paving the way for increased application of atomic-level modeling of 2D materials. In turn, new computational materials and new knowledge will benefit the society by advancing new technologies in energy conversion, storage, and other important areas.

1. N. Nayir, M. Y. Sengul, A. L. Costine, P. Reinke, S. Rajabpour, A. Bansal, A. Kozhakhmetov, J. Robinson, J. M. Redwing, A. van Duin, “Atomic-scale probing of defect-assisted Ga intercalation through graphene using ReaxFF Molecular Dynamics Simulations”, Carbon, 190, 276–290 (2022)
2. DR Hickey, N Nayir, M Chubarov, TH Choudhury, S Bachu, L Miao, Y. Wang, C. Qian, V. H. Crespi, J. M. Redwing, A. C. T. van Duin, N. Alem “Illuminating Invisible Grain Boundaries in Coalesced Single-Orientation WS2 Monolayer Films”, Nano Letters 21 (15), 6487-6495 (2021)
3. N. Briggs, B. Bersch, Y. Wang, J. Jiang, R. J. Koch, N. Nayir, K. Wang, M. Kolmer, W. Ko, A. D. L. F. Duran, S. Subramanian, C. Dong, J. Shallenberger, M. Fu, Q. Zou, Y. Chuang, Z. Gai, A. Li, A. Bostwick, C. Jozwiak, C. Chang, E. Rotenberg, J. Zhu, A. C. T. van Duin, V. Crespi, J. A. Robinson, “Atomically thin half-van der Waals metals enabled by confinement heteroepitaxy”, Nature Materials 19 (6), 637-643 (2020) 4. N. Nayir, Y. K. Shin, Y. Wang, M. Y. Sengul, D. Reifsnyder Hickey, M. Chubarov, T. H Choudhury, N. Alem, J. Redwing, V. H Crespi, A. CT van Duin, “A ReaxFF Force Field for 2D-WS2 and Its Interaction with Sapphire”, The Journal of Physical Chemistry C 125 (32), 17950-17961 (2021) 5. N. Nayir, Y. Wang, Y. Ji, T. Choudhury, J. M. Redwing, L.-Q. Chen, V. H. Crespi, A. C. T. van Duin, “Theoretical Modeling of Edge-controlled Growth Kinetics and Structural Engineering of 2D-MoSe2”, Materials Science and Engineering: B 271, 115263 (2021)
6. Y. Xuan, A. Jain, S. Zafar, R. Lotfi, N. Nayir, Y. Wang, T. H. Choudhury, S. Wright, J. Feraca, L. Rosenbaum, J. M. Redwing, V. Crespi, A. C. T. van Duin, “Multi-scale modeling of gas-phase reactions in metal-organic chemical vapor deposition growth of WSe2”, Journal of Crystal Growth 527, 125247 (2019)

About The Speaker

Nadire Nayir is currently a postdoctoral research associate of Physics at Karamanoglu Mehmetbey University and a research affiliate of the 2-dimensional Crystal Consortium (2DCC) at The Pennsylvania State University. She received her BS in physics education from Selcuk University in 2009, and Ph.D. in computational physics from Middle East Technical University in 2018. She worked as a postdoctoral associate of Mechanical Engineering at The Pennsylvania State University for 3 years.

Join Zoom Meeting
https://zoom.us/j/5876884794?pwd=OUNFRTZKZDNRMm5MWjJjSlhnMXFNUT09https://zoom.us/j/95581724217