2D Materials – Preparation, Properties & Applications: Modeling & Simulations I
Sponsored by: TMS Functional Materials Division, TMS: Thin Films and Interfaces Committee
Program Organizers: Nuggehalli Ravindra, New Jersey Institute of Technology; Ramana Chintalapalle, University of Texas at El Paso; Gerald Ferblantier, University of Strasbourg - IUT LP / ICube Laboratory - CNRS; Sufian Abedrabbo, Khalifa University; Amber Shrivastava, Indian Institute of Technology Bombay
Tuesday 2:00 PM
March 16, 2021
Room: RM 11
Location: TMS2021 Virtual
Session Chair: Gerald Ferblantier, University of Strasbourg; Sufian Abedrabbo, Khalifa University
2:00 PM
Computational Synthesis of 2D Materials: A High-throughput Approach to Materials Design: Tara Boland1; Arunima Singh1; 1Arizona State University
The emergence of two-dimensional materials opened up many potential avenues for novel device applications such as nanoelectronics, topological insulators, field-effect transistors, microwave, and terahertz photonics, and many more. To date, there are over 1,000 theoretically predicted 2D materials. However, only 55 2D materials have been experimentally synthesized. Computational methods such as density functional theory can be used to determine the suitable substrates to synthesize as-yet-hypothetical 2D materials. Using various 2D materials databases and van der Waals corrected density functional theory we investigate the suitability of metallic, cubic-structured substrates to stabilize 2D growth. For materials which meet the criteria for suitable substrate-assisted synthesis methods such as chemical vapor deposition, the density of states is computed to characterize the electronic properties of these materials for device applications.
2:20 PM Invited
Assessment of Gas Sensing Properties of 2D Materials by Comprehensive Density Functional Theory Calculations: Siby Thomas1; Mohsen Asle Zaeem1; 1Colorado School of Mines
This work presents a comprehensive and transferrable computational framework based on density functional theory (DFT) calculations to provide new insights on gas sensing properties of two-dimensional (2D) Materials. By offering quantitative understanding of chemical bonding, electronic properties, and charge transfer in 2D materials, this framework is a valuable tool for determining surface-adsorbate interactions in different class of 2D materials. To show the capabilities and transferability of this framework, we investigate the gas sensing properties of a newly designed boron-phosphorus monolayer (BP-ML) as well as the pristine and defective monolayer Ti2CX2 (X=F-, O-, OH-) MXenes by analyzing the adsorption energy, charge transfer, and electronic properties of different atmospheric toxic gas molecules (N2O, NO2, NH3, NO, CO2, SO2, CO, COCl2) adsorbed on this 2D materials. Results show a semimetal to metal transition in the case of adsorption of NO2 on BP-ML and strong physisorption of all molecules on both BP-ML and MXenes.
2:45 PM Invited
Computational Modeling of Two-Dimensional Materials for Sustainable Energy Storage: Dibakar Datta1; 1New Jersey Institute of Technology
2D materials and their heterostructures are promising energy materials. Two important computational aspects of 2DM-based batteries are addressed – (i) 2DM anode materials, and (ii) 2DM as van der Waals (vdW) slippery interface. The conventional anode materials have several problems - low gravimetric, high volume expansion, etc. We show that topologically modified 2DM (e.g., porous graphene) can be utilized as high-capacity anode materials (e.g., Li, Na, Ca-ion batteries). However, several challenges need to be addressed - trapping of adatoms at the defect sites, mechanical degradation, etc. The second part of the presentation discusses the interface of anode and current-collector (e.g., silicon anode and copper current-collector in Li-ion battery). We propose the usage of the graphene layer over the current collector as a vdW slippery interface to combat the issue of high-stress development at the anode-current collector interface during charging/discharging. Our computational results are in excellent agreement with the experimental findings.
3:10 PM Invited
Thermal Laser Assisted Manufacturing of Two-dimensional Atomic Layers Heterostructures: Yingtao Wang1; Annie Xian Zhang1; 1Stevens Institute of Technology
Following the interest in graphene since its first isolation by mechanical exfoliation in 2004, the broader family of two dimensional (2D) materials has been the subject of extensive attention thanks to their unique properties and atomically thin structure. In particular, transition metal dichalcogenides (TMDC) materials have shown unique optical and electrical properties, such as band structure transitions, semiconducting transport behavior, and strong photoluminescence, which are distinct from those of graphene and other carbon allotropes. TMDC materials are also intriguing for optical, electrical, and thermoelectric applications, especially in few-layer forms. Energy transport properties of TMDC materials have been receiving increasing interest due to the increased energy dissipation needs resulted from the Moore’s law bottleneck. In this talk, thermal transport properties of 2D materials (with focus on TMDC materials) will be introduced in the aspects of background, current development, and Dr. Zhang’s research in studying various thermal properties of 2D materials.
3:35 PM Invited
Energetics and Electronic Properties of Dopants and Defect Complexes in 2D Transition Metal Dichalcogenides from First-principles: Anne Marie Tan1; Christoph Freysoldt2; Richard Hennig1; 1University of Florida; 2Max-Planck-Institut f ̈ur Eisenforschung GmbH
Two-dimensional (2D) semiconducting transition metal dichalcogenides (TMDCs) have attracted extensive research interests for potential applications in optoelectronics, spintronics, photovoltaics, and catalysis. A detailed understanding of how defects, dopants, and impurities control the electronic and optical properties of 2D TMDCs is necessary to fully realize their potential for these applications. We perform density functional theory calculations to accurately compute formation energies, charge transition levels, and electronic properties of dopants, defects, and complexes in a range of technologically important TMDCs. We utilize a correction scheme to ensure the appropriate electrostatic boundary conditions for charged defects in 2D materials and investigate the dependence of computed defect properties on different levels of theory, including spin-orbit coupling where required. We identify dopants which can bind with intrinsic defects to form complexes, passivating the dopants, thus rendering them less effective. We also demonstrate how theoretical predictions can help inform the interpretation of experimental results.
4:00 PM Invited
Stabilization of a Ferroelectric Phase in Two Dimensional MXene Monolayers: Joshua Young1; Mo Li1; Olamide Omisakin1; 1New Jersey Institute of Technology
Two dimensional ferroelectric materials, which display switchable spontaneous electric polarizations at the monolayer limit, are gaining attention as components for ultrathin electronic devices; however, those with out-of-plane polarizations are challenging to find. Recently, an oxygen-functionalized Sc2C MXene (Sc2CO2) was postulated to exhibit such a phase as a metastable state.[1] In this work, we used density functional theory calculations to investigate a series of other M2CX2 materials. First, we found that the ferroelectric phase can be made the most energetically stable state via chemical substitution of Sc with Y and/or O with F. Moreover, the polarization and band gap can be systematically tuned through such substitution. Finally, these properties can also be enhanced by the application of external strain or by alloying. These findings demonstrate that such methods are powerful ways to stabilize and control low dimensional ferroelectric materials.[1] Chandrasekaran et al., Nano Letters 17 3290 (2017)
4:25 PM Invited
Tracking Structural Flexibility and Dynamics in 2D Metal-Organic Frameworks and their Effects on Electrical Conductivity and Catalytic Activity: Farnaz Shakib1; Mohammad Momeni1; 1New Jersey Institute of Technology
Two-dimensional (2D) conductive metal-organic frameworks (MOFs) are a unique class of porous materials which offer electrical conductivity along with large surface area and penetrability for targeted analytes. In spite of these merits, engineering of targeted structure-property relationships in 2D MOFs remains a challenge due to limited fundamental understanding of intrinsic MOF structure and its electronic properties, as well as effects of humidity and confined water dynamics on their stability and electrical conductivity. To tame the flexible and ever-changing layered structures of 2D MOFs, we develop ab initio parametrized force fields that allow large-scale/long-time simulations of the dynamics of both dry and hydrated MOFs. Our molecular dynamics simulations reveal the structural reasons behind hydrolysis of Co3(HHTP)2 vs. intact Cu3(HHTP)2, HHTP=2,3,6,7,10,11-hexahydroxytriphenylene, elucidate the effects of temperature and humidity-induced structural deformations and heterogeneity on catalytic activity of Co3(HTTP)2, HTTP=hexathiotriphenylene, and answer the long-posed question of the nature of electrical conductivity in Ni3(HITP)2, HITP=2,3,6,7,10,11-hexaiminotriphenylene.