| AVS 66th International Symposium & Exhibition | |
| 2D Materials | Tuesday Sessions |
| Session 2D-TuP |
| Session: | 2D Poster Session |
| Presenter: | Ziling Deng, The Ohio State University |
| Authors: | Z. Deng, The Ohio State University S.M. Mueller, The Ohio State University W. Windl, The Ohio State University J.A. Gupta, The Ohio State University |
| Correspondent: | Click to Email |
We performed density functional theory(DFT) calculation to studied the structural and electronic properties of native point defects in MoTe2. Various kinds of defects, e.g., vacancies, antisites with different charge states will be considered. With DFT, we will predict the constitutional defects with the lowest formation energies for all systems in Mo-rich, Te-rich and stoichiometric conditions as well as their dominated charge states. Additionally, the resulting output of our theoretical atomic scale model based on DFT-calculation will be used to simulate Scanning Tunneling Microscopy [https://en.wikipedia.org/wiki/Scanning_tunneling_microscope](STM) images to allow for comparison with experimental STM images. This study will provide an effective method to study the defects in MoTe2 systems, with the comparison with experiments, the results will shed new light on the defect studying in MoTe2.
MoTe2, a two-dimensional(2D) layered material has recently attracted much attention due to its excellent electronic properties. Intrinsic defects are commonly observed in MoTe2 growth, which would have a significant impact on the physical, optical, thermal, and electrical properties of the material. However, studying the atomic structure of intrinsic defects in this 2D materials is difficult since they damage quickly under the intense electron irradiation in TEM. To overcome this, we have performed a joint study between STM measurements and DFT calculations to identify the atomic structure and electronic nature of native point defects in MoTe2. We constructed analytical model from DFT and studied the structural and electronic properties of those defects. In order to understand the formation of defects and their atom-scale dynamics in MoTe2, we will use DFT to predict the constitutional defects with the lowest formation energies as well as their dominated charge states in Mo-rich, Te-rich and stoichiometric conditions to determine the necessary chemical potentials for all systems of MoTe2. Additionally, theoretically simulated STM images generated by density functional theory were used to compare with experimental STM data to enable us to assign structure of a number of defects observed during experiments.
This study provides an effective method to study the defects in MoTe2 systems by presenting results for the energetics of native point defects in MoTe2. Base on our calculation, the formation energies and charged states of the vacancies and antisites will be determined, moreover, the simulated simulated STM images allow for the identification of structural defects of MoTe2 observed in the experiment.