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Abstract
Fuel cells are an attractive option for renewable energy that utilize the transfer of chemical energy to generate electrical energy. Fuel cell efficiency is dependent on the quality of the electrocatalyst and traditional noble metal electrocatalysts, in addition to being expensive, have reached a limit in progress. Monolayer transition metal dichalcogenides (TMDCs) have been proposed as a substitute because of their lower price and recent successes1 as catalysts. In order to guide further attempts to optimize TMDCs for catalytic activity, we have examined the electronic properties of pure and alloyed TMDC with transition-metal terminated edge sites. Ribbon- and flake-based structures are compared to determine which geometry accurately represents physical edges observed experimentally. Despite the instability of TM edges in flakes and the dipole of non-centrosymmetric ribbons, edge-electronic descriptors like d-band center and the number of electrons near the Fermi level are shown to exhibit consistent relations between different TMDCs independent of geometry. Finally, it was decided that the flake structure is currently more viable than the ribbon structure due to the ribbon having an internal gradient of the electrostatic potential.
Document Type
Final Report
Class Name
Mechanical Engineering and Material Sciences Independent Study
Date of Submission
1-11-2019
Recommended Citation
Beukelman, Andrew; Mishra, Rohan; and Cavin, John, "First-principles Investigation of the Electronic Structure of Metal-Terminated Edges of Two-Dimensional Transition Metal Dichalcogenide Alloys" (2019). Mechanical Engineering and Materials Science Independent Study. 84.
https://openscholarship.wustl.edu/mems500/84