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arXiv · 1910.09836

Environmental Effects on the Charge Transfer Properties of Graphene Quantum Dot Based Interfaces

Silvio Osella·Stefan Knippenberg
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Abstract

Graphene quantum dots (GQD) are interesting materials due to the confined sizes which allow to exploit their optoelectronic properties, especially when they interface with organic molecules through physisorption. In particular, when interfaces are formed, charge transfer (CT) processes can occur, in which electrons can flow either from the GQD to the absorbed molecule, or vice versa. These processes are accessible by modelling and computational analysis. Yet, the presence of different environments can strongly affect the outcome of such simulations which, in turn, can lead to wrong results if not taken into account. In the present multiscale study, we assess the sensibility of the computational approach and compute the CT, calculated at interfaces composed by GQD and amino-acene derivatives. The hole transfer is strongly affected by dynamic disorder and the nature of the environment, and imposes stringent descriptions of the modelled systems to ensure enhanced accuracy of the transfer of charges.

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Silvio Osella, Stefan Knippenberg. 2019-10-22. Environmental Effects on the Charge Transfer Properties of Graphene Quantum Dot Based Interfaces. https://doi.org/10.1002/qua.25882

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