Εξειδίκευση τύπου :	Ανακοίνωση σε συνέδριο
Τίτλος:	Molecularly pillared graphene with dithiolene and diamine linking groups
Δημιουργός/Συγγραφέας:	Papasouli, Emilia Lingas, Rafael Skarmoutsos, Ioannis [EL] Κλώντζας, Εμμανουήλ[EN] Klontzas, Emmanuel Koukaras, Emmanouil
Ημερομηνία:	2021-03-19
Γλώσσα:	Αγγλικά
ISSN:	2668-6384
Περίληψη:	Molecularly pillared graphene (MPG) is a class of 3D layered materials composed by graphene layers and interconnected via organic molecules (called molecular pillars) through covalent bonding. The combination of different molecular pillars with various chemical composition, size and rigidity, together with different pillar densities and functional groups leads to great prospects in controlling their electromechanical properties for specific applications [1-5]. The aim of this computational study is the investigation of the diversity of the structural and electromechanical properties of MPGs when different functional groups are incorporated to create the covalent bonding with the graphene layers. The study has been performed employing periodic boundary conditions within the frameworks of density functional (DFT) and tight binding (TB) levels of theory. Two MPG models have been designed with amine and thiol crosslinking functionalities and we compare the effect of this chemical modification on their structural and electronic properties. The computations were performed for unit cells of bilayer graphene with 72 carbon atoms per layer interconnected with 1,4-benzenediamine and 1,4-benzenedithiol, respectively (1 linker per layer), as shown in Fig. 1. Initially, we optimized the structures of molecular linkers linked to circumcoronene using the PBE functional [6] with the Gaussian package [7]. Subsequently, we performed geometry and cell optimizations simultaneously, by employing different computational methods in order to compare the obtained results: initial optimization was performed with the GFN1-xTB [8,9] method using the CP2K code [10]. The resulting structures were re-optimized within the gradient corrected (GGA) functional PBE using the Quantum Espresso package [11]. Then, the computations were repeated by including Grimme’s dispersion correction D3. The Density of states (DOS) of the final optimized geometries were examined in all cases. All DOS computations were performed with the Quantum Espresso package. Our study shows that these structures present different structural characteristics, provided in Table 1. The DOS diagrams reveal that MPG with 1,4-benzenediamine exhibits a larger band gap than the MPG with 1,4-benzenedithiol (shown in Fig. 2). Therefore, by using different functional groups we can achieve different electronic properties for the MPGs.
Όνομα εκδήλωσης:	35th Panhellenic Conference on Solid State Physics and Materials Science
Ημ/νία έναρξης εκδήλωσης :	2021-09-26
Ημ/νία λήξης εκδήλωσης :	2021-09-29
Τόπος εκδήλωσης:	Αθήνα (Ελλάδα)
Τίτλος πηγής δημοσίευσης:	Proceedings International
Τόμος/Κεφάλαιο:	3
Τεύχος:	3
Σελίδες:	27-28
Θεματική Κατηγορία:	[EL] Φυσική και θεωρητική χημεία[EN] Physical and theoretical chemistry
Λέξεις-Κλειδιά:	Functionalized graphene Molecularly pillared graphene Graphene oxide Density Functional theory Tight binding Electronic properties Mechanical properties
EU Grant identifier:	No 1536
Κάτοχος πνευματικών δικαιωμάτων:	© 2021 by the authors
Όροι και προϋποθέσεις δικαιωμάτων:	This article is an open-access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Ηλεκτρονική διεύθυνση περιοδικού (link) :	https://conferenceproceedings.international/
Σημειώσεις:	This project has received funding from the Hellenic Foundation for Research and Innovation (HFRI) and the General Secretariat for Research and Innovation (GSRI) under grant agreement No 1536.
Εμφανίζεται στις συλλογές:	Ινστιτούτο Θεωρητικής και Φυσικής Χημείας (ΙΘΦΧ) - Επιστημονικό έργο