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Journal of Physical Studies 23(1), Article 1301 [8 pages] (2019)
DOI: https://doi.org/10.30970/jps.23.1301 EFFECT OF THE POSITION OF AN EPOXY GROUP ON THE H-GRAPHENE CLUSTER PROPERTIES: THE DENSITY FUNCTIONAL THEORY CALCULATIONSFahimeh Shojaie
Semiconductors group, Institute of Science and High Technology and Environmental Sciences, |
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Chemical functionalization of H-graphene cluster by an epoxy group has been deemed to be an effective way to tune the electronic structure of H-graphene and open its band gap. It is important to understand the atomic structure of H-graphene oxide in order to utilize its fundamental properties and explore its potential applications. Therefore, it is essential to know the arrangement of oxygen-containing functional groups in H-graphene oxide. A computational study using DFT-based reactivity descriptors to identify favorable sites of epoxy groups on the H-graphene surface was performed in this work. Structural, electronic and optical properties of epoxy groups in various positions of the H-graphene surface were compared. All calculations were performed using DMol${}^3$ code in Materials Studio. Optical properties of epoxy groups show that the electron transmissions from HOMO to LUMO, which are related to the energy gap, have the highest wavelength and the least amount of oscillator power in all structures. The highest wavelength, which occurs in the transmission H$\to$L (1512 nm), is related to structure 10. This is consistent with the results of the energy gap and global softness. The energy of interactions is negative in all structures, which indicates that the interaction between the oxygen atom and H-graphene, which results in the formation of H-graphene epoxy, is exothermic. The number of electron occupancy states in the energy levels between HOMO and LUMO has changed for oxygen-absorbed H-graphene, which indicates the effect of oxygen on the H-graphene surface.
Supplementary for this paper is available at https://doi.org/10.30970/jps.23.1301sm
PACS number(s): 31.15.A-