Modeling Studies on Uptake of Hydrogen Molecule by Graphene

초록

Over the past few decades, there has been extensive research to seek a solution for the issue of global warming caused from use of fossil fuels. One of the most challenging studies in this realm would be the development on exploitable hydrogen energy, since the hydrogen could be used as a clean and recyclable energy source in fuel cell [1]. In this work, to investigate the physisorption properties more accurately, detailed first-principle and DFT calculations [2] on the interactions of molecular hydrogen, H2, on various poly-aromatic hydrocarbons (PAHs) as model systems for graphene sheets have been carried out. Physisorption of gases on some carbon nanomaterials has been modeled and theoretically treated earlier [3]. The two-layered ONIOM approach implemented in the Gaussian 03 and 09 packages was used due to the size of the system. The unit-cell approach in the Dmol3 was used for n x n unit cell (n=1, 2, … , 8) and hydrogen molecules on the graphene sheets. Physisorption orientations were also investigated to find some favorable structures. The GGA (generalized gradient approximation) calculations were performed using the Perdew-Burke- Ernzerhof function, including the Grimme dispersion correction term [4].