Estudio teórico de la disociación de hidrógeno molecular en un modelo de nanotubo de carbono solo y modificado, empleando DFT

Abstract

Abstract:This paper presents the theoretical study of molecular hydrogen dissociation in models of single and double-walled nanotubes, modified with a nickel cluster, using computer programs. The systems used were built using the Materials Studio 4.4 program. The single-walled nanotube has an internal diameter of 13,75 Å and in the double-walled nanotube the central tube is 9,74 Å in diameter. It was tested with clusters of 10 and 13 atoms and finally it was decided to work with the 13 atoms, since it has been the most used in previous research. A calculation method based on the DFT and the functional PBE was used within the conjugate gradient approximation implemented in the VASP program. By means of which it was obtained that the dissociation energy of H2 under vacuum is 4,53 eV, in the unmodified nanotube it is 3,61 eV; as in the nanotube it doesn t dissociate spontaneously, dissociation is carried out in a nickel cluster, obtaining an exothermic energy of -0,46 eV.