INVESTIGADORES
AMBRUSI Ruben Eduardo
artículos
Título:
DFT study of Rh and Ti dimers decorating N-doped pyridinic and pyrrolic graphene for molecular and dissociative hydrogen adsorption
Autor/es:
AMBRUSI, RUBÉN E.; PRONSATO, MARÍA E.
Revista:
APPLIED SURFACE SCIENCE
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Año: 2019
ISSN:
0169-4332
Resumen:
A theoretical study using density functional theory was employed to analyze thehydrogen adsorption on Rh2 and Ti2 dimers decorating pyridine and pyrrolic-likenitrogen doped graphene. First, an analysis of geometry, stability, projected density ofstates, overlap population and charge distribution was performed to understand theinteraction between Rh and Ti metal adatoms and dimers with pyridinic and pyrrolicgraphene. Charge transfer occurs from metal to substrate in all cases. An investigationof H2 adsorption on Rh and Ti metals dimers on pyridinic and pyrrolic N-dopedgraphene was also performed. Molecular adsorption states were observed for Ti onpyridinic graphene and for Rh on both substrates. H2 dissociative adsorption occurs onboth metal supported dimers. H2 s states hybridize with the Rh and Ti d band, forminglocalized and dispersed states in concordance with the mechanisms observed for H2adsorption. The activation energies were calculated obtaining values smaller than 0.59eV, indicating that the dissociation of H2 can occur spontaneously at room temperature.HSE06 hybrid functional was used to test the accuracy of PBE-D2 functional in theactivation energy calculation. Adsorption in the molecular states occurs with nobarriers.
