| dc.description.abstract | In this work we report the electronic properties of silicon carbide (SiC)
nanostructures, specifically, nanowires and nanoporous. It uses the methodology of first
principles "Ab-initio” by the theory of density functional by means of density functional
theory (DFT).
The nanowires and porous SiC nanostructures are modeled by means of the
supercell technique, in the case of nanoporous, columns of Si and/or C atoms are
removed along the [001] direction of a unit cell with periodic conditions, the dangling
bonds of the surface are passivated using hydrogen atoms. In the case of nanowires, also
used the supercell model, which uses a unit cell with periodic conditions in one of four
chosen directions [001] [110] [111] or [112] as well, are modeled by varying the nanowire
width. The surface of the nanowires are saturated with hydrogen atoms in order to clean
the states within the energy gap.
In the calculation of the electronic properties of nanostructures, the generalized
gradient approximation (GGA) exchange-correlation functional used is a revised version of
Perdew, Burke and Enzerhof (RPBE), the core electrons are described using ultrasoft and
norm-conserving Vanderbilt pseudopotentials.
As a result, the study of the electronic properties of SiC nanowires show a decrease
in the value of the energy band gap by increasing the diameter of the nanowires, as well
as different types of gaps observed according to the growth direction is used . In the case
of porous nanostructures, the size of the energy band gap is modified according to the
morphology and size of the supercell. | |
