  Considerably different properties emerge in nanomaterials as a result of
quantum confinement and edge effects. In this study, the electronic and
magnetic properties of quasi zero dimensional silicene nanoflakes (SiNFs) are
investigated using first principles calculations. Whilst the zigzag edged
hexagonal SiNFs exhibit nonmagnetic semiconducting character, the zigzag edged
triangular SiNFs are magnetic semiconductors. One effective method of
harnessing the properties of silicene is hydrogenation owing to its
reversibility and controllability. From bare SiNFs to half hydrogenated and
then to fully hydrogenated, a triangular SiNF experiences a change from
ferrimagnetic to very strong ferromagnetic, and then to non-magnetic.
Nonetheless, a hexagonal SiNF undergoes a transfer from nonmagnetic to very
strong ferromagnetic, then to nonmagnetic. The half hydrogenated SiNFs produce
a large spin moment that is directly proportional to the square of the flakes
size. It has been revealed that the strong induced spin magnetizations align
parallel and demonstrates a collective character by large range ferromagnetic
exchange coupling, giving rise to its potential use in spintronic circuit
devices. Spin switch models are offered as an example of one of the potential
applications of SiNFs in tuning the transport properties by controlling the
hydrogen coverage.
