Silicene and germanene: Silicon and germanium in the flatland
Free-standing buckled silicene and germanene are predicted to be stable. 44 Silicene/Ag(111): evidence for a 2D hybrid surface metallic band, as in graphene. Evidence of Dirac bands in multilayer silicene with ( 3  3 ) R 30  superstructure. Promising progress in the growth of stable epitaxial germanene. 2D hexagonal AlN is a non-metallic candidate substrate for silicene and germanene.
silicene germanene 2d hexagonal aln 2d materials valence band structure hybrid surface band