Relative stability of nanosized β-C3N4 and graphitic C3N4 from first principles calculations

Relative stability of nanosized β-C3N4 and graphitic C3N4 has been studied by using first principles calculations. It has been demonstrated that the relative stability sequence changes with increasing size of the nanostructure. When the number of C3N4 molecules in the C3N4 nanostructure is less than a threshold number, the β-C3N4 nanostructure is in the stability phase. When the number of C3N4 molecules in the C3N4 nanostructure exceeds the threshold number, the graphitic C3N4 is in the stability phase. In addition, size-dependence electronic properties of β-C3N4 and graphitic C3N4 nanostructures have also been analyzed in this work.