Unveiling bandgap behavior of chiral carbon nitride nanotubes.

In recent years, Carbon nitride (C x N y) materials have garnered attention due to their high potential for usage in photoelectric catalysis, fuel cells, and electronic devices. Meanwhile, carbon nitride nanotubes (C x N y NTs) are viable contenders for various applications. Thus far, the majority of research on C x N y NTs has centered around the zigzag and armchair-like C x N y NTs, while rather little on chiral nanotubes. To comprehensively understand chiral C x N y NTs, a range of C x N y NTs with (n ,0), (n , n) and chiral (n , m) were created, including C 3 N 4 NTs, g-C 3 N 4 NTs, C 3 NNTs, g-CNNTs, and C 2 NNTs. Density functional tight binding calculations demonstrates that all C 3 N 4 NTs, g-C 3 N 4 NTs and g-CNNTs are semiconductors with exceedingly high band gap (E g) values (>2.5 eV), while C 2 NNTs and C 3 NNTs display moderate band gaps (<2.0 eV). Meanwhile, the bandgap of C 3 NNTs shows chirality dependent behavior. On the contrary, both g-CNNTs and C 2 NNTs show strong dependent bandgap behaviors on tube's diameter, rather than chirality. This study's findings on regulating the band gap of C x N y NTs could inspire new approaches for generating C x N y -based semiconductor materials and wide band gap semiconductor materials. [Display omitted] [ABSTRACT FROM AUTHOR]