Tuning electronic properties in the C3N/C3B lateral heterostructures

The successful fabrication of the lateral heterostructures (LHSs) open a promising avenue for the band structure engineering. Here, we design novel (C3N)2(C3B)2 LHSs integrating monolayer C3N and C3B along different directions and predict their electronic properties based on the density functional theory. It is found that (C3N)2(C3B)2 LHSs stitched semi-infinite monolayers along both armchair and zigzag directions exhibit excellent stability. Remarkably, the band structures of both armchair-(C3N)2(C3B)2 and zigzag-(C3N)2(C3B)2 LHSs undergo an indirect to direct transition, by contrast, both pristine C3N and C3B monolayers are indirect band gap semiconductors. The type-II band alignment in the zigzag-(C3N)2(C3B)2 has been revealed. In addition, the tensile strain can effectively modulate the band structures. Especially, the band of zigzag-(C3N)2(C3B)2 is reversed under the tensile strain along the zigzag direction.