Electronic and effective mass modulation in 2D BCN by strain engineering

2D BCN material consisting of graphene and hexagonal boron nitride (h-BN) has received extensive attention due to its abundant electronic properties and promising applications. The actual applications of 2D BCN require that there be precise control over its electronic properties. Using density functional theory calculations, we systematically investigate the electronic structure and effective mass of 2D BCN under biaxial strain. It is demonstrated that the band gap of zigzag BCNs decreases monotonously as the tensile strain increases. Moreover, the system exhibits a similar trend, regardless of the C/h-BN ratio. In sharp contrast, the band gap of armchair BCNs depends on the C/h-BN ratio. Specifically, the band gap of C₂(BN)₄ decreases significantly, while the band gap of C₃(BN)₃ and C₄(BN)₂ initially remains almost unchanged and then increases with increasing biaxial strain in armchair BCNs. In addition, it is found that the effective masses of the electron and hole of BCNs can be effectively modulated by the biaxial strain. Our results suggest a new route to control the electronic properties of 2D BCN and may also facilitate the realization of electronic devices based on 2D BCN material.