Bulk structure of Si2BN predicted by computational approaches

• Published in: Diamond and related materials 2022-12, Vol.130, p.109530, Article 109530
• Main Authors: Wang, Jiawen, Chen, Shangqian, Yang, Yingke, Yu, Yi, Dong, Huilong, Li, Youyong
• Format: Article
• Language: English
• Subjects: High-temperature resistant material; Particle swarm optimization; Si2BN; Structural prediction
• ISSN: 0925-9635; 1879-0062
• DOI: 10.1016/j.diamond.2022.109530

Recently, the theoretically predicted single-layer silicon boron nitride (Si2BN) has gained wide scientific interests. However, there still lack of studies on its bulk counterpart. In this work, we computationally predicted the bulk structures of Si2BN by combining particle swarm optimization (PSO) algorithm with first-principles calculations. For the PSO screened structures, we confirmed that the α-phase (α-Si2BN) is the most probable structure of bulk Si2BN, by evaluating from crystal symmetry, average atomic formation enthalpy and phonon dispersion spectrum. The electronic band structure of α-Si2BN indicates that it's semiconducting with an ultra-narrow indirect band gap (0.02 eV). Moreover, investigations on mechanical and thermal properties reveal that the α-Si2BN exhibits considerable hardness, ultra-high Debye temperature (1001K) and ultra-high melting point (2600 K), which holds great potential as high-temperature resistant material. [Display omitted] •We predicted new bulk Si2BN by PSO algorithm and first-principles calculations.•α-phase Si2BN is semiconducting with an ultra-narrow indirect bandgap.•α-phase Si2BN is a candidate as high-temperature resistant material.