Zhou Yong, Cheng Beitong, Huang Shuai, Huang Xingyong, Jiang Ruomei, Wang Xule, Zhang Wei, Jia Baonan, Lu Pengfei, Song Hai-Zhi
Quantum Research Center, Southwest Institute of Technical Physics, Chengdu 610041, China.
School of Electronic Engineering, Chengdu Technological University, Chengdu 611730, China.
Nanomaterials (Basel). 2023 Oct 20;13(20):2798. doi: 10.3390/nano13202798.
Two-dimensional (2D) bismuth oxyhalides (BiOX) have attracted much attention as potential optoelectronic materials. To explore their application diversity, we herewith systematically investigate the tunable properties of 2D BiOX using first-principles calculations. Their electronic and optical properties can be modulated by changing the number of monolayers, applying strain, and/or varying the halogen composition. The band gap shrinks monotonically and approaches the bulk value, the optical absorption coefficient increases, and the absorption spectrum redshifts as the layer number of 2D BiOX increases. The carrier transport property can be improved by applying tensile strain, and the ability of photocatalytic hydrogen evolution can be obtained by applying compressive strain. General strain engineering will be effective in linearly tuning the band gap of BiOX in a wide strain range. Strain, together with halogen composition variation, can tune the optical absorption spectrum to be on demand in the range from visible to ultraviolet. This suggests that 2D BiOX materials can potentially serve as tunable novel photodetectors, can be used to improve clean energy techniques, and have potential in the field of flexible optoelectronics.
二维（2D）卤氧化铋（BiOX）作为潜在的光电子材料备受关注。为了探索其应用多样性，我们在此使用第一性原理计算系统地研究二维BiOX的可调谐特性。它们的电子和光学性质可以通过改变单层数量、施加应变和/或改变卤素组成来调节。随着二维BiOX层数的增加，带隙单调缩小并接近体相值，光吸收系数增加，吸收光谱发生红移。通过施加拉伸应变可以改善载流子传输性能，通过施加压缩应变可以获得光催化析氢能力。一般的应变工程将有效地在很宽的应变范围内线性调节BiOX的带隙。应变与卤素组成变化一起，可以将光吸收光谱调节到从可见光到紫外光的所需范围。这表明二维BiOX材料有潜力作为可调谐的新型光电探测器，可用于改进清洁能源技术，并在柔性光电子领域具有潜力。
