Ullah Saif, Denis Pablo A, Sato Fernando
Departamento de Física, Instituto de Ciências Exatas, Campus Universitário, Universidade Federal de Juiz de Fora Juiz de Fora MG 36036-900 Brazil +55 589229241906 +55 59899714280.
Computational Nanotechnology, DETEMA, Facultad de Química, UDELAR CC 1157 11800 Montevideo Uruguay
RSC Adv. 2019 Nov 18;9(64):37526-37536. doi: 10.1039/c9ra07338h. eCollection 2019 Nov 13.
By means of first-principles calculations, we study the structural, electronic and mechanical properties of the newly synthesized boron-oxygen holey framework ( 2018, , 3971). It has a planar structure formed by BO hexagons, which are joined strong covalent boron-boron bonds. The six BO units are connected with six-fold symmetry exhibiting a large hole with a surface area of 23 Å, which is ideal for the adsorption of alkalis. For neutral alkalis, we found that the adsorption energy of potassium is 14 and 12 kcal mol larger than those determined for sodium and lithium, respectively. In contrast, for alkali cations, there is a clear preference for lithium over sodium and potassium. With regard to its electronic properties, it is an insulator with an electronic band gap of 5.3 eV, at the HSE level of theory. We further investigate the effect of strain on the band gap and find it a less efficient technique to tune the electronic properties. The wide optical gap of BO can be utilized in ultraviolet (UV) applications, such as UV photodetectors, Additionally, the 2D elastic modulus of BO (53.9 N m) is larger than that of BeN, silicene, and germanene. Besides, we also report bilayer and graphite-like bulk BO and furthermore, find that the optoelectronic properties of the bilayer can be tuned with an external electric field. The great tunability of optical properties from UV to the visible range offers a vast range of applications in optoelectronics.
通过第一性原理计算，我们研究了新合成的硼 - 氧多孔框架的结构、电子和力学性能（2018年，，3971）。它具有由BO六边形形成的平面结构，这些六边形通过强共价硼 - 硼键连接。六个BO单元以六重对称性连接，呈现出一个表面积为23 Å的大孔，这对于碱金属的吸附非常理想。对于中性碱金属，我们发现钾的吸附能分别比钠和锂的吸附能大14和12 kcal/mol。相比之下，对于碱金属阳离子，锂明显优于钠和钾。关于其电子性质，在HSE理论水平下，它是一种带隙为5.3 eV的绝缘体。我们进一步研究了应变对带隙的影响，发现这是一种调节电子性质效率较低的技术。BO的宽光学带隙可用于紫外线（UV）应用，如UV光电探测器。此外，BO的二维弹性模量（53.9 N/m）大于BeN、硅烯和锗烯的弹性模量。此外，我们还报道了双层和类石墨体BO，并且发现双层的光电性质可以通过外部电场进行调节。从紫外线到可见光范围的光学性质的巨大可调性在光电子学中提供了广泛的应用。
