Ha Chu Viet, Ha L T, Hue Do Thi, Nguyen Duy Khanh, Anh Dang Tuan, Guerrero-Sanchez J, Hoat D M
Faculty of Physics, TNU-University of Education Thai Nguyen 250000 Vietnam.
Institute of Science and Technology, TNU-University of Science Thai Nguyen 250000 Vietnam.
RSC Adv. 2023 May 16;13(22):14879-14886. doi: 10.1039/d3ra01372c. eCollection 2023 May 15.
Chemical adsorption of non-metal atoms may lead to the emergence of novel features in two-dimensional (2D) materials. In this work, the electronic and magnetic properties of graphene-like XC (X = Si and Ge) monolayers with adsorbed H, O, and F atoms are investigated using spin-polarized first-principles calculations. Deeply negative adsorption energies suggest strong chemical adsorption on XC monolayers. Despite the non-magnetic nature of both host monolayer and adatom, SiC is significantly magnetized by H adsorption inducing the magnetic semiconductor nature. Similar features are observed in GeC monolayers upon adsorbing H and F atoms. In all cases, an integer total magnetic moment of 1 is obtained, originating mainly from adatoms and their neighbor X and C atoms. In contrast, O adsorption preserves the non-magnetic nature of SiC and GeC monolayers. However, the electronic band gaps exhibit significant reduction of the order of 26% and 18.84%, respectively. These reductions are consequences of the middle-gap energy branch generated by the unoccupied O-p state. The results introduce an efficient approach to develop d 2D magnetic materials to be applied in spintronic devices, as well as to widen the working region of XC monolayers in optoelectronic applications.
非金属原子的化学吸附可能会导致二维（2D）材料出现新特性。在这项工作中，使用自旋极化第一性原理计算研究了吸附有H、O和F原子的类石墨烯XC（X = Si和Ge）单层的电子和磁性特性。深度负吸附能表明在XC单层上有强烈的化学吸附。尽管主体单层和吸附原子均无磁性，但SiC通过H吸附被显著磁化，从而呈现出磁性半导体特性。在吸附H和F原子的GeC单层中也观察到类似特征。在所有情况下，总磁矩均为整数1，主要源于吸附原子及其相邻的X和C原子。相比之下，O吸附保持了SiC和GeC单层的非磁性特性。然而，电子带隙分别显著减小了26%和18.84%。这些减小是由未占据的O-p态产生的中间能隙能量分支导致的。这些结果为开发用于自旋电子器件的二维磁性材料以及拓宽XC单层在光电子应用中的工作区域引入了一种有效方法。
