Chen Lanli, Cui Yuanyuan, Xiong Zhihua, Zhou Mingbin, Gao Yanfeng
School of Mathematics and Physics, Hubei Polytechnic University Huangshi 435003 China.
School of Materials Science and Engineering, Shanghai University Shanghai 200444 China
RSC Adv. 2019 Jul 15;9(38):21831-21843. doi: 10.1039/c9ra03484f. eCollection 2019 Jul 11.
Two-dimensional zinc oxide (ZnO) materials have been extensively investigated both experimentally and theoretically due to their novel properties and promising applications in optoelectronic and spintronic devices; however, how to tune the electronic property of the ZnO monolayer is still a challenge. Herein, employing the first-principles calculations, we explored the effect of chemical functionalization on the structural and electronic properties of the ZnO monolayer. The results demonstrated that the hydrogenated-, fluorinated- or Janus-functionalized ZnO monolayers were thermodynamically and mechanically stable except for the fully hydrogenated ZnO monolayer. The band gap of the ZnO monolayer could be effectively modulated by hydrogenation or fluorination, which varied from 0 to 2.948 eV, as obtained by the PBE functional, and from 0 to 5.114 eV, as obtained by the HSE06 functional. In addition, a nonmagnetic metal → nonmagnetic semiconductor transition was achieved after hydrogenation, whereas a transition from a magnetic half-metal to nonmagnetic semiconductor occurred after fluorination of the ZnO monolayer. These results demonstrate that tunability of the electronic properties of the ZnO monolayer can be realized by chemical functionalization for future nanoelectronic device applications.
二维氧化锌（ZnO）材料因其新颖的性质以及在光电器件和自旋电子器件中颇具前景的应用而在实验和理论方面都得到了广泛研究；然而，如何调控ZnO单层的电子性质仍是一项挑战。在此，我们采用第一性原理计算方法，探究了化学功能化对ZnO单层结构和电子性质的影响。结果表明，除了完全氢化的ZnO单层外，氢化、氟化或Janus功能化的ZnO单层在热力学和力学上都是稳定的。ZnO单层的带隙可通过氢化或氟化有效调制，采用PBE泛函得到的带隙变化范围为0至2.948 eV，采用HSE06泛函得到的带隙变化范围为0至5.114 eV。此外，氢化后实现了从非磁性金属到非磁性半导体的转变，而ZnO单层氟化后则发生了从磁性半金属到非磁性半导体的转变。这些结果表明，通过化学功能化可实现ZnO单层电子性质的可调控性，以用于未来的纳米电子器件应用。
