title: High anisotropy of fully hydrogenated borophene.
abstract: We have studied the mechanical properties and phonon dispersions of fully hydrogenated borophene (borophane) under strains by first principles calculations. Uniaxial tensile strains along the a- and b-direction, respectively, and biaxial tensile strain have been considered. Our results show that the mechanical properties and phonon stability of borophane are both highly anisotropic. The ultimate tensile strain along the a-direction is only 0.12, but it can be as large as 0.30 along the b-direction. Compared to borophene and other 2D materials (graphene, graphane, silicene, silicane, h-BN, phosphorene and MoS2), borophane presents the most remarkable anisotropy in in-plane ultimate strain, which is very important for strain engineering. Furthermore, the phonon dispersions under the three applied strains indicate that borophane can withstand up to 5% and 15% uniaxial tensile strain along the a- and b-direction, respectively, and 9% biaxial tensile strain, indicating that mechanical failure in borophane is likely to originate from phonon instability.
authors.affiliation: Department of Physics, and Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices, Xiamen University, Xiamen 361005, China. jczheng@xmu.edu.cn.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Physics, and Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices, Xiamen University, Xiamen 361005, China. jczheng@xmu.edu.cn.
authors.forename: Tie-Yu
authors.initials: TY
authors.lastname: Lü
authors.affiliation: Department of Physics, and Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices, Xiamen University, Xiamen 361005, China. jczheng@xmu.edu.cn and Xiamen University Malaysia, 439000 Sepang, Selangor, Malaysia.
authors.forename: Hui-Qiong
authors.initials: HQ
authors.lastname: Wang
authors.affiliation: Department of Physics, National University of Singapore, Singapore 117542, Singapore.
authors.forename: Yuan Ping
authors.initials: YP
authors.lastname: Feng
authors.affiliation: Department of Physics, and Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices, Xiamen University, Xiamen 361005, China. jczheng@xmu.edu.cn and Xiamen University Malaysia, 439000 Sepang, Selangor, Malaysia and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, Xiamen University, Xiamen 361005, China.
authors.forename: Jin-Cheng
authors.initials: JC
authors.lastname: Zheng