Ab Initio-Based Bond Order Potential to Investigate Low Thermal Conductivity of Stanene Nanostructures
Ab Initio-Based Bond Order Potential to Investigate Low Thermal Conductivity of Stanene Nanostructures
复制标题
DOI：
10.1021/acs.jpclett.6b01562
复制
发表时间：
2016-10-06
影响因子：
5.7
通讯作者：
Sankaranarayanan, Subramanian K. R. S.
中科院分区：
文献类型：
--
作者：
Cherukara, Mathew J.;Narayanan, Badri;Sankaranarayanan, Subramanian K. R. S.
我们引入了基于从头算导出的训练数据集的stanene键序势（BOP）。该电位被优化为精确描述独立薄片的能量学、热学和机械性能，并用于研究各种纳米结构的stanene，包括管状和带状。作为一个代表性的案例研究，我们使用势，进行分子动力学模拟来研究stanene的结构和温度相关的导热性。我们发现，由于其较低的平面内刚度（stanene：类似于25 N/m；石墨烯：类似于480 N/m）， stanene的结构具有高度波纹，远远超过其他二维材料（例如石墨烯）。与石墨烯相比，石墨烯的波纹程度也表现出更强的温度依赖性。此外，我们发现基于stanene的纳米结构由于其柔软性（即低声子群速度）和高非谐波响应，与基于石墨烯的结构相比，其导热系数显着降低。我们新开发的防喷器将促进热电和热管理应用的尺寸异质结构。以stanene为基础的勘探
We introduce a bond order potential (BOP) for stanene based on an ab initio derived training data set. The potential is optimized to accurately describe the energetics, as well as thermal and mechanical properties of a free-standing sheet, and used to study diverse nanostructures of stanene, including tubes and ribbons. As a representative case study, using the potential, we perform molecular dynamics simulations to study stanene's structure and temperature-dependent thermal conductivity. We find that the structure of stanene is highly rippled, far in excess of other 2-D materials (e.g., graphene), owing to its low in-plane stiffness (stanene: similar to 25 N/m; graphene: similar to 480 N/m). The extent of stanene's rippling also shows stronger temperature dependence compared to that in graphene. Furthermore, we find that stanene based nanostructures have significantly lower thermal conductivity compared to graphene based structures owing to their softness (i.e., low phonon group velocities) and high anharmonic response. Our newly developed BOP will facilitate dimensional heterostructures for thermoelectric and thermal management applications. the exploration of stanene based low