论文标题
对锌混合镉硒化锌（CDSE）纳米线的机械性能和故障行为的原子研究
Atomistic Investigation on the Mechanical Properties and Failure Behavior of Zinc Blende Cadmium Selenide (CdSe) Nanowire
论文作者
论文摘要
硒化镉（CDSE）纳米线的机械性能是由于其在半导体和光电工业中的应用而成为新兴问题。在本文中，我们进行了分子动力学（MD）模拟，以研究单轴拉伸变形的温度依赖性机械性能和锌 - 搅拌（ZB）CDSE纳米线的失效行为。我们利用Stillinger-Weber（SW）潜力来描述原子间相互作用。研究了温度（100 k-600 K），大小和晶体方向对CDSE纳米线的拉伸反应的影响。我们的仿真结果表明，CDSE的最终拉伸强度和Youngs模量与温度都有反比关系。从100K到600K，ZB CDSE表现出脆性型故障，因此没有发现易碎的延性过渡温度。结果还表明，大小对CDSE纳米线的机械性能具有显着影响。已经发现，随着横截面区域增加最终的拉伸应力，幼体模量也会增加。 [111]面向的ZB CDSE显示出最大的终极拉伸强度，年轻的模量和断裂韧性，而[100]方向的值最低。 [110]方向与其他方向相比显示出最大的故障菌株。最后，在100K和600K处还研究了CDSE纳米线的故障机制。我们注意到，在100K温度[100]方向的ZB CDSE沿{111}裂解平面失败，但是在600 K温度的情况下，{111}和{100}平面都被激活并导致CDSE纳米线的断裂，以较低的应变值。这项研究可以指导基于ZB CDSE的太阳能电池，光电子和半导体设备，通过对该纳米线的机械和断裂特性有全面的理解。
The mechanical properties of Cadmium Selenide (CdSe) nanowire is an emerging issue due to its application in semiconductor and optoelectronics industries. In this paper, we conducted molecular dynamics (MD) simulations to investigate the temperature-dependent mechanical properties and failure behavior of Zinc-Blende (ZB) CdSe nanowire under uniaxial tensile deformation. We employed Stillinger-Weber (SW) potential to describe the inter-atomic interactions. The effect of variation of temperatures (100 K-600 K), sizes, and crystal orientation on the tensile response of the CdSe nanowires is investigated. Our simulation results suggest that both ultimate tensile strength and Youngs modulus of CdSe have an inverse relationship with temperature. From 100K to 600K, the ZB CdSe exhibits brittle type failure thus there is no brittle to ductile transition temperature found. Results also suggest that size has a significant effect on the mechanical properties of CdSe nanowire. It has been found that as the cross-sectional area increases both ultimate tensile stress and Youngs modulus increases as well. The [111] oriented ZB CdSe shows the largest ultimate tensile strength, Youngs modulus and fracture toughness whereas the values are lowest for [100] orientation. The [110] orientation shows the largest failure strain compared to other orientations. Finally, failure mechanisms of CdSe nanowire are also investigated at 100K and 600K. We noticed that at 100K temperature [100] oriented ZB CdSe fails along {111} cleavage plane however in the case of 600 K temperature, both {111} and {100} planes are activated and cause fracture of CdSe nanowire at lower strain value. This study can guide to design ZB CdSe based solar cell, optoelectronic and semiconductor devices by presenting a comprehensive understanding of the mechanical and fracture characteristics of this nanowire.
