论文标题
功能性硫醇分子在互连MOS $ _2 $纳米结构的增强电子传输中的作用
The role of functional thiolated molecules on the enhanced electronic transport of interconnected MoS$_2$ nanostructures
论文作者
论文摘要
分子接头已成为通过缺陷功能化改善溶液处理分层材料的电子传输特性的有效策略。但是，关于功能化有益作用背后的微观机制的详细讨论仍然缺失。在这里，通过基于密度功能理论的第一原理计算，我们研究了对互连MOS $ _2 $模型片段系统对电子性能的影响，与不同的硫醇分子接头功能化，即硫酚，1,4-苯并二硫酚，1,2-乙二醇，1,2-乙基硫醇，和1,1,3-丙二硫醇。苯和乙二醇桥接相邻扶手椅MOS $ _2 $纳米片的键合导致电子状态在费米水平上方或处于费米水平上，从而形成了一个分子通道，用于片段之间的电子传输。此外，分子接头减少了相邻薄片之间热活化跳跃的潜在障碍，从而改善了实验中验证的电导率。对这种机制的理解有助于将未来的解决方案处理的分层材料用于2D电子设备。
Molecular linkers have emerged as an effective strategy to improve electronic transport properties on solution-processed layered materials via defect functionalization. However, a detailed discussion on the microscopic mechanisms behind the beneficial effects of functionalization is still missing. Here, by first-principles calculations based on density functional theory, we investigate the effects on the electronic properties of interconnected MoS$_2$ model flakes systems upon functionalization with different thiol molecule linkers, namely thiophenol, 1,4-benzenedithiol, 1,2-ethanedithiol, and 1,3-propanedithiol. The bonding of benzene- and ethanedithiol bridging adjacent armchair MoS$_2$ nanoflakes leads to electronic states just above or at the Fermi level, thus forming a molecular channel for electronic transport between flakes. In addition, the molecular linker reduces the potential barrier for thermally activated hopping between neighboring flakes, improving the conductivity as verified in experiments. The comprehension of such mechanisms helps in future developments of solution-processed layered materials for use on 2D electronic devices.
