Department of Chemical Engineering, Kansas State University , 1005 Durland Hall, Manhattan, Kansas, 66502, United States.
Nano Lett. 2013 Sep 11;13(9):4434-41. doi: 10.1021/nl402278y. Epub 2013 Aug 13.
Ultrathin (0.3-3 nm) metal dichalcogenides exhibit confinement of carriers, evolution of band-structure and photophysical properties with thickness, high on/off rectification (in MoS2, WS2, and so forth) and high thermal absorption. Here, we leverage the stable sulfur/nobel-metal binding to incorporate highly capacitive gold nanoparticles (Au NPs) onto MoS2 to raise the effective gate-voltage by an order of magnitude. Functionalization is achieved via both diffusion limited aggregation and instantaneous reaction arresting (using microwaves) with selective deposition on crystallographic edges (with 60° displacement). The electrical, thermal, and Raman studies show a highly capacitive interaction between Au NP and MoS2 flakes (CAu-MoS2 = 2.17 μF/cm(2)), a low Schottky barrier (14.52 meV), a reduced carrier-transport thermal-barrier (253 to 44.18 meV after Au NP functionalization), and increased thermal conductivity (from 15 to 23 W/mK post NP deposition). The process could be employed to attach electrodes to heterostructures of graphene and MoS2, where a gold film could be grown to act as an electron-tunneling gate-electrode connected to MoS2.
超薄(0.3-3nm)金属二卤化物表现出对载流子的限制、带结构和光物理性质随厚度的演化、高开关比(在 MoS2、WS2 等中)和高热吸收。在这里,我们利用稳定的硫/贵金属结合,将高电容的金纳米粒子(Au NPs)掺入 MoS2 中,将有效栅极电压提高一个数量级。功能化是通过扩散限制聚集和瞬时反应停止(使用微波)实现的,在晶面边缘(60°位移)选择性沉积。电学、热学和拉曼研究表明,Au NP 和 MoS2 片之间存在高电容相互作用(CAu-MoS2=2.17 μF/cm2),肖特基势垒较低(14.52meV),载流子输运热势垒降低(Au NP 功能化后从 253 至 44.18meV),热导率增加(从 15 至 23W/mK 后 NP 沉积)。该过程可用于将电极附着到石墨烯和 MoS2 的异质结构上,在那里可以生长金膜作为连接到 MoS2 的电子隧道栅电极。