Moon Sooyeon, Yang Jiwoo, Kwon Deok Hwang, Cho Daeheum, Kim Jae-Keun, Shim Jae Won, Kim Heesuk, Lee Takhee, Jang Hyejin, Cho Kyungjune, Chung Seungjun
Department of Material Science and Engineering, Seoul National University, Seoul 08826, Republic of Korea.
School of Electrical and Engineering, Korea University, Seoul 02841, Republic of Korea.
Nano Lett. 2025 Jun 25;25(25):9994-10002. doi: 10.1021/acs.nanolett.5c01649. Epub 2025 Jun 12.
Ultrathin two-dimensional (2D) transition metal dichalcogenides (TMDs) exhibit unique band structures, allowing promising thermoelectric properties. Achieving a high power factor () for thermoelectric generators (TEGs) requires optimizing both the Seebeck coefficient () and electrical conductivity (). Conventional surface charge-transfer doping can be a solution to enhance by introducing additional electrons. However, residual organic dopants act as charged impurities, degrading charge transport and lowering due to the intensified trade-off between carrier concentration and . We propose a charged-impurity-free diffusion doping method for CVD-grown molybdenum disulfide (MoS) to enhance . By depositing organic dopants on the contact region and enabling electron diffusion into the channel via carrier concentration gradients, is improved while maintaining high . This approach achieves a record-high of 1698 μW/mK for CVD-grown TMDs. Our strategy offers a promising pathway to enhance thermoelectric performance, not limited by the exacerbated trade-off relationship observed in conventional doping methods.
超薄二维（2D）过渡金属二硫属化物（TMDs）展现出独特的能带结构，具备有望实现的热电性能。要实现热电发电机（TEGs）的高功率因数（），需要同时优化塞贝克系数（）和电导率（）。传统的表面电荷转移掺杂可以作为通过引入额外电子来提高的一种解决方案。然而，残留的有机掺杂剂会作为带电杂质，由于载流子浓度和之间加剧的权衡，会降低电荷传输并降低。我们提出了一种用于化学气相沉积（CVD）生长的二硫化钼（MoS）的无带电杂质扩散掺杂方法来提高。通过在接触区域沉积有机掺杂剂并通过载流子浓度梯度使电子扩散到沟道中，在保持高的同时提高了。这种方法为CVD生长的TMDs实现了创纪录的1698 μW/mK的高。我们的策略为提高热电性能提供了一条有前景的途径，不受传统掺杂方法中观察到的加剧的权衡关系的限制。
