Compact Super Electron-Donor to Monolayer MoS 2
Compact Super Electron-Donor to Monolayer MoS 2
复制标题
单层 MoS 2 的紧凑型超级电子给体
DOI：
10.1021/acs.nanolett.2c01167
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发表时间：
2022
期刊：
影响因子：
10.8
通讯作者：
Quek, Su Ying
中科院分区：
文献类型：
--
作者：
Reed-Lingenfelter, Serrae N.;Chen, Yifeng;Yarali, Milad;Charboneau, David J.;Curley, Julia B.;Hynek, David J.;Wang, Mengjing;Williams, Natalie L.;Hazari, Nilay;Quek, Su Ying
利用有机电子给体（OEDs）对二维材料进行表面功能化是调控材料电子性质的有力工具。本文报道了一种新的分子掺杂剂Me-OED，它对MoS 2进行了破纪录的分子掺杂，在最佳功能化条件下实现了1.10 ± 0.37 × 1014 cm-2的载流子密度，远高于苄基紫精和基于4，4 ′-联吡啶的OED。这种令人印象深刻的掺杂能力归因于Me-OED的紧凑尺寸，这导致MoS 2上的高表面覆盖率。为了证实，我们研究tBu-OED，它具有与Me-OED相同的还原潜力，但显着更大。使用场效应晶体管测量和光谱表征，我们估计的掺杂功率的Me-和tBu-OED是0.22-0.44和0.11电子每分子，分别与计算结果吻合得很好。我们的研究结果表明，小尺寸的Me-OED对于最大化表面覆盖率和与MoS 2的分子相互作用至关重要，使我们能够实现前所未有的MoS 2掺杂。
The surface functionalization of two-dimensional (2D) materials with organic electron donors (OEDs) is a powerful tool to modulate the electronic properties of the material. Here we report a novel molecular dopant, Me-OED, that demonstrates record-breaking molecular doping to MoS2, achieving a carrier density of 1.10 ± 0.37 × 1014cm–2at optimal functionalization conditions; the achieved carrier density is much higher than those by other OEDs such as benzyl viologen and an OED based on 4,4′-bipyridine. This impressive doping power is attributed to the compact size of Me-OED, which leads to high surface coverage on MoS2. To confirm, we studytBu-OED, which has an identical reduction potential to Me-OED but is significantly larger. Using field-effect transistor measurements and spectroscopic characterization, we estimate the doping powers of Me- andtBu-OED are 0.22–0.44 and 0.11 electrons per molecule, respectively, in good agreement with calculations. Our results demonstrate that the small size of Me-OED is critical to maximizing the surface coverage and molecular interactions with MoS2, enabling us to achieve unprecedented doping of MoS2.