Direct Covalent Chemical Functionalization of Unmodified Two-Dimensional Molybdenum Disulfide
Direct Covalent Chemical Functionalization of Unmodified Two-Dimensional Molybdenum Disulfide
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DOI：
10.1021/acs.chemmater.8b00173
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发表时间：
2018-03-27
影响因子：
8.6
通讯作者：
Wang, Qing Hua
中科院分区：
文献类型：
--
作者：
Chu, Ximo S.;Yousaf, Ahmed;Wang, Qing Hua
二维半导体过渡金属二硫属化物（TMDC）如二硫化钼（MoS 2）由于其独特的电子、化学和光学性质而产生显著的兴奋。共价化学官能化代表了用于调节TMDC的性质以用于许多应用的关键工具。然而，迄今为止，半导体TMDC的化学惰性阻碍了这些材料的稳健化学官能化。先前的报道要求苛刻的化学处理或在共价连接之前将TMDC转化成金属相。在这里，我们证明了直接共价官能化的未改性的半导体MoS 2使用芳基重氮盐，而无需任何预处理的基面。我们的方法保留了MoS 2的半导体性质，导致共价C-S键，适用于来自一系列不同合成方法的MoS 2，并使一系列不同的官能团能够直接连接到MoS 2表面。使用密度泛函理论计算，包括货车德瓦尔斯相互作用和原子尺度的扫描探针显微镜的研究，我们证明了一种新的反应机制，其中合作的相互作用，使功能化传播沿着的二硫化钼基面。进一步利用采用不同芳基重氮盐家族的这种共价化学的灵活性来将活性蛋白质束缚到MoS 2，这表明了未来的生物应用，并证明了其作为用于增强半导体TMDC的效用的通用且强大的化学平台的用途。
Two-dimensional semiconducting transition metal dichalcogenides (TMDCs) like molybdenum disulfide (MoS2) are generating significant excitement due to their unique electronic, chemical, and optical properties. Covalent chemical functionalization represents a critical tool for tuning the properties of TMDCs for use in many applications. However, the chemical inertness of semiconducting TMDCs has thus far hindered the robust chemical functionalization of these materials. Previous reports have required harsh chemical treatments or converting TMDCs into metallic phases prior to covalent attachment. Here, we demonstrate the direct covalent functionalization of the basal planes of unmodified semiconducting MoS2 using aryl diazonium salts without any pretreatments. Our approach preserves the semiconducting properties of MoS2, results in covalent C-S bonds, is applicable to MoS2 derived from a range of different synthesis methods, and enables a range of different functional groups to be tethered directly to the MoS2 surface. Using density functional theory calculations including van der Waals interactions and atomic-scale scanning probe microscopy studies, we demonstrate a novel reaction mechanism in which cooperative interactions enable the functionalization to propagate along the MoS2 basal plane. The flexibility of this covalent chemistry employing the diverse aryl diazonium salt family is further exploited to tether active proteins to MoS2, suggesting future biological applications and demonstrating its use as a versatile and powerful chemical platform for enhancing the utility of semiconducting TMDCs.