Doping lies at the heart of modern semiconductor technologies. Therefore, for two-dimensional (2D) semiconducting transition metal dichalcogenides (TMDs), the significance of controlled doping is no exception. Recent studies have indicated that, by substitutionally doping 2D TMDs with a judicious selection of dopants, their electrical, optical, magnetic, and catalytic properties can be effectively tuned, endowing them with great potential for various practical applications. Herein, and inspired by the sol-gel process, we report a liquid-phase precursor-assisted approach for in situ substitutional doping of monolayered TMDs and their in-plane heterostructures with tunable doping concentration. This highly reproducible route is based on the high-temperature chalcogenation of spin-coated aqueous solutions containing host and dopant precursors. The precursors are mixed homogeneously at the atomic level in the liquid phase prior to the synthesis process, thus allowing for an improved doping uniformity and controllability. We further demonstrate the incorporation of various transition metal atoms, such as iron (Fe), rhenium (Re), and vanadium (V), into the lattice of TMD monolayers to form Fe-doped WS2, Re-doped MoS2, and more complex material systems such as V-doped in-plane WxMo1-xS2-MoxW1-xS2 heterostructures, among others. We envisage that our developed approach is universal and could be extended to incorporate a variety of other elements into 2D TMDs and create in-plane heterointerfaces in a single step, which may enable applications such as electronics and spintronics at the 2D limit.

中文翻译：

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液相前驱体辅助合成方法制备过渡金属二硫属元素化物的通用原位取代掺杂。

掺杂是现代半导体技术的核心。因此，对于二维（2D）半导体过渡金属二卤化金属（TMD），受控掺杂的重要性也不例外。最近的研究表明，通过明智地选择掺杂剂对2D TMD进行掺杂掺杂，可以有效地调节其电，光，磁和催化性能，使其在各种实际应用中具有巨大的潜力。在这里，受溶胶-凝胶工艺的启发，我们报告了液相前驱物辅助方法对单层TMD及其可调整掺杂浓度的面内异质结构进行原位取代掺杂。这种高度可重复的途径是基于含有主体和掺杂剂前体的旋涂水溶液的高温硫磺化。在合成过程之前，将前体在液相中在原子水平上均匀混合，从而改善掺杂均匀性和可控性。我们进一步证明了将各种过渡金属原子（例如铁（Fe），rh（Re）和钒（V））掺入TMD单层晶格中以形成掺铁的WS2，掺重的MoS2和更复杂的材料系统，例如V掺杂平面内WxMo1-xS2-MoxW1-xS2异质结构。我们设想，我们开发的方法是通用的，可以扩展为将各种其他元素合并到2D TMD中，并在一个步骤中创建平面内异质接口，这可能使2D极限的电子和自旋电子学等应用成为可能。