Robust growth of two-dimensional metal dichalcogenides and their alloys by active chalcogen monomer supply.
Yonggang ZuoCan LiuLiping DingRuixi QiaoJinpeng TianChang LiuQinghe WangGuodong XueYilong YouQuanlin GuoJinhuan WangYing FuKehai LiuXu ZhouHao HongMuhong WuXiaobo LuRong YangGuangyu ZhangDapeng YuEnge WangXuedong BaiFeng DingKai-Hui LiuPublished in: Nature communications (2022)
The precise precursor supply is a precondition for controllable growth of two-dimensional (2D) transition metal dichalcogenides (TMDs). Although great efforts have been devoted to modulating the transition metal supply, few effective methods of chalcogen feeding control were developed. Here we report a strategy of using active chalcogen monomer supply to grow high-quality TMDs in a robust and controllable manner, e.g., MoS 2 monolayers perform representative photoluminescent circular helicity of ~92% and electronic mobility of ~42 cm 2 V -1 s -1 . Meanwhile, a uniform quaternary TMD alloy with three different anions, i.e., MoS 2(1-x-y) Se 2x Te 2y , was accomplished. Our mechanism study revealed that the active chalcogen monomers can bind and diffuse freely on a TMD surface, which enables the effective nucleation, reaction, vacancy healing and alloy formation during the growth. Our work offers a degree of freedom for the controllable synthesis of 2D compounds and their alloys, benefiting the development of high-end devices with desired 2D materials.