Acta Phys. -Chim. Sin. ›› 2017, Vol. 33 ›› Issue (8): 1514-1519.doi: 10.3866/PKU.WHXB201705123

• COMMUNICATION • Previous Articles     Next Articles

Preferential Substitution of Selenium along the Grain Boundaries in Monolayer MoS2(1-x)Se2x Alloy

Dan-Hui LÜ,Dan-Cheng ZHU,Chuan-Hong JIN*()   

  • Received:2017-03-27 Published:2017-06-14
  • Contact: Chuan-Hong JIN
  • Supported by:
    the National Natural Science Foundation of China(51472215);the National Natural Science Foundation of China(51222202)


We report a microscopic study on the process for the substitution of selenium into monolayer molybdenum disulfide via a joint CVD-STEM characterization. Results from quantitative and statistic STEM reveal that the concentration of Se atoms in grain boundaries is much higher than that in intra-domains of monolayer MoS2(1-x)Se2x alloy. In-depth analysis finds that Se atoms are enriched in the distorted regions due to presence of dislocation cores on the grain boundary, which can be further understood by considering the difference of chemical reactivity for doping reaction in different types of grain boundaries with different symmetry and different misorientation angles. Our results pave the way towards the controlled growth of alloyed two-dimensional transition metal dichalcogenide materials with a high precision, and their further applications.

Key words: MoS2(1-x)Se2x alloy, Grain boundary enrichment, Atomic-resolution scanning transmission electron microscopy