Congratulation Hye Yun for ACS NANO paper acceptance!
Great effort to observe point defects in TMDs.
Title: Visualizing Point Defects in Transition Metal Dichalcogenides using Optical Microscopy
Authors: Hye Yun Jeong, Si Young Lee, Thuc Hue Ly, Gang Hee Han, Hyun Kim, Honggi Nam, Zhao Jiong, Bong Gyu Shin, Seok Jun Yun, Jaesu Kim, Un Jeong Kim§, Sungwoo Hwang§ & Young Hee Lee
Abstract: While transmission electron microscopy and scanning tunneling microscopy reveal atomic structures of point defect and grain boundary in monolayer transition metal dichalcogenides (TMDs), information on point defect distribution in macroscale is still not available. Herein, we visualize the point defect distribution of monolayer TMDs using dark-field optical microscopy. This was realized by anchoring silver nanoparticles on defect sites of MoS2 under light illumination. The optical images clearly revealed that the point defect distribution varies with light power and exposure time. The number of silver nanoparticles increased initially and reached a plateau in response to light power or exposure time. The size of silver nanoparticles was a few hundred nanometers in the plateau region as observed using optical microscopy. The measured defect density in macroscale was ~2 × 1010 cm-2, slightly lower than the observed value (4 × 1011 cm-2) from scanning tunneling microscopy.