The edges of two-dimensional(2D)materials can exhibit special structure and thus distinctive properties differing from the interior,such as the modified photoluminescence emission,the improved electrocatalytic activit...The edges of two-dimensional(2D)materials can exhibit special structure and thus distinctive properties differing from the interior,such as the modified photoluminescence emission,the improved electrocatalytic activity,and the enhanced nonlinear optical response.In this work,we report the observation of abrupt enhancement of Raman scattered light at edges of layered MoS_(2),which is closely related to the polarization of the incident light.More importantly,the intensity of out-of-plane A1g mode is enhanced much more obviously than the in-plane E_(2g)^(1)mode.The unique optical effect at edges is also reflected on the alteration of Raman selection rule.The forbidden Raman modes are observed at edge region,and the polarization of Raman scattered light can be modulated by the edge structure,which differs obviously from that of the interior.We attribute these particular performances to the modulation of the intensity and distribution of the electric field for the incident and Raman scattered light at the edge.This work provides a systematic research on the intensity and polarization modulation of the Raman scattering at edges,which would be helpful for understanding the distinctive optical properties of the edge structure.展开更多
基金supported by the Ministry of Science and Technology of China(Nos.2018YFA0703502 and 2016YFA0200104)the National Natural Science Foundation of China(Nos.51720105003,21790052,52021006,and 21974004)+1 种基金the Strategic Priority Research Program of CAS(No.XDB36030100)the Beijing National Laboratory for Molecular Sciences(No.BNLMSCXTD-202001).
文摘The edges of two-dimensional(2D)materials can exhibit special structure and thus distinctive properties differing from the interior,such as the modified photoluminescence emission,the improved electrocatalytic activity,and the enhanced nonlinear optical response.In this work,we report the observation of abrupt enhancement of Raman scattered light at edges of layered MoS_(2),which is closely related to the polarization of the incident light.More importantly,the intensity of out-of-plane A1g mode is enhanced much more obviously than the in-plane E_(2g)^(1)mode.The unique optical effect at edges is also reflected on the alteration of Raman selection rule.The forbidden Raman modes are observed at edge region,and the polarization of Raman scattered light can be modulated by the edge structure,which differs obviously from that of the interior.We attribute these particular performances to the modulation of the intensity and distribution of the electric field for the incident and Raman scattered light at the edge.This work provides a systematic research on the intensity and polarization modulation of the Raman scattering at edges,which would be helpful for understanding the distinctive optical properties of the edge structure.
