Abstract

Owing to their unique physical properties, monolayer transition metal dichalcogenides (TMDCs) have been widely used in applications of light-emitting diodes (LEDs). However, monolayers of TMDCs undergo dramatic aging effects, including intense degradation in optical behavior, extensive cracking, and severe quenching of the direct gap photoluminescence (PL), seriously limiting the device performance. In this work, we show that monolayer WS2 stored for three months even in the glovebox exhibits obvious degenerative PL with changed peak position that can be attributed to the presence of a large number of trions induced by the aging effect. PC61BM surface processing was used to modify the surface of the aged monolayer WS2. As expected, higher uniformity in the PL spectrum was obtained. Besides, the PL peak wavelength was modified to be the same as that of the nonaged one and did not change even at higher excitation power. This strategy is shown to successfully suppress the formation of the trion by transferring the excess electrons from WS2 to PC61BM. The results demonstrate the feasibility of applying PC61BM surface modification to improve the performance of the LED based on monolayer WS2.

© 2017 Optical Society of America

Full Article  |  PDF Article
OSA Recommended Articles
Visualized charge transfer processes in monolayer composition-graded WS2xSe2(1−x) lateral heterojunctions via ultrafast microscopy mapping

Hao Hao, Zhongjie Xu, Tian Jiang, Ke Wei, Han Li, Xin Zheng, Ke Yin, Jie You, Chao Shen, and Xiang-ai Cheng
Opt. Express 26(12) 15867-15886 (2018)

Enhanced local photoluminescence of a multilayer MoS2 nanodot stacked on monolayer MoS2 flakes

Fei Chen, Lei Wang, Ting Wang, and Xiaohong Ji
Opt. Mater. Express 7(4) 1365-1373 (2017)

Nanophotonics with 2D transition metal dichalcogenides [Invited]

Alex Krasnok, Sergey Lepeshov, and Andrea Alú
Opt. Express 26(12) 15972-15994 (2018)

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Figures (4)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Metrics

You do not have subscription access to this journal. Article level metrics are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription