Enhanced Photoluminescence of Multiple Two-Dimensional van der Waals Heterostructures Fabricated by Layer-by-Layer Oxidation of MoS2

Sojung Kang, Yoon Seok Kim, Jae Hwan Jeong, Junyoung Kwon, Jong Hun Kim, Yeonjoon Jung, Jong Chan Kim, Bumho Kim, Sang Hyun Bae, Pinshane Y. Huang, James C. Hone, Hu Young Jeong, Jin Woo Park, Chul Ho Lee, Gwan Hyoung Lee

Research output: Contribution to journalArticlepeer-review

2 Citations (Scopus)

Abstract

Monolayer transition metal dichalcogenides (TMDs) are promising for optoelectronics because of their high optical quantum yield and strong light-matter interaction. In particular, the van der Waals (vdW) heterostructures consisting of monolayer TMDs sandwiched by large gap hexagonal boron nitride have shown great potential for novel optoelectronic devices. However, a complicated stacking process limits scalability and practical applications. Furthermore, even though lots of efforts, such as fabrication of vdW heterointerfaces, modification of the surface, and structural phase transition, have been devoted to preserve or modulate the properties of TMDs, high environmental sensitivity and damage-prone characteristics of TMDs make it difficult to achieve a controllable technique for surface/interface engineering. Here, we demonstrate a novel way to fabricate multiple two-dimensional (2D) vdW heterostructures consisting of alternately stacked MoS2 and MoOx with enhanced photoluminescence (PL). We directly oxidized multilayer MoS2 to a MoOx/1 L-MoS2 heterostructure with atomic layer precision through a customized oxygen plasma system. The monolayer MoS2 covered by MoOx showed an enhanced PL intensity 3.2 and 6.5 times higher in average than the as-exfoliated 1 L- and 2 L-MoS2 because of preserved crystallinity and compensated dedoping by MoOx. By using layer-by-layer oxidation and transfer processes, we fabricated the heterostructures of MoOx/MoS2/MoOx/MoS2, where the MoS2 monolayers are separated by MoOx. The heterostructures showed the multiplied PL intensity as the number of embedded MoS2 layers increases because of suppression of the nonradiative trion formation and interlayer decoupling between stacked MoS2 layers. Our work shows a novel way toward the fabrication of 2D material-based multiple vdW heterostructures and our layer-by-layer oxidation process is beneficial for the fabrication of high performance 2D optoelectronic devices.

Original languageEnglish
Pages (from-to)1245-1252
Number of pages8
JournalACS Applied Materials and Interfaces
Volume13
Issue number1
DOIs
Publication statusPublished - 2021 Jan 13

Keywords

  • layer-by-layer oxidation
  • molybdenum disulfide
  • molybdenum oxide
  • multiple 2D van der Waals heterostructures
  • oxygen plasma

ASJC Scopus subject areas

  • Materials Science(all)

Fingerprint Dive into the research topics of 'Enhanced Photoluminescence of Multiple Two-Dimensional van der Waals Heterostructures Fabricated by Layer-by-Layer Oxidation of MoS<sub>2</sub>'. Together they form a unique fingerprint.

Cite this