Extraordinary Room-Temperature Photoluminescence in Triangular WS2 Monolayers


Gutıerrez H. R., Perea-Lopez N., Elıas A. L., Berkdemir A., Wang B., Lv R., ...More

NANO LETTERS, vol.13, no.8, pp.3447-3454, 2013 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 13 Issue: 8
  • Publication Date: 2013
  • Doi Number: 10.1021/nl3026357
  • Journal Name: NANO LETTERS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.3447-3454
  • Keywords: Metal dichalcogenides, tungsten disulfide, 2D materials, photoluminescence, Raman, INORGANIC FULLERENE-LIKE, MOS2 ATOMIC LAYERS, LARGE-AREA, OPTICAL-ABSORPTION, CRYSTAL-STRUCTURES, 1ST PRINCIPLES, MS2 M, GROWTH, PHASE, FILMS
  • Kayseri University Affiliated: No

Abstract

Individual monolayers of metal dichalcogenides are atomically thin two-dimensional crystals with attractive physical properties different from those of their bulk counterparts. Here we describe the direct synthesis of WS2 monolayers with triangular morphologies and strong room-temperature photoluminescence (PL). The Raman response as well as the luminescence as a function of the number of S-W-S layers is also reported. The PL weakens with increasing number of layers due to a transition from direct band gap in a monolayer to indirect gap in multilayers. The edges of WS2 monolayers exhibit PL signals with extraordinary intensity, around 25 times stronger than that at the platelet's center. The structure and chemical composition of the platelet edges appear to be critical for PL enhancement.