Extraordinary room-temperature photoluminescence in triangular WS 2 monolayers

Humberto R. Gutiérrez, Nestor Perea-López, Ana Laura Elías, Ayse Berkdemir, Bei Wang, Ruitao Lv, Florentino López-Urías, Vincent H. Crespi, Humberto Terrones, Mauricio Terrones

Research output: Contribution to journalArticle

890 Scopus citations

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.

Original languageEnglish (US)
Pages (from-to)3447-3454
Number of pages8
JournalNano letters
Volume13
Issue number8
DOIs
StatePublished - Aug 14 2013

    Fingerprint

All Science Journal Classification (ASJC) codes

  • Bioengineering
  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanical Engineering

Cite this