Efficient Defect Healing of Transition Metal Dichalcogenides by Metallophthalocyanine

Hye Young Ahn*, Yu Chiao Huang, Chang Wei Lin, Yi Lun Chiu, Erh Chen Lin, Ying Yu Lai, Yi Hsien Lee

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

3 Scopus citations

Abstract

Two-dimensional (2D) transition metal dichalcogenides (TMDCs) have attracted great attention as alternatives to graphene with semiconducting band gaps. Mono- or few-layer TMDCs can be prepared by various methods, but regardless of the fabrication methods [such as mechanical exfoliation and chemical vapor deposition (CVD)], TMDCs contain many structural defects, which significantly affect their physical properties and limit their performance in applications. Metallophthalocyanines (MPcs) are organic semiconductors, and as dopants, they are capable of modulating the optical and electrical properties of other semiconducting materials. Here, we report that besides the ability to modulate the optoelectronic properties of 2D TMDCs, MPc molecules can be used to heal defects and improve the physicochemical properties of TMDCs. Doping of planar MPc molecules to TMDCs is achieved by a simple solution dip-coating method and results in a significant improvement in the optical properties and thermal responses of CVD-grown TMDCs, even comparable to those of mechanically exfoliated counterparts. Study of carrier dynamics shows that the adsorption of MPc on the TMDC surface leads to the complete suppression of the mid-gap defect-induced absorption in TMDCs. Furthermore, MPc molecules with a large lateral size are found to effectively reduce the point defects in mechanically exfoliated TMDCs introduced during the preparation process. Our results not only clarify the optoelectronic modulation mechanism of chemical doping but also offer a simple method to control the nanosized defects in 2D TMDCs.

Original languageEnglish
Pages (from-to)29145-29152
Number of pages8
JournalACS Applied Materials and Interfaces
Volume10
Issue number34
DOIs
StatePublished - 29 Aug 2018

Keywords

  • defects
  • molybdenum diselenide
  • phthalocyanine
  • transition metal dichalcogenides
  • two-dimensional materials

Fingerprint Dive into the research topics of 'Efficient Defect Healing of Transition Metal Dichalcogenides by Metallophthalocyanine'. Together they form a unique fingerprint.

Cite this