Controlled Synthesis of 2D Palladium Diselenide for Sensitive Photodetector Applications

Long Hui Zeng, Di Wu, Sheng Huang Lin, Chao Xie, Hui Yu Yuan, Wei Lu, Shu Ping Lau, Yang Chai, Lin Bao Luo, Zhong Jun Li, Yuen Hong Tsang

Research output: Journal article publicationJournal articleAcademic researchpeer-review

156 Citations (Scopus)

Abstract

Palladium diselenide (PdSe2), a thus far scarcely studied group-10 transition metal dichalcogenide has exhibited promising potential in future optoelectronic and electronic devices due to unique structures and electrical properties. Here, the controllable synthesis of wafer-scale and homogeneous 2D PdSe2 film is reported by a simple selenization approach. By choosing different thickness of precursor Pd layer, 2D PdSe2 with thickness of 1.2–20 nm can be readily synthesized. Interestingly, with the increase in thickness, obvious redshift in wavenumber is revealed by Raman spectroscopy. Moreover, in accordance with density functional theory (DFT) calculation, optical absorption and ultraviolet photoemission spectroscopy (UPS) analyses confirm that the PdSe2 exhibits an evolution from a semiconductor (monolayer) to semimetal (bulk). Further combination of the PdSe2 layer with Si leads to a highly sensitive, fast, and broadband photodetector with a high responsivity (300.2 mA W−1) and specific detectivity (≈1013 Jones). By decorating the device with black phosphorus quantum dots, the device performance can be further optimized. These results suggest the as-selenized PdSe2 is a promising material for optoelectronic application.

Original languageEnglish
Article number1806878
JournalAdvanced Functional Materials
Volume29
Issue number1
DOIs
Publication statusPublished - 4 Jan 2019

Keywords

  • broadband photodetectors
  • density functional theory
  • heterojunction
  • photodetectors
  • transitional metal dichalcogenides

ASJC Scopus subject areas

  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics

Cite this