Jump to main content
Jump to site search

Issue 48, 2017
Previous Article Next Article

Enhancement of efficiency and long-term stability in graphene/Si-quantum-dot heterojunction photodetectors by employing bis(trifluoromethanesulfonyl)-amide as a dopant for graphene

Author affiliations

Abstract

We for the first time employ bis(trifluoromethanesulfonyl)-amide as a dopant for graphene to enhance the efficiency and the stability of graphene/Si quantum dot (SQDs)-embedded SiO2 (SQDs:SiO2) multilayer (ML) heterojunction photodetectors (PDs). With increasing the doping concentration (nD) to 30 mM, the sheet resistance of the doped-graphene transparent conductive electrode (TCE) sharply decreases to ∼155 ohm sq−1 with only 1% reduction in its transmittance at 550 nm, whilst the work function gradually increases to ∼4.95 eV, indicating p-type doping, useful for the graphene/SQDs:SiO2 MLs interface. The DC conductivity/optical conductivity ratio saturates to ∼75 at nD = 20 mM, much larger than the minimum industry standard (= 35) for the optoelectronic applications of TCEs. The PDs optimized at nD = 20 mM exhibit 0.413 A W−1 responsivity (R), 92 dB linear dynamic range, 1.09 × 1010 cm Hz1/2 W−1 detectivity, and 81.33% external quantum efficiency at a peak wavelength of 630 nm, and the loss of R is almost negligible while the PDs are kept for 700 h in air. These characteristics are comparable to those of commercially-available Si PDs and better than those of previously-reported graphene/Si PDs.

Graphical abstract: Enhancement of efficiency and long-term stability in graphene/Si-quantum-dot heterojunction photodetectors by employing bis(trifluoromethanesulfonyl)-amide as a dopant for graphene

Back to tab navigation

Supplementary files

Publication details

The article was received on 12 Oct 2017, accepted on 18 Nov 2017 and first published on 18 Nov 2017


Article type: Paper
DOI: 10.1039/C7TC04647B
Citation: J. Mater. Chem. C, 2017,5, 12737-12743
  •   Request permissions

    Enhancement of efficiency and long-term stability in graphene/Si-quantum-dot heterojunction photodetectors by employing bis(trifluoromethanesulfonyl)-amide as a dopant for graphene

    D. H. Shin, C. W. Jang, J. H. Kim, J. M. Kim, H. S. Lee, S. W. Seo, S. Kim and S. Choi, J. Mater. Chem. C, 2017, 5, 12737
    DOI: 10.1039/C7TC04647B

Search articles by author

Spotlight

Advertisements