Hybrid phthalocyanine/lead sulphide nanocomposite for bistable memory switches

Khozaee, Zahra, Sosa Vargas, Lydia, Cammidge, Andrew N., Cook, Michael J. and Ray, Asim K. (2015) Hybrid phthalocyanine/lead sulphide nanocomposite for bistable memory switches. Materials Research Express, 2 (9). ISSN 2053-1591

[img]
Preview
PDF (Mat_Res_Exp_manuscript_IOP final sub version) - Submitted Version
Download (2MB) | Preview

Abstract

Asimple, one-step method is employed to produce, at room temperature, a single layer of an organicinorganic nanocomposite containing non-aggregated lead sulphide (PbS) quantum dots (QDs) embedded in a 130 nmthick solution processed film of the organic semiconductor 6PcH2 (metal-free, non-peripherally substituted octahexyl phthalocyanine) on indium tin oxide. The mean size of PbS QDs is found from x-ray diffraction and transmission electron microscopy techniques to be much smaller than the Bohr radius. Further evidence of the quantum confinement effect is provided by a blue shift in the absorption spectrum and the increased band gap of 1.95 eV with respect to bulk PbS. The current–voltage characteristics of the hybrid and pristine 6PcH2 films, both in a sandwich configuration with the aluminium top electrode, exhibit bistable switching type hysteresis. The on-off ratio of the nanocomposite device is at least three orders of magnitude higher than that for 6PcH2 organic films, while both devices operate at a very low bias voltage of 0.5 V. The inclusion of the PbS QDs into the 6PcH2 film enhances the conductivity by nearly two orders of magnitude over that of a comparable pristine 6PcH2 film due to the formation of a charge transfer complex with PbS QDs and 6PcH2 acting as acceptors and donors of electrons, respectively.

Item Type: Article
Additional Information: Citation: Zahra Khozaee et al 2015 Mater. Res. Express 2 096305
Uncontrolled Keywords: phthalocyanines,organic electronics
Faculty \ School: Faculty of Science > School of Chemistry
Depositing User: Pure Connector
Date Deposited: 21 Sep 2015 16:52
Last Modified: 22 Jul 2020 00:24
URI: https://ueaeprints.uea.ac.uk/id/eprint/54457
DOI: 10.1088/2053-1591/2/9/096305

Actions (login required)

View Item View Item