Jump to main content
Jump to site search


The engineering of stilbazolium/iodocuprate hybrids with optical/electrical performances by modulating inter-molecular charge transfer among H-aggregated chromophores

Author affiliations

Abstract

The combination of D–π-A stilbazolium-type chromophores bearing ortho-N-alkyl substituents with iodocuprate resulted in three novel hybrids, these were, [(CMAMP)2(CuI3)(acetone)0.5]n (1), [(HMAMP)(Cu3I4)]n (2), and [(HMAHP)2(Cu5I7)]n (3), which present natural quantum-well architectures with void spaces of quasi-2-D organic layers occupied by iodocuprate anions via C–H⋯I hydrogen bonds. The D–π-A stilbazolium dyes exhibit head-to-tail arranged H-aggregations with face-to-face π⋯π stacking interactions. Theoretical calculations suggest that the charge densities on the benzenes can be strengthened from the electron-withdrawing group (–CN) to the electron-donating group (–OH), and the –C2H5OH substituents on the ortho-N of the pyridines not only help to open up the band gaps, but also provide a steric effect for better face-to-face π⋯π stacking interactions. Therefore, HMAHP+ in 3 possesses the strongest face-to-face π⋯π stacking interactions owing to the presence of a longer –C2H5OH group in the ortho-N position, and consequently, blue-shifted photoluminescence, a stronger photocurrent (0.28 mA), and a higher ON/OFF ratio (1.6 × 104) can be observed in 3. In particular, electrical bistability performances can be observed in ITO/hybrids/poly (methyl methacrylate) (PMMA)/Ag devices, which are explained using Schottky emission, space-charge-limited current effect (SCLC) and Ohmic mechanisms. According to theoretical calculations, the band gap switching from the semi-conductor to the conductor (high resistance state (HRS) to low resistance state (LRS)) after trapping electrons is exclusively dominated by the π bonding and anti-bonding orbitals of the stilbazolium dyes, which indicates a future direction for the design of stilbazolium-containing memory devices.

Graphical abstract: The engineering of stilbazolium/iodocuprate hybrids with optical/electrical performances by modulating inter-molecular charge transfer among H-aggregated chromophores

Back to tab navigation

Supplementary files

Article information


Submitted
24 Dec 2019
Accepted
07 Feb 2020
First published
10 Feb 2020

Inorg. Chem. Front., 2020, Advance Article
Article type
Research Article

The engineering of stilbazolium/iodocuprate hybrids with optical/electrical performances by modulating inter-molecular charge transfer among H-aggregated chromophores

W. Wu, X. Lin, Q. Liu, Y. He, Y. Huang, B. Chen, H. Li and Z. Chen, Inorg. Chem. Front., 2020, Advance Article , DOI: 10.1039/C9QI01672D

Social activity

Search articles by author

Spotlight

Advertisements