Jump to main content
Jump to site search

Issue 3, 2018
Previous Article Next Article

Ambipolar charge transport in a bis-diketopyrrolopyrrole small molecule semiconductor with tunable energetic disorder

Author affiliations

Abstract

Energetic disorder and activation energy are important parameters that influence the charge carrier mobility in organic semiconductors. Herein, we investigate temperature-dependent ambipolar charge transport alongside its thermal activation energy in organic field-effect transistors (OFETs) based on a diketopyrrolopyrrole (DPP) based small molecule BTDPP2. The determined energetic disorder in BTDPP2 is analogous to those of highly crystalline molecules, such as pentacene, while lower than those of widely used fullerene derivatives (PCBM) or semi-crystalline polymers, such as P3HT. We demonstrate that the energetic disorder and activation energy in BTDPP2 are both impacted by the crystallinity, which is tuned by thermal annealing; moreover, to a certain extent, these two parameters can reduce with increasing the structural order. Moreover, the energetic disorder tends to decrease when BTDPP2 is subjected to thermal annealing. Through comparing the electron transport in BTDPP2 based OFETs and vertical diodes, in which the electron densities differentiate substantially, the different activation energies are roughly described in terms of achievable carrier densities in these two devices. To the best of our knowledge, this aspect has not been addressed on the electron transport in molecular semi-conductive materials. Our results shine light on fundamental understandings of charge transport properties in solution processed small molecules holding promise for opto-electronic applications.

Graphical abstract: Ambipolar charge transport in a bis-diketopyrrolopyrrole small molecule semiconductor with tunable energetic disorder

Back to tab navigation

Supplementary files

Publication details

The article was received on 15 Nov 2017, accepted on 08 Dec 2017 and first published on 11 Dec 2017


Article type: Paper
DOI: 10.1039/C7CP07708D
Citation: Phys. Chem. Chem. Phys., 2018,20, 1787-1793
  •   Request permissions

    Ambipolar charge transport in a bis-diketopyrrolopyrrole small molecule semiconductor with tunable energetic disorder

    J. Zhou, S. Bi, S. Yang, H. Zhou and Y. Zhang, Phys. Chem. Chem. Phys., 2018, 20, 1787
    DOI: 10.1039/C7CP07708D

Search articles by author

Spotlight

Advertisements