UCL logo

UCL Discovery

UCL home » Library Services » Electronic resources » UCL Discovery

Ultra-fast spin-mixing in a diketopyrrolopyrrole monomer / fullerene blend charge transfer state

Salvadori, E; Luke, N; Shaikh, J; Leventis, A; Bronstein, H; Kay, C; Clarke, T; (2017) Ultra-fast spin-mixing in a diketopyrrolopyrrole monomer / fullerene blend charge transfer state. Journal of Materials Chemistry A , 5 (46) pp. 24335-24343. 10.1039/C7TA07381J. Green open access

[img]
Preview
Text
Diketopyrrolopyrole_published_JMCA for upload.pdf - ["content_typename_Accepted version" not defined]

Download (820kB) | Preview

Abstract

Diketopyrrolopyrrole (DPP) is one of the most common building blocks for small molecules and conjugated polymers designed for organic electronic applications. By attaining a detailed understanding of the photophysical behaviour for a simple DPP-based molecule in fullerene blends, we establish a foundation for spectroscopic investigations into more complex DPP-based systems. Transient absorption spectroscopy (TAS) and time-resolved electron paramagnetic resonance (TR-EPR) spectroscopy are used to examine bulk heterojunction blend films of a small diketopyrrolopyrrole-based molecule, 2,5-bis(2-hexyldecyl)-3,6-di(thiophen-2-yl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione (TDPP) with the common fullerene derivatives [6,6]-phenyl-C61-butyric acid methyl ester (PC60BM) and [6,6]-phenyl-C71-butyric acid methyl ester (PC70BM). Following pulsed laser excitation, the spectral signatures of a fullerene anion and a TDPP triplet state are observed on the picosecond timescale by TAS. The presence of these species implies the formation of a TDPP:PCBM charge transfer state that subsequently undergoes ultra-fast spin-mixing and geminate recombination to produce a TDPP triplet state. The overall photophysical mechanism is confirmed by TR-EPR spectroscopy, which unambiguously shows that the TDPP triplet is formed via spin-mixing in the TDPP:PCBM charge transfer state, rather than direct intersystem crossing from the excited singlet state.

Type: Article
Title: Ultra-fast spin-mixing in a diketopyrrolopyrrole monomer / fullerene blend charge transfer state
Open access status: An open access version is available from UCL Discovery
DOI: 10.1039/C7TA07381J
Publisher version: http://doi.org/10.1039/C7TA07381J
Language: English
Additional information: © The Royal Society of Chemistry 2017. This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.
UCL classification: UCL > Provost and Vice Provost Offices
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Chemistry
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > London Centre for Nanotechnology
URI: http://discovery.ucl.ac.uk/id/eprint/10039077
Downloads since deposit
60Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item