Structural Nanoprobes of Organic Semiconductor Devices
Lead Research Organisation:
University of Cambridge
Department Name: Physics
Abstract
Organic semiconductors are an exciting new class of material that combine the electronic properties traditionally only associated with inorganic materials, with the mechanical properties and processibility of polymers (plastics) and small organic molecules. In particular, the ability to process active semiconductor layers through solution processing has led to the commercialisation of organic light-emitting diode-based displays. Commercial potential has also been demonstrated by organic transistors and organic solar cells, where both technologies have the advantage of low-cost processing and the ability to be incorporated into flexible architectures.However, as organic semiconductors are a relatively new class of material, there are still many fundamental questions governing key processes that affect device performance. For example, organic semiconductor films are typically less ordered than their inorganic counterparts and the influence of domain structure, molecular orientation and molecular alignment on charge transport is not fully understood. Additionally, for organic solar cells, where typically two different materials are blended together to form efficient networks for charge separation and transport, the influence of material mixing on charge separation and transport are still being discovered.Since organic semiconductors have vastly different properties compared to inorganic semiconductors, the development and application of new techniques to probe the properties of this new class of material is required. This research programme will adapt state-of-the-art microscopes and utilize advanced X-ray analytical techniques to probe structure and device action in organic devices with unprecedented precision and clarity. This further understanding of device operation will allow for the identification of physical processes that limit device performance and hence promote future device optimisation.
Publications
Gwinner MC
(2012)
Highly efficient single-layer polymer ambipolar light-emitting field-effect transistors.
in Advanced materials (Deerfield Beach, Fla.)
GĂ©linas S
(2011)
The Binding Energy of Charge-Transfer Excitons Localized at Polymeric Semiconductor Heterojunctions
in The Journal of Physical Chemistry C
He X
(2014)
Influence of Fluorination and Molecular Weight on the Morphology and Performance of PTB7:PC 71 BM Solar Cells
in The Journal of Physical Chemistry C
He X
(2012)
Studying polymer/fullerene intermixing and miscibility in laterally patterned films with X-ray spectromicroscopy.
in Small (Weinheim an der Bergstrasse, Germany)
Hwang I
(2014)
Evolution of phase separation upon annealing and the influence on photocurrent generation in ternary blend organic solar cells
in Synthetic Metals
Hwang I
(2009)
Drift-diffusion modeling of photocurrent transients in bulk heterojunction solar cells
in Journal of Applied Physics
Li Z
(2011)
Comparison of the Operation of Polymer/Fullerene, Polymer/Polymer, and Polymer/Nanocrystal Solar Cells: A Transient Photocurrent and Photovoltage Study
in Advanced Functional Materials
Li Z
(2011)
Transient photocurrent measurements of PCDTBT:PC70BM and PCPDTBT:PC70BM Solar Cells: Evidence for charge trapping in efficient polymer/fullerene blends
in Journal of Applied Physics
Li Z
(2013)
Voltage-dependent photocurrent transients of PTB7:PC70BM solar cells: Experiment and numerical simulation
in Journal of Applied Physics
Marsh RA
(2008)
A unified description of current-voltage characteristics in organic and hybrid photovoltaics under low light intensity.
in Nano letters
Description | This EPSRC Advanced Fellowship for Dr Chris McNeill allowed him to develop a series of advanced structural probes, including synchrotron-based techniques, for characterisation of the microstructure of polymer electronics devices, particularly transistors and solar cells. Combined with device physics studies, this work has furthered our understanding of charge transport and photophysics relevant to improving device performance. |
Exploitation Route | The work will inform the optimisation of practical organic electronic devices, and provides structural probes that are of interest to researchers in other fields. |
Sectors | Electronics,Energy |
Description | The findings have assisted in the optimisation of polymer solar cells and transistors, accelerating their commercial application. |
First Year Of Impact | 2010 |
Sector | Electronics,Energy |
Impact Types | Economic |