Journal article
Tailoring exciton diffusion and domain size in photovoltaic small molecules by annealing
MT Sajjad, Y Zhang, PB Geraghty, VD Mitchell, A Ruseckas, O Blaszczyk, DJ Jones, IDW Samuel
Journal of Materials Chemistry C | ROYAL SOC CHEMISTRY | Published : 2019
DOI: 10.1039/c9tc00951e
Abstract
Exciton diffusion is an important part of light harvesting in organic photovoltaics (OPVs) because it enables excitons to reach the interface between donor and acceptor and contribute to the photocurrent. Here we used simple and cost-effective techniques of thermal annealing and solvent vapour annealing to increase the exciton diffusion coefficient and exciton diffusion length in two liquid crystalline electron donor materials BQR and BTR. We found that the three-dimensional exciton diffusion length increased to ∼40 nm upon annealing in both materials. Grazing-incidence wide angle X-ray scattering (GIWAXS) measurements show an increase of crystallite size to ∼37 nm in both materials after th..
View full abstractGrants
Awarded by Australian Renewable Energy Agency
Funding Acknowledgements
We acknowledge support from the European Research Council (grant 321305). We are grateful to EPSRC for equipment grant (EP/L017008/1) and for support of OB (EP/M508214/1). This work was made possible by support from the Australian Renewable Energy Agency which funds the project grants within the Australian Centre for Advanced Photovoltaics (AUSIAPV/ACAP). Responsibility for the views, information or advice expressed herein is not accepted by the Australian Government. We acknowledge the SAXS/WAXS beamline at the Australian Synchrotron. The research data supporting this publication can be accessed at 10.17630/10fd3801-b282-42c9-b672-750f8d1bb635.