Mixing in PCBM/P3HT bilayers, using in situ and ex situ neutron reflectivity

DOI: 10.1557/jmr.2017.59

Authors: Dyfrig Mon (Swansea University) , Anthony M. Higgins (Swansea University) , Philipp Gutfreund (Institut Laue-Langevin) , David James (Swansea University)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Journal Of Materials Research , VOL 32 , PAGES 1946 - 1956

State: Published (Approved)
Published: May 2017
Diamond Proposal Number(s): 1519

Abstract: In situ and ex situ neutron reflectivity is used to characterize annealed regioregular-P3HT/PCBM bilayers. In situ annealing of a 20 nm PCBM/35 nm P3HT bilayer at 170 °C reveals rapid mixing of PCBM and P3HT to produce a polymer-rich layer that contains around 18–20% PCBM. Samples with three different thicknesses of P3HT layer are ex situ annealed at 140 °C. This again reveals migration of PCBM into the P3HT and vice versa, with the polymer-rich layer in the 20 nm PCBM/35 nm P3HT sample containing 19% PCBM. Complete migration of the entire PCBM layer into the P3HT layer is observed for a 20 nm PCBM/80 nm P3HT bilayer. The robustness of fitted model composition profiles, in comparison with real-space imaging of sample surface morphology and previous work on annealed P3HT/PCBM bilayer compositions, is discussed in detail.

Diamond Keywords: Photovoltaics; Semiconductors

Subject Areas: Physics, Materials, Chemistry


Instruments: I07-Surface & interface diffraction

Added On: 07/09/2017 16:36

Documents:
mixing_in_pcbmp3ht_bilayers_using_in_situ_and_ex_situ_neutron_reflectivity.pdf

Discipline Tags:

Surfaces Earth Sciences & Environment Sustainable Energy Systems Energy Physics Climate Change Physical Chemistry Energy Materials Chemistry Materials Science interfaces and thin films

Technical Tags:

Diffraction Grazing Incidence X-ray Diffraction (GIXD)