Publication detail

Nanoscale mapping by electron energy-loss spectroscopy reveals evolution of organic solar cell contact selectivity

Antonio Guerrero, Martin Pfannmöller, Alexander Kovalenko, Teresa S. Ripolles, Hamed Heidari, Sara Bals, Louis-Dominique Kaufmann, Juan Bisquert, Germà Garcia-Belmonte

Original Title

Nanoscale mapping by electron energy-loss spectroscopy reveals evolution of organic solar cell contact selectivity

Type

journal article in Web of Science

Language

English

Original Abstract

Organic photovoltaic (OPV) devices are on the verge of commercialization being long-term stability a key challenge. Morphology evolution during lifetime has been suggested to be one of the main pathways accounting for performance degradation. There is however a lack of certainty on how specifically the morphology evolution relates to individual electrical parameters on operating devices. In this work a case study is created based on a thermodynamically unstable organic active layer which is monitored over a period of one year under non-accelerated degradation conditions. The morphology evolution is revealed by compositional analysis of ultrathin cross-sections using nanoscale imaging in scanning transmission electron microscopy (STEM) coupled with electron energy-loss spectroscopy (EELS). Additionally, devices are electrically monitored in real-time using the non-destructive electrical techniques capacitance–voltage (C–V) and Impedance Spectroscopy (IS). By comparison of imaging and electrical techniques the relationship between nanoscale morphology and individual electrical parameters of device operation can be conclusively discerned. It is ultimately observed how the change in the cathode contact properties occurring after the migration of fullerene molecules explains the improvement in the overall device performance.

Keywords

Organic photovoltaics; Degradation; Shelf life; Morphology evolution; Contact selectivity; Low-energy-loss electron spectroscopic imaging

Authors

Antonio Guerrero, Martin Pfannmöller, Alexander Kovalenko, Teresa S. Ripolles, Hamed Heidari, Sara Bals, Louis-Dominique Kaufmann, Juan Bisquert, Germà Garcia-Belmonte

RIV year

2014

Released

15. 11. 2014

Publisher

Elsevier

Location

NZ

ISBN

1566-1199

Periodical

ORGANIC ELECTRONICS

Year of study

2015

Number

16

State

Kingdom of the Netherlands

Pages from

227

Pages to

233

Pages count

7

URL

http://www.sciencedirect.com/science/article/pii/S1566119914005102

BibTex

@article{BUT111067,
  author="Alexander {Kovalenko}",
  title="Nanoscale mapping by electron energy-loss spectroscopy reveals evolution of organic solar cell contact selectivity",
  journal="ORGANIC ELECTRONICS",
  year="2014",
  volume="2015",
  number="16",
  pages="227--233",
  doi="10.1016/j.orgel.2014.11.007",
  issn="1566-1199",
  url="http://www.sciencedirect.com/science/article/pii/S1566119914005102"
}