Unraveling the Complex Nanomorphology of Ternary Organic Solar Cells with Multimodal Analytical Transmission Electron Microscopy

S. Rechberger, N. Gasparini, R. Singh, M. Kim, C.L. Chochos, V.G. Gregoriou, K. Cho, C.J. Brabec, T. Ameri, E. Spiecker

Research output: Contribution to journalArticlepeer-review


Elucidating the complex materials distribution in the active layers of ternary organic solar cells is one of the greatest challenges in the field of organic photovoltaics. Knowledge of the nanomorphology is key to understanding photophysical processes (e.g., charge separation, adjustment of the recombination mechanism, and suppression of the radiationless and energetic losses) and thus improving the device performance. Herein, for the first time, the successful discrimination and spatial mapping of the active layer components of a ternary organic solar cell are demonstrated using analytical transmission electron microscopy. The material distribution of all three organic components is successfully visualized by multimodal imaging using complementary electron energy loss signals. A complete picture of the morphological aspects can be gained by studying the lateral and cross-sectional morphology as well as the morphology evolution as a function of the mixing ratio of the polymers. Finally, a correlation between the morphology, photophysical processes, and device performance of the ternary and the reference binary system is achieved, explaining the differences of the power conversion efficiency between the two systems. © 2020 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Original languageEnglish
JournalSolar RRL
Issue number6
Publication statusPublished - 2020


  • Electron energy levels
  • Energy dissipation
  • High resolution transmission electron microscopy
  • Morphology
  • Nanostructured materials
  • Solar power generation
  • Analytical transmission electron microscopy
  • Cross-sectional morphology
  • Material distribution
  • Morphological aspects
  • Organic photovoltaics
  • Photophysical process
  • Power conversion efficiencies
  • Recombination mechanisms
  • Organic solar cells

Fingerprint Dive into the research topics of 'Unraveling the Complex Nanomorphology of Ternary Organic Solar Cells with Multimodal Analytical Transmission Electron Microscopy'. Together they form a unique fingerprint.

Cite this