3D Electron Diffraction -- The Missing Slice for a Complete Nanoscale Analysis of Organic Solar Cells in TEM

Irene Kraus; Mingjian Wu; Stefanie Rechberger; Johannes Will; Santanu Maiti; Konstantin Dengel; Andreas Kuhlmann; Marten Huck; Larry Lüer; Florian Bertram; Hans-Georg Steinrück; Tobias Unruh; Christoph J. Brabec; Erdmann Spiecker

arXiv · 2502.11254

3D Electron Diffraction -- The Missing Slice for a Complete Nanoscale Analysis of Organic Solar Cells in TEM

Irene Kraus·Mingjian Wu·Stefanie Rechberger·Johannes Will·Santanu Maiti·Konstantin Dengel·Andreas Kuhlmann·Marten Huck·Larry Lüer·Florian Bertram·Hans-Georg Steinrück·Tobias Unruh·Christoph J. Brabec·Erdmann Spiecker

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Abstract

Optimizing the performance of organic solar cells (OSCs) hinges on a comprehensive understanding of their nanostructures, yet traditional characterization methods often fall short, delivering incomplete structural snapshots. We introduce elastically filtered 3D Electron Diffraction (3D ED) as a ground-breaking technique bridging full reciprocal- and real-space structural analysis within a single transmission electron microscope (TEM). Using solvent-vapor annealed DRCN5T:PC71BM, 3D ED reproduces key structural parameters from GIWAXS including lattice spacings, coherence lengths, and mosaicity, while uniquely delivering true in-plane access and direct registration with high-resolution imaging, diffraction imaging and nano-spectroscopy on the same sample. A low-dose, distributed tilt strategy plus energy filtering yields high signal-to-background below damage thresholds. Extension to a second archetypal blend (P3HT:PC71BM; annealing evolution) demonstrates generality. Our findings underscore the transformative potential of 3D ED, particularly in analysing beam-sensitive organic thin films. This paves the way for new avenues in advanced correlative structural characterization of OSCs and holds potential for application to a multitude of other nanostructured materials.

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Irene Kraus, Mingjian Wu, Stefanie Rechberger, Johannes Will, Santanu Maiti, Konstantin Dengel, Andreas Kuhlmann, Marten Huck, Larry Lüer, Florian Bertram, Hans-Georg Steinrück, Tobias Unruh, Christoph J. Brabec, Erdmann Spiecker. 2026-01-10. 3D Electron Diffraction -- The Missing Slice for a Complete Nanoscale Analysis of Organic Solar Cells in TEM. https://arxiv.org/abs/2502.11254

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