Controlled Morphology of ZnO Nanorods for Electron Transport in Squaraine Bulk-Hetero Junction Solar Cells With Thick Active Layers

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Andreas Peukert - , Vrije Universiteit Amsterdam (VU) (Author)
  • Lidice Vaillant Roca - , University of Havana (Author)
  • Michael Scherer - , InnovationLab GmbH, Technical University of Braunschweig (Author)
  • Robert Lovrincic - , InnovationLab GmbH, Technical University of Braunschweig (Author)
  • Charusheela Ramanan - , Vrije Universiteit Amsterdam (VU) (Author)
  • Alina Chanaewa - , Vrije Universiteit Amsterdam (VU) (Author)
  • Elizabeth von Hauff - , Vrije Universiteit Amsterdam (VU) (Author)

Abstract

The influence of ZnO seed layer thickness in Squaraine (SQ) is investigated: PC71BM bulk heterojunction solar cells that incorporate ZnO nanorods. The thickness of the ZnO seed layer varies between 16–249 nm by changing the concentration of the precursor solution. With atomic force microscopy (AFM), X-Ray Diffraction (XRD), and Scanning Electron Microscopy (SEM) studies, it is shown that this approach allows to systematically tune the thickness of the ZnO seed layer without influencing seed layer grain size, or the morphology of the ZnO nanorods that are deposited on top of the seed layer. The proof-of-concept is demonstrated in SQ:PC71BM solar cells. It is found that seed layers with 55 nm thickness yield the highest short circuit current densities, resulting in power conversion efficiencies of 2.5 ± 0.1%. These results are compared to SQ:PC71BM solar cells prepared in planar architectures, and it is observed that both device architectures yield comparable results. The optimized nanostructured ZnO electrode enables the fabrication of BHJ devices with thick active layers without the loss in solar cell performance.

Details

Original languageEnglish
Article number1700132
JournalSolar RRL
Volume1
Issue number12
Publication statusPublished - 1 Dec 2017
Peer-reviewedYes
Externally publishedYes