Finally, inkjet-printed metal halide perovskite LEDs-utilizing seed crystal templating of salty PEDOT:PSS

Research output: Contribution to journalArticle


Solution-processable metal halide perovskites are increasingly implemented in perovskite-based light-emitting diodes (PeLEDs). Especially green PeLEDs based on methylammonium lead bromide (MAPbBr3) composites exhibit impressive optoelectronic properties, while allowing processing by low-cost and upscalable printing methods. In this study, we have investigated the influence of potassium chloride (KCl) blended into the common hole injection material poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) to boost PeLED device performance. The inclusion of KCl firstly results in a change in morphology of the PEDOT:PSS layer, which then acts as a template during deposition of the perovskite layer. A MAPbBr3:polyethylene glycol (PEG) composite was used, which does not require the deposition of an anti-solvent droplet to induce preferential perovskite crystallization and is therefore suitable for spin coating and scalable inkjet printing processes. PeLEDs utilizing the KCl induced templating effect on a planar PEDOT:PSS/MAPbBr3:PEG architecture show improved performance, predominantly due to improved crystallization. PeLEDs incorporating spin-coated perovskite layers yield a 40-fold increase in luminance (8000 cd m-2) while the turn-on voltage decreases to 2.5 V. KCl-modified PEDOT:PSS contact layers enabled the realization of inkjet-printed PeLEDs with luminance increased by a factor of 20 at a maximum of 4000 cd m-2 and a turn-on voltage of 2.5 V. This work paves the way for inkjet-printed perovskite light-emitting devices for a wide variety of low-cost and customizable applications. This journal is


  • Felix Hermerschmidt
  • Florian Mathies
  • Vincent R.F. Schröder
  • Carolin Rehermann
  • Nicolas Zorn Morales
  • Eva L. Unger
  • Emil J.W. List-Kratochvil
External organisations
  • Humboldt University of Berlin
  • Helmholtz-Zentrum Berlin for Materials and Energy
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Materials Chemistry
Original languageEnglish
Pages (from-to)1773-1781
Number of pages9
JournalMaterials Horizons
Issue number7
Publication statusPublished - 2020
Publication categoryResearch