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2026 Vol.14, Issue 1
Conjugated Oligoelectrolyte Ligands for CsPbBr3 Nanocrystals: Impact of Ionic Density on Förster Energy Transfer
Jung Min Ha1
,
Nayoung Kim1
,
Ha Yeon Kim1
,
Sungnam Park1
,
Han Young Woo1*
1Department of Chemistry, Korea University, Seoul, 02841, Korea
*Corresponding Author
31 March 2026. pp. 1-8
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Abstract

Replacing insulating aliphatic ligands with conjugated oligoelectrolytes (COEs) enables strong binding, effective passivation, and Förster resonance energy transfer (FRET) to amplify the fluorescence of CsPbBr3 perovskite nanocrystals (PNCs). Herein, we report multifunctional COEs with systematically varied ionic densities (2, 4, and 6 quaternary ammonium bromides) as surface ligands for CsPbBr3 PNCs. Increasing ionic density enhances binding intimacy with the PNC surface, leading to photoluminescence quantum yield (PLQY) over 94% with more efficient FRET efficiency. Time-resolved photoluminescence reveals FRET efficiencies of 40%, 63%, and 84% for QTF2Br, QTF4Br, and QTF6Br-capped PNCs, respectively. While higher ionic densities achieve superior FRET performance, they compromise colloidal dispersibility due to increased surface polarity. The study provides molecular-level insights into how ionic density modulates interfacial coupling and affects the luminescent property of PNCs, offering design principles of semiconducting ligands and unleash their potential for their optoelectronic applications.

Keywords
Perovskite nanocrystals
Conjugated oligoelectrolytes
Förster energy transfer
Surface ligands
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Information
  • Publisher :Korea Photovoltaic Society
  • Publisher(Ko) :한국태양광발전학회
  • Journal Title :Current Photovoltaic Research
  • Volume : 14
  • No :1
  • Pages :1-8
  • Received Date : 2025-09-10
  • Revised Date : 2025-11-11
  • Accepted Date : 2025-11-14
  • DOI :https://doi.org/10.21218/CPR.2026.14.1.001
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