Tailoring hole transport polymers with substituent control for green perovskite LEDs with increased luminance and reduced efficiency roll-off

• Published in: Macromolecular research Vol. 33; no. 6; pp. 767 - 777
• Main Authors: Park, Chanbin, Cho, Young Seo, Kim, Gwang-il, Mo, Yurim, Lee, Seon Joo, Na, Hyejin, Choi, Sungho, Lee, Jaemin
• Format: Journal Article
• Language: English
• Published: Seoul The Polymer Society of Korea 01.06.2025; Springer Nature B.V; 한국고분자학회
• Subjects: Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Complex Fluids and Microfluidics; Electrical properties; Light emitting diodes; Luminance; Nanochemistry; Nanotechnology; Optical properties; Perovskites; Photoluminescence; Physical Chemistry; Polymer Sciences; Polymers; Soft and Granular Matter; 고분자공학; Fluorene; Perovskite; LED; Arylamine; Suzuki polymerization
• ISSN: 1598-5032; 2092-7673
• DOI: 10.1007/s13233-024-00364-5

Despite rapid advancements in the field of perovskite light-emitting diodes (Pe-LEDs), research on polymer hole transport materials (HTMs), a key component of these devices, remains limited. In this study, we developed two new polymer HTMs by substituting the sec -butyl group in the triphenylamine moiety of poly[(9,9-dioctylfluorenyl-2,7-diyl)- co -(4,4′-(N-(4- sec -butylphenyl)diphenylamine)] (TFB) with either an SCH 3 or OCH 3 group, resulting in OctSMe or OctOMe, respectively. The optical and electrical properties of these new HTMs were thoroughly characterized by various methods. When incorporated into green Pe-LED devices, the new HTMs achieved over 1.6 times higher luminance and a 10–20% reduction in efficiency roll-off compared to the reference TFB, attributed to smoother hole injection and improved energy-level alignment. These enhancements in device performance were further supported by hole-only device experiments and time-resolved photoluminescence analysis. Additionally, devices with the new HTMs demonstrated longer lifetimes than those with TFB, underscoring their potential as effective alternatives in Pe-LED applications. Graphic Abstract We developed two new polymer HTMs, OctSMe and OctOMe, by replacing the sec -butyl group in TFB with SCH 3 or OCH 3 . In green Pe-LEDs, these HTMs achieved over 1.6 times higher luminance and a 10–20% reduction in efficiency roll-off compared to TFB, due to improved hole injection and energy alignment. Hole-only device tests and time-resolved photoluminescence analysis supported these gains, along with longer lifetimes, suggesting potential as TFB alternatives.