Efficient and spectrally stable blue perovskite light-emitting diodes employing a cationic π-conjugated polymer

DOI: 10.1002/adma.202103640

Authors: Shuai Yuan (Soochow University; University of Science and Technology of China) , Lin-Song Cui (University of Science and Technology of China; University of Cambridge) , Linjie Dai (University of Cambridge) , Yun Liu (University of Cambridge) , Qing-Weii Liu (Soochow University) , Yu-Qi Sun (University of Cambridge) , Florian Auras (University of Cambridge) , Miguel Anaya (University of Cambridge) , Xiaopeng Zheng (King Abdullah University of Science and Technology (KAUST)) , Edoardo Ruggeri (University of Cambridge) , You-Jun Yu (Soochow University) , Yang-Kun Qu (Soochow University) , Mojtaba Abdi-Jalebi (University of Cambridge) , Osman M. Bakr (King Abdullah University of Science and Technology (KAUST)) , Zhao-Kui Wang (Soochow University) , Samuel D. Stranks (University of Cambridge) , Neil C. Greenham (University of Cambridge) , Liang-Sheng Liao (Soochow University) , Richard H. Friend (University of Cambridge)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Advanced Materials , VOL 13

State: Published (Approved)
Published: September 2021
Diamond Proposal Number(s): 17223

Abstract: Metal halide perovskite semiconductors have demonstrated remarkable potentials in solution-processed blue light-emitting diodes (LEDs). However, the unsatisfied efficiency and spectral stability responsible for trap-mediated non-radiative losses and halide phase segregation remain the primary unsolved challenges for blue perovskite LEDs. In this study, it is reported that a fluorene-based π-conjugated cationic polymer can be blended with the perovskite semiconductor to control film formation and optoelectronic properties. As a result, sky-blue and true-blue perovskite LEDs with Commission Internationale de l'Eclairage coordinates of (0.08, 0.22) and (0.12, 0.13) at the record external quantum efficiencies of 11.2% and 8.0% were achieved. In addition, the mixed halide perovskites with the conjugated cationic polymer exhibit excellent spectral stability under external bias. This result illustrates that π-conjugated cationic polymers have a great potential to realize efficient blue mixed-halide perovskite LEDs with stable electroluminescence.

Journal Keywords: blue emissions; high efficiencies; ion migrations; perovskite light- emitting diodes; stabilities

Diamond Keywords: Light-Emitting Diodes (LEDs); Semiconductors

Subject Areas: Materials, Chemistry, Physics


Instruments: I07-Surface & interface diffraction

Added On: 27/09/2021 13:45

Discipline Tags:

Surfaces Physics Physical Chemistry Electronics Energy Materials Chemistry Materials Science Perovskites Metallurgy

Technical Tags:

Scattering Wide Angle X-ray Scattering (WAXS) Grazing Incidence Wide Angle Scattering (GIWAXS)