Phosphine oxide modulator-ameliorated hole injection for blue perovskite light-emitting diodes

Journal article

Despite the enormous developments in perovskite light-emitting diodes (PeLEDs) recently, obtaining efficient blue PeLEDs is still considered a critical challenge due to the non-radiative recombination and unbalanced charge injection caused by the unmatched carrier mobility and the deep hole-injection barrier between the hole-transport layer (HTL) and the emissive layer (EML). Herein, we incorporate tris(4-trifluoromethylphenyl)phosphine oxide (TMFPPO), obtained through a facile oxidation synthesis process, into poly(9-vinylcarbazole) (PVK). TMFPPO incorporation modulated the energy level and hole mobility of the binary-blend HTLs to eliminate the hole-injection barrier and balance the charge injection within the EML. Consequently, the blue PeLEDs with blended HTL presented an external quantum efficiency (EQE) of 7.23% centred at 477 nm, which was much higher than the EQE of a PVK device (4.95%). Our results demonstrate that modulating the energy level and charge injection of the HTL in the device is a promising method for obtaining efficient blue PeLEDs.

Authors: Fan, X; Wang, Y; Shen, X; Yu, Z; Jeong, WH

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Royal Society of Chemistry
• Journal: Journal of Materials Chemistry A
• Volume: 11
• Issue: 38
• Pages: 20808-20815
• Publication date: 2023-09-20
• Acceptance date: 2023-09-04
• DOI: 10.1039/d3ta03910b
• EISSN: 2050-7496
• ISSN: 2050-7488
• Language: English