Work

A Self‐Assembling Molecule for Improving the Mobility in PEDOT:PSS Hole Transport Layer for Efficient Perovskite Light‐Emitting Diodes

Year: 2024

Type: article

Abstract: Poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS), the most widely used hole injection layer (HIL) for perovskite light‐emitting diodes (PeLEDs), has a large hole injection energy barrier and easy charge separation at PEDOT:PSS/perovskite layer. Here, a self‐assembling molecule (SAM) called (2‐(3,6‐dimethoxy‐9H‐carbazol‐9‐yl)ethyl) phosphonic acid (MeO‐2PACz) is introduced as an interlayer between PEDOT:PSS and perovskite to overcome the limitations of PEDOT:PSS HIL. The MeO‐2PACz interlayer facilitated hole injection due to the reduced hole injection energy barrier and the improved hole mobility, enhanced photoluminescence (PL) due to the prevented charge transfer from perovskite into PEDOT:PSS, and reduced interface trap density due to the passivation of methoxy and carbazole group toward perovskite. As a result, PeLEDs with MeO‐2PACz interlayer has greatly enhanced maximum luminance (Lmax = 17,310 cd m−2) and reduced leakage current, resulting in higher maximum external quantum efficiency (EQEmax = 21.50%) compared to pristine Control device (EQEmax of 4.82%).

Source: Advanced Electronic Materials

DOI: 10.1002/aelm.202400626

Authors: Tae Hyung Kim, Bong Woo Kim, Sang Hyuk Im

Institution: Korea University

Language: English

Topic: Perovskite Materials and Applications

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $3,100

Funders: National Research Foundation, Ministry of Science, ICT and Future Planning, National Research Foundation of Korea, Ministry of Science and ICT, South Korea