p-π conjugated polyelectrolyte with simultaneously enhanced work function and conductivity for efficient organic optoelectronics

The development of non-corrosive and efficient anode interlayers (AILs) is pivotal for advancing high-performance organic optoelectronic devices. Conventional materials such as PEDOT:PSS, though widely adopted, suffer from significant limitations including acidity, corrosion, and poor device stability. Herein, we propose a novel molecular design strategy by introducing p-π conjugation into a pH-neutral conjugated polyelectrolyte (CPE) (PIDT-T) to simultaneously enhance work function (WF) and electrical conductivity. Through doping with polyoxometalate (POM), the optimized PIDT-T:POM achieves a high WF of 4.85 eV, conductivity of 7.25×10−3 S cm−1, and >98% optical transmittance. In organic solar cells (OSCs), PIDT-T:POM delivers a power conversion efficiency (PCE) of 19.04%, outperforming PEDOT:PSS-based counterparts (18.52%) and representing one of the highest PCEs reported for devices utilizing non-acidic AILs. Moreover, organic light-emitting diodes (OLEDs) incorporating PIDT-T:POM exhibit a remarkable reduction in turn-on voltage (from 5.8 to 3.0 V) and enhanced luminous efficiency, demonstrating its dual functionality for both OSCs and OLEDs. These findings establish p-π conjugated polyelectrolytes as a powerful molecular platform for next-generation, high-efficiency, and corrosion-free organic optoelectronic applications.