The Quest for Air Stability in Organic Semiconductors

Organic semiconductors (OSCs) have emerged as promising materials for a variety of organic electronic devices due to their unique combination of electrical conductivity, mechanical flexibility, and processability. Despite significant advancements in the performance and functionalities of organic devices, their widespread adoption stems from challenges in long-term operational stability and sensitivity to moisture and oxygen in ambient air. Although several reviews in respective fields of organic electronic devices highlight the role of molecular structure in optimizing device performance, a unified picture to achieve long-term air stability of these devices is still lacking. To this end, this review provides an in-depth thermodynamic consideration of the redox reactions involving ambient species and pristine or doped OSCs that limit the operational stability of their corresponding devices in air. This review also explores recent advancements in both polymer and dopant design and rationalizes the commonalities of molecular design that drive the development of air-stable conducting polymers for various organic electronic applications. The insights presented in this review contribute to the understanding of the critical role played by air-stable conducting polymers in the realization of reliable and commercially viable organic electronic devices.