PbS Colloidal Quantum Dots for Optoelectronics: From Fundamentals to Carrier Transport Strategies and Emerging Applications

ABSTRACT Colloidal quantum dots (CQDs) have been widely adopted in optoelectronics due to their solution‐processability, size‐tunable bandgaps, and excellent optoelectronic properties. Among them, PbS CQDs have emerged as a promising candidate for next‐generation infrared optoelectronics because of their pronounced quantum confinement, broadly tunable optical absorption across most of the short‐wave infrared (SWIR) region, and the potential for multiple exciton generation (MEG). Herein, the recent progress in PbS CQDs for optoelectronics is systematically reviewed. First, the fundamentals of CQDs, including quantum confinement and size‐dependent bandgaps, representative synthesis routes and ligand exchange methods, and thin‐film assembly strategies are summarized. Then, charge carrier management strategies, including surface chemical modification, band alignment design, and interface engineering, are discussed to mitigate carrier transport limitations and improve device performance. Furthermore, recent advances in PbS CQD optoelectronics are presented, covering quantum dot light‐emitting diodes (QLEDs), solar cells, photodetectors, and emerging optoelectronic devices, with emphasis on device architectures, performance optimization, and practical implementations. Finally, a brief conclusion and outlook for future research directions of PbS CQD‐based optoelectronic devices are also provided.