Exploring the Potential of Colloidal Quantum Dots for Near‐Infrared to Short‐Wavelength Infrared Applications

Colloidal quantum dots (CQDs) are powerful components for next‐generation infrared (IR) optoelectronic devices owing to their confinement‐based bandgap‐tunability, cost‐efficiency, and solution‐processability. The strong absorption feature of CQDs from the near‐infrared to short‐wavelength infrared renders them ideal as absorbers in both photovoltaics (PVs) and photodetectors (PDs). To effectively integrate CQDs into these devices, a better understanding of their film properties and a refined approach to material and device architecture are essential. Additionally, compliance with environmental standards for the material design presents a challenge for their widespread application. Therefore, the essential characteristics of CQD films to design optimal IR harvesting optoelectronics are highlighted, for instance, the spectral range, doping polarity/concentration, and energy levels. Subsequently, recent advancements in CQD‐based tandem PVs are explored, covering the key considerations in the fabrication of two‐terminal devices and strategies for enhancing the power‐conversion‐efficiency of large‐sized CQD‐based PVs. The study then explored a CQD‐based photodetector, highlighting the approaches for reducing the dark current and improving the external‐quantum‐efficiency, and the recent progress in Pb‐free CQD PDs is discussed. Finally, the perspectives regarding the current challenges and future directions that are critical for advancing the field of PV and PD are presented.