Quantum‐Dot Intermediate Band Semiconductors: From Materials to Applications

Solar cells fabricated with intermediate band (IB) materials demonstrate remarkable potential to achieve up to 63% efficiency under maximum solar concentration, while enabling broad‐spectrum photodetectors and high‐efficiency LEDs through superior carrier injection and light emission. The unique electronic configuration of quantum‐dot intermediate band semiconductors (QD‐IBS) where quantum‐confined potential wells create a partially filled IB within the host semiconductor's bandgap ‐ facilitates sub‐bandgap photon absorption/emission for enhanced solar spectrum utilization and manipulation. This breakthrough mechanism establishes QD‐IBS materials as transformative platforms for next‐generation green energy and health‐conscious lighting technologies. This comprehensive review systematically examines recent advancements in QD‐IBS materials through three key perspectives: 1) Innovative synthesis methodologies addressing quantum dot uniformity and IB engineering challenges; 2) Strategic optimization approaches comparing strain engineering, surface passivation, and band alignment modulation techniques; 3) Cutting‐edge applications spanning high‐efficiency photovoltaics, broadband photodetection, and wavelength‐tunable LEDs. By conducting critical analysis of structure‐property relationships and performance limitations, this work identifies fundamental gaps between theoretical predictions and experimental realizations. The work further proposes novel research directions focusing on defect suppression in IB formation and multi‐exciton generation mechanisms, providing valuable insights for overcoming existing bottlenecks in practical device implementation.