High-performance bifunctional near-infrared diode enabled by intentional manipulation of energy transfer and carrier injection with a hetero-active-layer†

Abstract

The realization of integrating the generation and reception of optical signals into a single device in the near-infrared (NIR) region is of great value for biometric applications. However, existing semiconductors have limitations in material synthesis and device fabrication, which prevent the fabrication of high-performance integrated devices at low cost. Here, we proposed a bifunctional near-infrared hetero-diode based on FAPbI₃/CdSe QDs. The QDs exhibited efficient Förster resonance energy transfer (FRET) to the perovskite, while the hole injection barrier, due to the deeper valence band of the QDs, regulated the number of injected holes, resulting in more balanced carrier injection. The hetero-diode improved its EQE from 16.9% to 21.6% as an emitter compared to the FAPbI₃ diode and achieved an improved on/off ratio from 2 × 10² to 3 × 10³ as a sensing unit. This study opens up a new approach to improving the performance of bifunctional devices.