A near-infrared organic photodetector based on an aza-BODIPY dye for a laser microphone system

Abstract

Near-infrared (NIR) photodetectors play an irreplaceable role in many fields, such as aerospace, astronomy, meteorology, military, civil, and industry. Among them, NIR organic photodetectors (OPDs) have attracted widespread attention due to their variable structure and simple low-cost processing but are limited by the low detection sensitivity originating from the early absorption cut-off and weak absorption in the NIR region. Herein, we designed and synthesized a novel NIR-sensitive aza-BODIPY dye (BODIPY-F) with a narrow bandgap for solution-processed NIR-OPDs, showing a remarkable performance with an external quantum efficiency (EQE) of 18.15% at 840 nm and a specific detectivity (D*) up to 10¹¹ Jones in the NIR range (780–930 nm). In addition, the OPDs exhibit a fast response time of 0.5 μs and a bandwidth of 700 kHz. Benefiting from the excellent device performance, the fabricated NIR-OPD is integrated into the laser microphone system as an optical signal receiver, effectively devoted as both NIR laser alarm and low-frequency communication with low delay and high fidelity. Our work innovatively utilizes the high-performance NIR-OPD based on BODIPY-F in the laser microphone system, which is expected to promote the wide application of OPDs.