High-Resolution Radiation Sensors from Flexible Network Nanocomposites of Nanoparticles and Aramid Nanofibers.

Abstract

Rapid, sensitive, and continuous radiation detection for personnel and critical electronic equipment is essential in nuclear, medical, space, and other advanced technologies. Achieving this requires materials that combine a high cross-section for capturing high-energy photons, efficient charge carrier generation, and high conductivity while also being solution-processable, mechanically flexible, and durable for scalable, lightweight devices. Here, we demonstrate that nanostructured semiconductor composites composed of aramid nanofibers (ANFs) and CdTe nanoparticles (NPs) can meet these often-contradictory demands. These solution-processable materials exhibit high conductivity and charge collection efficiency, enabled by the self-assembly of NPs into continuous interdigitated charge-transporting pathways. Notably, the nanostructured medium enhances the photon-to-current transduction efficiency beyond that of a homogeneous material with equivalent composition and stopping power. Radiation detectors fabricated from CdTe/ANF composites achieve energy resolution for X- and γ-ray detection comparable to that of state-of-the-art high-purity germanium detectors while operating at room temperature. Furthermore, the biomimetic cartilage-like architecture of the tough ANF matrix ensures no loss of performance after 1000 bending cycles. This combination of hard-to-obtain properties makes CdTe/ANF nanocomposites promising candidates for next-generation, high-performance radiation shielding.