Room-Temperature High-Detectivity Flexible Near-Infrared Photodetectors with Chalcogenide Silver Telluride Nanoparticles

Herein, flexible near-infrared (NIR) photodetectors were prepared using silver telluride (Ag₅Te₃) nanoparticles (NPs) for optoelectronic applications. For the main channel materials of the photodetectors, Ag₅Te₃NPs were used, which were synthesized in an aqueous solution. Moreover, Ag₅Te₃thin films were successfully fabricated on plastic substrates at 150 °C using redistributed Ag₅Te₃NPs in aqueous inks. The crystal structure, chemistry, and optoelectronic properties of the synthesized photodetectors were studied. The fabricated flexible Ag₅Te₃-based photodetectors achieved a detectivity of 6.27 × 10⁹cm Hz^1/2W^-1(>10⁹) at room temperature under 0.35% compressive and tensile strains. The obtained detectivity value exceeds those of two-dimensional inorganic layered material phototransistors such as MoS₂or commercial thermistor bolometers at room temperature (10⁹). Furthermore, the proposed novel method for the synthesis of Ag₅Te₃thin films on plastic substrates can be applied to other Ag₅Te₃-based applications in the future.