Ultrasensitive UV-NIR broadband phototransistors based on AgBiS2–organic hybrid films

Abstract

In recent years, AgBiS₂ has received great attention in optoelectronics thanks to its fascinating merits, including a suitable bandgap, large absorption coefficient from ultraviolet to near-infrared and remarkable material stability. However, the poor carrier transport properties limit its further development and applications. To address this issue, we propose a composite strategy to facilitate the carrier transport of AgBiS₂ QD films. The AgBiS₂–organic hybrid films demonstrated enhanced photoconductivity. Then, we fabricated phototransistors based on these blend films, and achieved a high photosensitivity (I_light/I_dark) of 1.5 × 10³, a decent responsivity of up to 20 A W⁻¹, an excellent specific detectivity of 4 × 10¹³ Jones under low UV illumination and remarkable device stability. These results again demonstrate the great potential of AgBiS₂ for next generation solution-processed photodetectors.