CsPbI₃ Nanotube Photodetectors with High Detectivity

In the present work, the exploration of photodetectors (PDs) based on CsPbI₃ nanotubes are reported. The as-prepared CsPbI₃ nanotubes can be stable for more than 2 months under air conditions. It is found that, in comparison to the nanowires, nanobelts, and nanosheets, the nanotubes can be advantageous to be used as the functional units for PDs, which is mainly attributed to the enhanced light absorption ability induced by the light trapping effect within the tube cavity. As a proof of concept, the as-constructed PDs based on CsPbI₃ nanotube present an overall excellent performance with a responsivity (R_λ ), external quantum efficiency (EQE) and detectivity of 1.84 × 10³ A W^-1 , 5.65 × 10⁵ % and 9.99 × 10¹³ Jones, respectively, which are all comparable to state-of-the-art ones for all-inorganic perovskite PDs.