Decorating Perovskite Quantum Dots in TiO2 Nanotubes Array for Broadband Response Photodetector

Abstract Broadband photodetectors based on TiO 2 nanotubes (NTs) array have significant prospects in many fields such as environmental monitoring. Herein, a simple spin‐coating process is successfully adopted to incorporate MAPbI 3 quantum dots (QDs) onto the surface of TiO 2 NTs to form a heterostructure, extending the response range of TiO 2 NT from ultraviolet to visible. Compared with pure TiO 2 NTs, the heterostructure demonstrates an improvement of responsivity in visible range by three orders of magnitude, and maintains its response performance in the UV range simultaneously. The TiO 2 NTs based heterostructure photodetectors demonstrate a relative fast and stable response in the 300–800 nm range and even have a reponsivity of 0.2 A W −1 at 700 nm. The photoelectric performance of the hybrid photodetector based on TiO 2 NTs maintains well when exposed to moist air for 72 h or heated from room temperature to 100 °C. Moreover, such a TiO 2 NTs/MAPbI 3 QDs heterostructure device demonstrates excellent flexibility and high transparency (85%) in the 400–800 nm range, their photodetecting performance is well retained after 200 cycles of repeated bending at 90°. The present strategy that combines facile electrospinning and solution‐processed QDs may open a new avenue for wide range response and flexible devices construction.