High‐Performance Visible to Near‐Infrared Broadband Bi 2 O 2 Se Nanoribbon Photodetectors

Owing to its suitable electronic bandgap, excellent air stability, and high carrier mobility at room temperature, low‐dimensional bismuth oxyselenide (Bi 2 O 2 Se) has become attractive in the context of visible–near‐infrared (VIS–NIR) detection. However, the high carrier concentration and bolometric effect of Bi 2 O 2 Se nanosheets are not conducive to reducing the dark current and improving the response speed, which hinders Bi 2 O 2 Se nanosheet‐based photodetectors from achieving an optimal performance. In this study, a Bi 2 O 2 Se nanoribbon is controllably synthesized on a fluorophlogopite substrate by means of the chemical vapor deposition approach. Through the use of a Bi 2 O 2 Se nanoribbon structure and the application of a Schottky barrier between the Bi 2 O 2 Se and Au electrodes, a fast response and low noise photodetector is achieved. More specifically, the response times are 2.1 and 313 µs at 650 and 1550 nm, respectively, and the corresponding optimal detectivities are 3.28 × 10 13 and 8.07 × 10 9 Jones. Furthermore, the device reaches a −3 dB bandwidth of 81 kHz and exhibits a responsivity of 3.2 × 10 5 A W −1 at 650 nm under a bias of 5 V. This study provides new opportunities for the application of high‐performance VIS–NIR photodetectors.