Although germanium-and silicon-based detectors have been commercialized for NIR photodetection, [4,5] their response speeds and sensitivities still have potential for improvement. It has also been reported that 2D materials have great potential for application in low-cost, room temperature, and large-area visible-near-infrared (VIS-NIR) photodetection applications owing to their excellent optical and electronic properties, [6][7][8][9][10][11][12] and various VIS-NIR photodetectors based on 2D materials have been reported. For example, graphene has been demonstrated to exhibit a rapid photoresponse; however, its lack of a bandgap, low light absorption properties, and low intrinsic sensitivity hinder its potential applications in VIS-NIR detection. [13,14] As alternatives, transition metal dichalcogenides (TMDs) exhibit large bandgaps for infrared detection, [15,16] and black phosphorus (BP) exhibits a good performance in infrared photodetection owing to its suitable bandgap and fast carrier mobility; [17,18] however, the latter suffers from a poor air stability. Furthermore, despite the fact that heterostructure photodetectors have been shown to exhibit high performances, they require complex transfer processing. [19][20][21] Considering the above systems, it is therefore apparent that the development of suitable VIS-NIR-responsive materials would be highly attractive.In this context, Bi 2 O 2 Se has recently attracted increasing attention because of its suitable electronic bandgap (≈0.8 eV), high carrier mobility (≈450 cm 2 V −1 s −1 at 300 K), excellent air stability, high conductivity, and environmental non-toxicity, which render it an ideal candidate for VIS-NIR detection. [22][23][24][25][26][27][28] However, its high carrier concentration leads to a large dark current in detectors based on Bi 2 O 2 Se nanosheets, which restricts any further performance improvement being achieved. To address this issue, previous studies have examined the use of gate voltage regulation [29,30] and heterostructure construction. [31][32][33] However, the application of extremely high gate voltages increases the power consumption of the device, and the construction of heterostructures often requires complex transfer processes. In addition, the reported Bi 2 O 2 Se photodetectors tend to show poor response speeds in the NIR waveband (i.e., tens of milliseconds), which limits their application in high-speed detection. [27,34] 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 m...