Review of 2D Bi 2 X 3 (X = S, Se, Te): from preparation to photodetector

Abstract Detector has become an indispensable part of human beings. The increasing demand for photodetectors with high performance has promoted the research of novel materials. At the same time, with the development of rising material system, two‐dimensional (2D) materials attract a lot of attention, while the suitable option for fabricating photodetector is still limited. The prospering of bismuth chalcogenides injected new vitality for material field, thereinto, the unique topological insulator characteristics make the research on bismuth selenide (Bi 2 Se 3 ) and bismuth telluride (Bi 2 Te 3 ) intriguing. 2D Bi 2 X 3 also exhibits unique features among various 2D materials, of which, the adjustable narrow energy band gap and polarization‐sensitive photocurrent contribute to the promising application of high performance and broadband photodetector. In this review, from a bottom‐up perspective, we summarize fundamental properties, synthesis method, photodetector performance of 2D Bi 2 X 3 based on the previous study, which provide an overall perspective of 2D Bi 2 X 3 . Wherein, the section of the photodetector is specifically discussed with regard to pure Bi 2 X 3 photodetector and heterojunction photodetector. A brief summary and outlook were also explored in the end.