Oriented layered Bi_2O_2Se nanowire arrays for ultrasensitive photodetectors

摘要

Due to its high carrier mobility, superior air stability, and intriguing self-modulation doping effects, Bi2O2Se has shown great potential for applications in high performance field-effect transistors and infrared photodetectors. However, Bi2O2Se generally tends to form 2D micromorphology because of its native layered structure. Here, we developed a space-confined CVD method to realize the epitaxial growth of highly oriented 1D Bi2O2Se arrays. The controllable length and width of the vertical growth nanowires mainly distribute in the ranges of 30-42 mu m and 120-160 nm, respectively. The orientation of Bi2O2Se nanowires was determined by the epitaxial relationship between Bi2O2Se {110} and mica {00n} planes. In addition, various morphologies of Bi2O2Se including 1D nanowires, 2D nanosheets, and rectangular nanosheets can be controllably synthesized by precisely modifying the growth temperature. The integrated detector based on the as-synthesized Bi2O2Se nanowire arrays demonstrated excellent performances in the spectrum from the UV to near-infrared regime. The responsivity, detectivity, external quantum efficiency, and response time can reach up to 722.2 A W-1, 5.64 x 10(11) Jones, 189 000%, and 0.267 ms, respectively. These findings manifest that the oriented Bi2O2Se nanowire arrays have great prospects in ultrafast and near-infrared photodetection applications. Published under license by AIP Publishing.