Two-dimensional (2D) ternary wide-bandgap semiconducting materials have great potential in power device, flexible electronic device, short-wavelength light emitting diodes (LEDs) and photodetectors due to the controllable bandgap, strong light-material interaction, and controlled freedom degree of stoichiometry variation. However, it is still a great challenge to precisely control the growth of high-quality 2D ternary wide-bandgap semiconducting materials due to the variety of components, which hinders their development for practical applications. In this work, high-quality 2D ternary bismuth oxybromide single-crystal nanosheets with a high yield were prepared by space-confined chemical vapor deposition (CVD) method. The devices based on 2D ultrathin BiOBr single-crystal nanoflakes show a high UV detecting performance including low dark current (I_dark) of 1.46 pA and high responsivity (R), external quantum efficiency (EQE) and detectivity (D*) of 14.96 A W⁻¹, 5460%, and 5.74 × 10¹⁰ Jones, respectively, as well as fast response process (τ_rise =80 ms, τ_decay =40 ms). The excellent UV performance can be ascribed to the photogating effect by trapped states, which endow it with great potential for high-performance UV detectors.

二维（2D）三元宽带隙半导体材料由于带隙可控，光材料相互作用强，自由度可控而在功率器件，柔性电子器件，短波长发光二极管（LED）和光电探测器中具有巨大潜力化学计量变化。但是，由于组件的多样性，精确控制高质量2D三元宽带隙半导体材料的增长仍然是一个巨大的挑战，这阻碍了它们在实际应用中的发展。在这项工作中，通过空间限制化学气相沉积（CVD）方法制备了高产率的高品质二维二维三溴化铋铋单晶纳米片。基于2D超薄BiOBr单晶纳米薄片的器件显示出高紫外线检测性能，包括低暗电流（我_暗1.46帕）和高响应（[R ），外量子效率（EQE）和探测（d 14.96 AW *）^-1，5460％，和5.74×10 ¹⁰琼斯，分别，以及快速的响应处理（τ_上升= 80毫秒，τ_衰减= 40毫秒）。出色的紫外线性能可以归因于捕获态的光闸效应，这为其高性能的紫外线检测器提供了巨大的潜力。