BiI_(3)修饰Cs_(3)Bi_(2)I_(9)自供能光电化学型探测器制备及其性能

Fabrication and Performance of Self-powered Photoelectrochemical Detectors Based on BiI_(3) Modified Cs_(3)Bi_(2)I_(9)

在溶液法合成Cs_(3)Bi_(2)I_(9)前驱体溶液的基础上,采用添加BiI_(3)修饰Cs_(3)Bi_(2)I_(9)溶液的方法后得到Cs_(3)Bi_(2)I_(9)/BiI_(3)薄膜并制备出具有自供能特性的Cs3Bi2I9/BiI3薄膜光电化学型探测器。结果表明,添加的BiI3以第二相形式存在于Cs_(3)Bi_(2)I_(9)薄膜中,形成两相混合结构。在紫外光(365 nm)单色光照射下,Cs_(3)Bi_(2)I_(9)/BiI_(3)探测器的开关比达到3198,响应度和探测率分别为2.85×10^(-3) A/W和3.77×10^(10) Jones。在绿光(530 nm)单色光照射下,Cs_(3)Bi_(2)I_(9)/BiI_(3)探测器的开关比达到1172,响应度和探测率分别为6.9×10^(-4) A/W和1.76×10^(10) Jones,同时展现出红光波段(625 nm)的良好响应。相较于Cs_(3)Bi_(2)I_(9)探测器,Cs_(3)Bi_(2)I_(9)/BiI_(3)器件探测性能均有大幅度提高,归因于BiI_(3)对非辐射缺陷的钝化作用。本工作首次尝试将Cs3Bi2I9应用在光电化学型结构探测器中,通过BiI3的修饰成功提高了器件性能,为低毒铋基钙钛矿的光电探测应用性能提升提供了新思路。

Based on the synthesis of Cs_(3)Bi_(2)I_(9) precursor solution by using solution method,Cs3Bi2I9/BiI3 thin films were obtained by adding BiI_(3) to modify Cs3Bi2I9 solution,and the Cs_(3)Bi_(2)I_(9)/BiI_(3) photodetectors based on the device types of photoelectrochemical detectors with self-powered properties were also constructed.It is found that the added BiI3 exists in the form of the second phase,forming a two-phase mixed structure.Under illumination of ultraviolet(365 nm)monochromatic light,Cs3Bi2I9/BiI3 photodetectors show on-off ratio of 3198,corresponding to a response of 2.85×10^(-3) A/W and a detectivity of 3.77×10^(10) Jones.While under illumination of green light(530 nm),the device also exhibits on-off ratio of 1172,a response of 6.9×10^(-4) A/W and a detectivity of 1.76×10^(10) Jones.Compared with simple Cs_(3)Bi_(2)I_(9) photodetectors,the detection performance of Cs_(3)Bi_(2)I_(9)/BiI^(3) photodetectors has been greatly improved,which is attributed to the passivation of BiI_(3) on non-radiation defects.It is the first time to apply Cs_(3)Bi_(2)I_(9) in the photoelectrochemical structure detector.The modification of BiI_(3) successfully improves the device performance,which provides a new idea for improving the performance of low-toxic bismuth-based perovskite photodetection application.