LAUSR

Two-dimensional (2D) materials have recently received great attention for their atomic thin thickness and thus derived outstanding electrical, optical and optoelectronic properties. Moreover, the dangling-bond-free surfaces of 2D materials enable the direct integration of different materials with various properties through van der Waals (vdW) forces into vdW heterostructures, providing new opportunities for constructing new type devices with superior performances. In this study, we report the vertical assembly of n-type CdS and p-type BP into p-n junctions. The electrically tunable heterojunction device shows a high current rectifying ratio up to 8×10 3 at a low bias voltage range of ±1 V and an ideality factor of 1.5. More interestingly, the CdS/BP vdW heterojunction exhibits an ultra-high photoresponsivity up to 9.2×10 5 A W −1 and an ultra-high specific detectivity of 3.2×10 13 Jones with a low bias voltage of 1.0 V, which is among the highest in the reported results of 2D heterostructures. While operated at a self-powered mode, the device also exhibits excellent photodetection performances with a high photoresponsivity of 0.27 A W −1 and a high external quantum efficiency of 76%. Time-resolved photoresponse characterizations indicate that the device possesses a fast response time of about 10 ms. The developed CdS/BP vdW heterojunctions will find potential applications in the next-generation nanoscale electronics and optoelectronics applications. 近年来二维材料因其超薄的厚度及新颖的电、光及光电特 性受到了广泛关注. 此外, 二维材料表面无悬挂键, 这使得其可以直 接通过范德华力相互结合形成范德华异质结, 为构建具有优异性 能的新型器件提供了新的机遇. 本文采用范德华集成方法将n型硫 化镉和p型黑磷垂直堆垛起来构筑了p-n结二极管. 输运特性测试 表明, 该p-n结器件表现出高的整流比(8×10 3 )和低的理想因子(1.5). 同时, 在光照下器件表现出超高的光响应度和比探测率, 分别可达 9.2×10 5 A W −1 和3.2×10 13 Jones, 与目前所报道的二维异质结光电 探测的最高水平相当. 当器件工作于自驱动探测模式时, 仍表现出 极好的光探测性能, 光响应度和响应速度分别可达0.27 A W −1 和 ~10 ms. 所制备的硫化镉/黑磷异质结器件将会在新一代纳米电 子、光电子器件中扮演重要角色.