Zhou Xuefei, Tian Ziao, Kim Hyuk Jin, Wang Yang, Xu Borui, Pan Ruobing, Chang Young Jun, Di Zengfeng, Zhou Peng, Mei Yongfeng
Department of Materials Science and State Key Laboratory of ASIC and system, Fudan University, Shanghai, 200433, P. R. China.
State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, 200050, P. R. China.
Small. 2019 Oct;15(42):e1902528. doi: 10.1002/smll.201902528. Epub 2019 Sep 4.
Transition metal dichalcogenides, as a kind of 2D material, are suitable for near-infrared to visible photodetection owing to the bandgaps ranging from 1.0 to 2.0 eV. However, limited light absorption restricts photoresponsivity due to the ultrathin thickness of 2D materials. 3D tubular structures offer a solution to solve the problem because of the light trapping effect which can enhance optical absorption. In this work, thanks to mechanical flexibility of 2D materials, self-rolled-up technology is applied to build up a 3D tubular structure and a tubular photodetector is realized based on the rolled-up molybdenum diselenide microtube. The tubular device is shown to present one order higher photosensitivity compared with planar counterparts. Enhanced optical absorption arising from the multiple reflections inside the tube is the main reason for the increased photocurrent. This tubular device offers a new design for increasing the efficiency of transition metal dichalcogenide-based photodetection and could hold great potential in the field of 3D optoelectronics.
过渡金属二硫属化物作为一种二维材料，由于其带隙在1.0到2.0电子伏特之间，适用于近红外到可见光的光电探测。然而，由于二维材料的超薄厚度，有限的光吸收限制了光响应性。三维管状结构由于具有光捕获效应，可以增强光吸收，从而为解决该问题提供了一种解决方案。在这项工作中，得益于二维材料的机械柔韧性，采用自卷技术构建了三维管状结构，并基于卷绕的二硒化钼微管实现了管状光电探测器。与平面同类器件相比，该管状器件的光敏性提高了一个数量级。管内多次反射引起的光吸收增强是光电流增加的主要原因。这种管状器件为提高基于过渡金属二硫属化物的光电探测效率提供了一种新的设计，在三维光电子学领域具有巨大潜力。
