Shang Huiming, Chen Hongyu, Dai Mingjin, Hu Yunxia, Gao Feng, Yang Huihui, Xu Bo, Zhang Shichao, Tan Biying, Zhang Xin, Hu PingAn
School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150080, China and Key Laboratory of Micro-systems and Micro-structures Manufacturing of Ministry of Education, Harbin Institute of Technology, Harbin 150080, China.
Key Laboratory of Micro-systems and Micro-structures Manufacturing of Ministry of Education, Harbin Institute of Technology, Harbin 150080, China.
Nanoscale Horiz. 2020 Mar 2;5(3):564-572. doi: 10.1039/c9nh00705a.
Mixed-dimension van der Waals (vdW) p-n heterojunction photodiodes have inspired worldwide efforts to combine the excellent properties of 2D materials and traditional semiconductors without consideration of lattice mismatch. However, owing to the scarcity of intrinsic p-type semiconductors and insufficient optical absorption of the few layer 2D materials, a high performance photovoltaic device based on a vdW heterojunction is still lacking. Here, a novel mixed-dimension vdW heterojunction consisting of 1D p-type Se nanotubes and a 2D flexible n-type InSe nanosheet is proposed by a facile method, and the device shows excellent photovoltaic characteristics. Due to the superior properties of the hybrid p-n junction, the mix-dimensional van der Waals heterojunction exhibited high on/off ratios (103) at a relatively weak light intensity of 3 mW cm-2. And a broadband self-powered photodetector ranging from the UV to visible region is achieved. The highest responsivity of the device could reach up to 110 mA W-1 without an external energy supply. This value is comparable to that of the pristine Se device at 5 V and InSe device at 0.1 V, respectively. Furthermore, the response speed is enhanced by one order of magnitude over the single Se or InSe device even at a bias voltage. This work paves a new way for the further development of high performance, low cost, and energy-efficient photodetectors by using mixed-dimensional vdW heterostructures.
混合维度范德华（vdW）p-n异质结光电二极管激发了全球范围内的研究热情，致力于在不考虑晶格失配的情况下，将二维材料和传统半导体的优异特性结合起来。然而，由于本征p型半导体的稀缺以及少数层二维材料光吸收不足，基于范德华异质结的高性能光伏器件仍然匮乏。在此，通过一种简便方法提出了一种由一维p型硒纳米管和二维柔性n型硒化铟纳米片组成的新型混合维度范德华异质结，该器件展现出优异的光伏特性。由于混合p-n结的卓越性能，混合维度范德华异质结在3 mW cm-2的相对较弱光强下呈现出高达103的开/关比。并且实现了一种从紫外到可见光区域的宽带自供电光电探测器。在无外部能量供应的情况下，该器件的最高响应度可达110 mA W-1。该值分别与在5 V偏压下的原始硒器件以及在0.1 V偏压下的硒化铟器件相当。此外，即使在偏压下，其响应速度也比单一的硒或硒化铟器件提高了一个数量级。这项工作为利用混合维度范德华异质结构进一步开发高性能、低成本且节能的光电探测器开辟了一条新途径。
