二维金属卤化物钙钛矿/过渡金属硫族化合物异质结构的可控制备及光电特性研究

Atomically thin two-dimensional (2D) materials and their heterostructures have shown many novel and unique optoelectronic properties due to quantum confinement effect. The emerging 2D materials have shown promising application potentials in the next-generation optoelectronic devices, green electronics and flexible electronics. However, conventional 2D materials, such as MoS2, WS2 and et al., commonly limited by their atomically thin layer thickness, exhibit poor photon absorption capability and limited photo responsibility. In this proposal, we plan to synthesize 2D organic-inorganic perovskites (HOIPs)/2D transitional metal dichalcogenide (TMDCs) heterostructures via van der Waals epitaxial growth method. The band structures of these 2D materials can be further tuned by defect engineering, composition modification, chemical doping and et al., which will result in desired band alignment to optimize device performance. Based on this research, a contact model of atomically thin 2D materials will be established. We are aiming at building up novel 2D optoelectronic devices with high photo responsibility, high charge mobility, wide wavelength, and with tuneable band gap, which paves the way for practical applications of 2D materials in the field of high performance, and highly integrated photodetection.

原子级超薄二维半导体材料及其异质结构因量子局域效应展现出诸多优异的光电特性，在新型光电器件、低能耗器件、柔性电子电路等方面具有极大的应用前景。申请人针对传统共价型单层二维半导体材料（如二硫化钼、二硫化钨等）光捕获能力不足、光响应度低等问题，拟在前期工作基础上，通过外延生长法以共价型二维层状半导体材料为基底，制备离子型二维有机-无机杂化钙钛矿纳米片，从而形成超薄二维异质结构。利用二维材料缺陷工程、成分配比调控、化学掺杂等方法，进一步优化材料能级结构，并最终构建原子级厚度的二维材料异质结构接触模型。以此为基础，构建出具有高光电响应系数、高载流子迁移率、宽波段、带隙可调等优良特性的新型超薄二维异质结构光电器件，为二维纳米材料在高性能、高集成化光电探测领域的应用铺平道路。

原子级超薄二维半导体材料及其异质结构具有诸多优异的光电特性，在新型光电器件、低能耗器件、柔性电子电路等方面具有极大的应用前景。然而传统共价型单层二维半导体材料（如二硫化钼、二硫化钨等）其材料厚度仅有原子级，光在材料中有限的传播距离使得低维单层半导体材料对光的捕获能力不足，其光电探测器存在光响应度低等诸多问题。本课题通过外延生长法利用具有晶格适配的材料生长基底，制备离子型二维有机-无机杂化钙钛矿纳米片，进而与二维单层过渡金属硫族化合物半导体材料形成超薄二维异质结构。利用二维材料缺陷工程、成分配比调控、化学掺杂等方法，进一步优化材料能级结构，通过光电测试，荧光寿命量测，以及扫描光电流成像等测试手段，揭示二维异质结构光电器件作用机制，最终构建原子级厚度的二维材料异质结构接触模型。通过本项目的实施可有效提升低维材料光电器件光电响应系数、拓展光响应波段，获得新型超薄二维异质结构光电器件，为二维纳米材料在高性能、高集成化光电探测领域的应用铺平道路。