钙钛矿/高分子复合物光电探测器构筑及其功能特性研究

Photodetectors are transducers that convert photons directly to electrical signal, which underpins modern science and technology. Currently, most of the commercial photodetectors are based on inorganic semiconductors, e.g., silicon, germanium and gallium arsenide, which require high temperature and high vacuum processing techniques and result high cost. In the last few years, organic-inorganic hybrid perovskites have emerged as one of the most promising materials for solution-processed photodetectors, benefiting from their excellent opto-electronic properties. Despite of the rapid progress and the realization of high-performance perovskite photodetectors, there are still a few issues need to be addressed towards manufacturing and commercialization, including long-term stability, miniaturization and integration, and further enhancement of the device performance. This proposal aims to solve these problems and develop novel perovskite photodetectors based on high quality perovskite/polymer composites. The opto-electronic properties of these novel perovskite composites will be systematically characterized via advanced techniques, e.g., transient photovoltage/photocurrent and time-resolved spectroscopy. The morphology, stability, dimensionality, ion migration and degradation mechanism of the materials and devices will be fully investigated. The device performance of these optimized perovskite photodetectors will be further enhanced, leading to the bright avenue of next generation photodetecton.

光电探测器是能把光直接转化为电信号的元器件，在多个领域都有广泛应用。但目前主流的商业化光电探测器都是基于硅、锗、砷化镓等无机半导体材料。而这些材料一般都需要高温、高真空制备，成本较高。近年来，有机-无机杂化钙钛矿由于其具有优异的光电性能和可低成本溶液加工或低真空、低温蒸镀制备的特点，已在光电探测器应用方面获得了迅猛的发展。尽管钙钛矿探测器已经实现良好的器件性能，但与商业化应用的要求还有一定距离，主要体现在材料和器件稳定性欠佳，元器件还未真正实现小型化和集成，以及器件性能还需要进一步提高。本申请正是基于上述问题，为了达到上述目标提出的。主要以新型、高稳定性钙钛矿/高分子复合薄膜和纳米纤维的制备、生长为基础，围绕材料形貌控制、稳定性、多维度调控、光电转化机理、离子迁移和蜕变机制这些关键科学问题和技术难题，以实现高性能、高稳定性的钙钛矿光电探测器为目的，为下一代光电探测和成像提供重要技术支持。

自钙钛矿材料被报道以来，近几年迅速发展成为一种新型的光电材料。然而其稳定性问题一直是制约其发展的重要因素。本项目致力于获得高性能、高稳定性的新型钙钛矿光电探测器，以材料的性能表征和器件的制备为基础，通过探索大颗粒钙钛矿单晶生长、钙钛矿/高分子复合纳米纤维工艺，来揭示钙钛矿/高分子复合材料中晶体、薄膜、纤维的生长调控机制，研究了新型钙钛矿复合材料在光电转换过程中的新特性与新机制。取得的研究成果主要概括如下：1. 结合前期的工作，对新型钙钛矿材料进行了深层次的研发及表征，制备出了高性能的类卤素、铷掺杂FAPbI3和二维/三维复合钙钛矿材料并制备了性能优异的光电探测器；2. 针对钙钛矿材料对水敏感性问题，我们通过将钙钛矿材料与疏水的高分子材料复合，制备出了高稳定性的钙钛矿/高分子复合材料及器件；3. 采用静电纺丝法快速大量地制备出不同形貌、尺寸的复合纳米纤维及器件。这些取得的研究成果和积累的研究经验，对新型钙钛矿复合材料的制备及其在光电领域的应用都具有重要的指导意义，为下一代高性能光电探测提供了重要的技术支持。