基于异质结界面电荷分离的高响应紫外光探测器件制备及性能研究

Ultraviolet (UV) photodetector (PD) is a kind of dual-purpose use of military facilities which has important applications in military affairs, medicine, environment and fire sensing. Organic ultraviolet detector (OUV-PD) based on heterojunction interface dissociation has been a new active research field in recent years. Compared to UV-PD based on inorganic materials, OUV-PD exhibits many advantages such as abundant resource, ease fabrication, low cost and large area, and so on. The aim of this project is to utilize low cost ITO glass substrates, organic small molecular materials, physical vapour deposition technique and heterojunction device structure to design and fabricate OUV-PDs which possess high photocurrent response and excellent stability. We will select novel organic small molecular materials and Cu(I) complexes as acceptors to fabricate OUV-PD by using heterojuction device structure. And also we will explore the relationship between the chemical structures, photophysical and electrochemical properties, charge transport abilities, thermal stabilities and film morphology of materials and the performance of OUV-PD by using advanced characterizing techniques. In addition, we will introduce the buffer layer into OUV-PD to enhance the device stability. Our investigation will provide theoretical evidence and experimental base for practical applications of OUV-PD.

紫外光探测器在军事、医药、环境及火灾监测等领域有着重要的应用，是一类军民两用型器件。基于异质结界面电荷分离的有机紫外光探测器是近几年发展起来的一个新兴热门研究领域。与无机紫外探测器相比，具有材料来源广、工艺简单、成本低及可制备成大面积器件等优点。本课题集中导电玻璃衬底、有机小分子材料、物理气相沉积技术和异质结型器件结构的优点，设计并制备高电流响应且稳定性好有机紫外光探测器件。选择具有较高电子迁移率的有机小分子和铜配合物新材料作为受体，采用异质结型器件结构制备紫外光探测器件；运用先进的表征手段，阐述材料分子结构、光物理和电化学性质、载流子传输能力、薄膜形貌、热稳定性与器件紫外光探测性能之间的构效关系；将有机薄膜器件中的缓冲层引入到紫外光探测器件中，提高器件的使用寿命。本项目的研究将为有机紫外光探测器件的实际应用提供理论依据和实验基础。

本项目主要是利用多氮杂环配体构筑了一系列Cu(I)配合物三线态材料，利用元素分析、X-射线单晶衍射对其结构进行了表征。筛选出与Cu(I)配合物能级相匹配的功能材料，采用真空镀膜技术制备了基于Cu(I)配合物的有机紫外光探测器件，系统的研究了配合物的化学结构、器件结构与光伏性能的构效关系。筛选功能层材料并引入阴阳极缓冲层制备了有机紫外光探测器件，研究了器件性能与结构之间的关系。.历经三年的深入研究，该项目取得了原创性的研究成果，尤其是研发出的价廉、环保的系列单核Cu(I)配合物三线态材料，在有机光电领域的应用研究取得突破性的进展。其中基于[Cu(BDphos)(BCP)]BF4 (CuBB)为电子受体的有机紫外光探测器件，在0.691 mW/cm2的365 nm波长紫外光照射下，电压在-10 V时它的响应度达到了251 mA/W，电流密度为173 μA/cm2。基于[Cu(DPEphos)(PyPhen)]BF4(CuDP)和[Cu(BDphos)(PyPhen)]BF4(CuBP)的有机紫外光探测器件，在1.75 mW/cm2的365 nm波长紫外光照射下，电压在-12 V时它们的响应值分别达到了140和276 mA/W。引入HATCN为阳极缓冲层，器件最大响应值达到508 mA/W，寿命达到500 min；引入Bphen、Zn(4-MeBTZ)2、TPBi和Liq为阴极缓冲层，响应度均获得提高。.相关研究成果发表SCI收录论文4篇，EI收录论文2篇。申报国家发明专利4项，授权3项。该项目的研究大大拓展了有机光电材料的选择范围，为Cu(I)配合物三线态材料在有机紫外光探测领域的实际应用提供了理论和实践基础。