Low Temperature Photochemical Sol-Gel Processing of Functional Thin Films and their Applications

该项目旨在开发在低温溶液加工中精确控制功能无机薄膜的通用方法，以实现柔性电子产品的卷对卷制造。今年，发现溶液处理的非晶金属有机薄膜锌（II）甲氧基乙氧基氧化物（ZME）在倒置有机发光二极管（iOLEDs）中作为一种高效稳定的电子注入层（EIL）。相比之下，利用真空紫外线（VUV）光照射或高温退火获得的ZnO结晶会导致强烈的电子泄漏，降低器件效率。直流电容分析表明ag-ZME具有高介电性能，使其能够选择性地将电子注入有机层的LUMO中，同时防止空穴的非发射直接还原。钙（II）甲氧基乙氧基氧化物（CME）也被用作EIL进行比较，尽管其具有很强的绝缘性能，但在ioled中表现出与ZME几乎相同的性能。利用ag-CME和ag-ZME中Ca（II）和Zn（II）的4s轨道来调节电子注入，这些见解提供了一种新的设计策略，使用非晶介电金属-有机薄膜作为EILs，可以产生高性能，柔性和稳定的电子器件，如ioled和钙钛矿太阳能电池。

The project aims to develop general methodologies for the precise control of functional inorganic thin films in their low temperature solution processing for the realization of roll-to-roll fabrication of flexible electronics. This year, it was found that solution-processed amorphous metal-organic thin film zinc(II) methoxyethoxide (ZME) acts as an efficient and stable electron injection layer (EIL) in inverted organic light-emitting diodes (iOLEDs). In contrast, crystallized ZnO obtained either by utilizing vacuum ultraviolet (VUV) light irradiation or by high temperature annealing caused a strong electron leakage, reducing device efficiency. DC capacitance analysis revealed that ag-ZME has a highly dielectric behavior, allowing it to selectively inject electrons into the LUMO of the organic layer while preventing non-emissive direct reduction of holes. Calcium(II) methoxyethoxide (CME) was also employed as an EIL for comparison and showed nearly the same performance as ZME in iOLEDs, despite its strongly insulating properties. The 4s orbitals of Ca(II) and Zn(II) in ag-CME and ag-ZME are used to regulate the electron injection, these insights offer a new design strategy that uses amorphous dielectric metal-organic thin films as EILs, which may yield high-performance, flexible, and stable electronic devices, such as iOLEDs and perovskite solar cells.