基于LiF修饰层的喷墨打印钙钛矿发光二极管

Inkjet Printed Perovskite Light-emitting Diode Based on LiF Modification Layer

金属卤化物钙钛矿材料由于具有高光致发光量子产率、高色纯度、带隙可调等优良光学性能,作为发光材料广泛用于制备钙钛矿电致发光二极管(PeLEDs)。虽然已经取得了较好的研究进展,但是其大面积商业化的进程还比较缓慢,尚需进一步研究。为了实现钙钛矿薄膜发光二极管的大面积制备,本文使用喷墨打印技术,研究了不同基板结构对于钙钛矿前驱液的铺展与结晶成膜的影响及器件性能的比较,引入了具有空穴阻挡能力的无机小分子材料氟化锂(LiF)作为缓冲层沉积于空穴传输层TFB上,获得了像素化的均匀分布的钙钛矿薄膜,从而得到发光均匀的最高亮度为4861 cd/m2且最大电流效率为5.41 cd/A的印刷钙钛矿发光二极管。研究表明,LiF修饰层对于空穴的注入具有阻挡作用,并且有效阻止了钙钛矿发光层与TFB接触后所导致的激子猝灭现象。

Metal halide perovskite materials are widely used as luminescent materials to prepare perovskite light-emitting diodes(PeLEDs)due to their outstanding optical properties such as high photoluminescence quantum yield,high color purity,and adjustable band gap.Although good research progress has been made,its large-scale preparation for commercialization is still very slow,and further efforts are needed.In order to realize the large-area preparation of perovskite thin film lightemitting diodes,this paper uses inkjet printing technology to study the influence of different substrate structures on the spreading and crystallization of the perovskite precursor liquid and the comparison of device performance.Then a kind of inorganic small molecule material lithium fluoride(LiF)with hole blocking ability was introduced as a buffer layer and deposited on TFB to obtain a pixelated and evenly distributed perovskite film,so that the highest brightness with uniform light emission was obtained.And we get a printed perovskite light-emitting diode with 4861cd/m2 and a maximum current efficiency of 5.41 cd/A.The studies showed that the LiF buffer layer has a certain blocking effect on the injection of holes,and effectively prevents the exciton quenching caused by the contact between the perovskite luminescent layer and the TFB after plasma treatment.