基于改性空穴注入层与复合发光层的高效钙钛矿发光二极管

有机金属卤化钙钛矿作为发射体具有极高的色纯度和极低的成本,但钙钛矿层普遍较差的形貌制约了器件的性能.引入合适的聚合物可有效改善旋涂型钙钛矿薄膜的均匀性.本文引入聚(4-苯乙烯磺酸盐)(PSS)改性的聚(3,4-乙撑二氧噻吩):PSS(PEDOT:PSS)作为空穴注入层(HIL),结合一步旋涂制备的三溴化铅甲基胺(MAP...

Perovskite light-emitting diode based on combination of modified hole-injection layer and polymer composite emission layer

Appreciable progress of organometal halide perovskite materials has been achieved in recent years due to their controllable synthesis and excellent optoelectronic properties.And the potential uses of these perovskites in photovoltaics,light-emitting diodes(LEDs),photodetectors and lasers have been successfully demonstrated.Although organometal halide perovskites appear as emitters with extremely high color purity and low cost,the device performance is significantly limited by poor morphology of the perovskite layer.The addition of the polymer into the perovskite layer is a convenient and effective method to improve the homogeneity of the spincoated perovskite film.In this work,we fabricate green perovskite light emitting diodes(PeLEDs)with poly(styrenesulfonate)(PSS)-modified poly(3,4-ethylenedioxythiophene):PSS(PEDOT:PSS)as the hole injection layer(HIL)and a single spin coating composite film consisting of methylammonium lead tribromide(MAPbBr3)and poly(ethylene oxide)(PEO)as the emissive layer.The PSS doping increases the work function of PEDOT:PSS and reduces the injection barrier between PEDOT:PSS HIL and MAPbBr3 perovskite,thus balancing the carriers within the PeLEDs.The PEO doping enables the MAPbBr3 to become a dense and uniform perovskite film with a~100%coverage.With the above approaches,highly efficient PeLEDs with maximum luminance and current efficiency of 2476 cd·m^-2 and 7.6 cd·A^-1 are eventually acquired.This work provides a method of fabricating the high-coverage and high-efficiency PeLEDs.