溶液加工型蒽类树枝状深蓝光材料的合成与表征  

Synthesis and characterization of solution-processible anthracene-based deep-blue fluorescent dendrimers

作　　者：赵磊[1,2] 王淑萌 丁军桥[1] 王利祥[1] 

机构地区：[1]中国科学院长春应用化学研究所,高分子物理与化学国家重点实验室,长春130022 [2]中国科学院大学,北京100049

出　　处：《科学通报》2016年第3期325-332,共8页Chinese Science Bulletin

基　　金：国家重点基础研究发展计划(2015CB655001);国家自然科学基金(21174144;51322308)资助

摘　　要：采用9,10-二苯蒽(DPA)作为中心核,一代至三代齐聚咔唑作为外围树枝,设计合成了一系列溶液加工型树枝状深蓝光荧光材料Ent1,Ent2和Ent3.不同于DPA容易在膜态下形成结晶,Ent1~Ent3均具有良好的热稳定性和形态稳定性,玻璃化转变温度高达194~371℃.同时,咔唑树枝的引入,有效地抑制了分子间的相互作用,使得膜态下荧光量子效率从Ent1的46%提高至Ent2的52%和Ent3的67%.通过旋涂工艺制备了深蓝光非掺杂器件,发现第二代树枝状荧光材料Ent2表现出最优器件性能,发光效率为2.63 cd/A,色坐标CIE_((x,y))为(0.16,0.10).Anthracene has been intensively studied as an attractive building block for deep-blue fluorescent emitters due to its wide band gap and high photoluminescence quantum yield （PLQY） in dilute solution. In solid state, however, these anthracene derivatives seem to aggregate or crystallize, leading to the quenched fluorescence, red-shifted emission and poor device lifetime. Therefore, there are few reports about anthracene-based deep-blue emitters suitable for solution-processed undoped devices. To this end, herein we have designed and synthesized a series of solution-processible deep-blue fluorescent dendrimers （Entl, Ent2 and Ent3） by using 9,10-diphenylanthracene （DPA） as the central core and 1st to 3rd generation oligocarbazole as the peripheral dendron. Unlike DPA that tends to crystallize in the solid state, Entl^Ent3 are thermally stable, showing very high glass transition temperatures up to 194-371~C without any related signals from the crystallization or melting processes. As determined by atomic force microscopy （AFM）, in addition, both the pristine and annealed films of Entl-Ent3 have a fairly smooth surface with a root-mean-square roughness of 0.33-0.47 nm, indicative of their morphology stability. Meanwhile, the introduction of dendrons can effectively suppress the intermolecular interactions and thus enhance the film PLQY from 46% of Entl to 52% of Ent2 and 67% of Ent3. Correspondingly, as a result of the much richer electron-cloud density from the higher generation dendron, the highest occupied molecular orbital （HOMO） energy level is increased from -5.51 eV of Entl to -5.37 eV of Ent2 and -5.34 eV of Ent3, which is beneficial for the hole injection. Solution-processed undoped organic light-emitting diodes （OLEDs） are subsequently fabricated with a configuration of ITOWEDOT：PSS（40 nm）kEntl-Ent3（40 nm）／TPBI（55 nm）kLiF（1 nm）kAl（100 nm）. All the dendrimers display a bright deep-blue emission with Commission International De L＇Eclairge （CIE） coordinates

关 键 词：9 10-二苯蒽 咔唑树枝 溶液加工 深蓝光荧光材料 非掺杂器件 

分 类 号：TQ422[化学工程]