A silane-based host material with improved electron transport properties for phosphorescent OLEDs with high efficiency and low efficiency roll-off  

作　　者：Jinho Park Junseop Lim Jun Yeob Lee 

机构地区：[1]School of Chemical Engineering,Sungkyunkwan University 2066,Seobu-ro,Jangan-gu,Suwon-si,Gyeonggi-do,16419,Republic of Korea

出　　处：《Science China Materials》2023年第5期1997-2003,共7页中国科学（材料科学（英文版）

基　　金：supported by the National Science Foundation of Korea(2020R1A2C2100872);the Ministry of Trade,Industry and Energy of Korea(20018956)。

摘　　要：A dibenzosilole-based host material was designed and characterized.The host material,9,9'-(5,5-diphenyl-5H-dibenzo[b,d]silole-2,8-diyl)bis(9H-carbazole)(SSiCz),was designed to enhance the electron transport properties and rigidity by coupling two phenyl units of the tetraphenyl silane of a strong hole transport type bis(4-(9Hcarbazol-9-yl)phenyl)diphenylsilane host.The device efficiency roll-off was improved considerably by balancing the carriers in the phosphorescent organic light-emitting diodes(PhOLEDs),and the driving voltage at high luminance was reduced.The red and green PhOLEDs exhibited high external quantum efficiencies(EQEs)of 23.8%and 24.9%,respectively,and a relieved efficiency roll-off.In addition,S-SiCz was used as an electron transport type host with a hole transport type3,3'-di(9H-carbazol-9-yl)-1,1'-biphenyl host.The maximum EQEs of the red and green PhOLEDs using the mixed host were 26.0%and 25.5%,respectively,and EQE roll-off values were 18%and 6%,respectively.Therefore,the planarization design strategy of the host is effective for better device performance.

关 键 词：OLEDS host material SILANE BIPOLAR phosphorescent OLEDs 

分 类 号：O627.41[理学—有机化学] TN383.1[理学—化学]