光谱学与光谱分析
光譜學與光譜分析
광보학여광보분석
SPECTROSCOPY AND SPECTRAL ANALYSIS
2014年
2期
322-326
,共5页
有机电致发光器件%磷光%间隔层
有機電緻髮光器件%燐光%間隔層
유궤전치발광기건%린광%간격층
Organic light-emitting diodes%Phosphor%Spacer layer
制备了结构为ITO/MoO3(40 nm)/NPB(40 nm)/TCTA(10 nm)/CBP∶GIr1(14%)∶ R-4B(2%)(20 nm)/间隔层(3 nm)/CBP∶GIr1(14%)∶R-4B(2%)(10 nm)/BCP(10 nm)/Alq3(40 nm)/LiF(1 nm)/Al(100 nm)的有机电致发光器件,间隔层分别为CBP ,TCTA ,TPBI和BCP ,GIr1和R-4B分别为绿红磷光材料。通过加入不同间隔层来调控载流子和激子在发光层内的分布并研究了其对器件发光性能的影响。研究表明TCTA ,TPBI和BCP分别作为间隔层的器件较CBP为间隔层的参考器件,电压为6 V时,电流效率分别高出59%,79%和93%,以BCP为间隔层的器件效率最高达到22.58 cd · A -1;TPBI和BCP为间隔层相对于以TCTA为间隔层的器件,在较高的电流密度下,效率滚降更小。分析原因TCTA间隔层较高的LUMO能级和三线态能量将电子和激子限制在较窄的复合区域,提高了载流子相遇形成激子的概率,在较高电流密度下猝灭也更严重;TPBI和BCP由于具有较高的HOMO能级和电子传输能力,拓宽了激子的复合区域。间隔层引起电子或空穴的累积,形成较高的空间电场,有利于发光层相应载流子的注入与传输。由于发光层掺杂方式为红绿共掺,器件均获得了较好的色坐标稳定性。
製備瞭結構為ITO/MoO3(40 nm)/NPB(40 nm)/TCTA(10 nm)/CBP∶GIr1(14%)∶ R-4B(2%)(20 nm)/間隔層(3 nm)/CBP∶GIr1(14%)∶R-4B(2%)(10 nm)/BCP(10 nm)/Alq3(40 nm)/LiF(1 nm)/Al(100 nm)的有機電緻髮光器件,間隔層分彆為CBP ,TCTA ,TPBI和BCP ,GIr1和R-4B分彆為綠紅燐光材料。通過加入不同間隔層來調控載流子和激子在髮光層內的分佈併研究瞭其對器件髮光性能的影響。研究錶明TCTA ,TPBI和BCP分彆作為間隔層的器件較CBP為間隔層的參攷器件,電壓為6 V時,電流效率分彆高齣59%,79%和93%,以BCP為間隔層的器件效率最高達到22.58 cd · A -1;TPBI和BCP為間隔層相對于以TCTA為間隔層的器件,在較高的電流密度下,效率滾降更小。分析原因TCTA間隔層較高的LUMO能級和三線態能量將電子和激子限製在較窄的複閤區域,提高瞭載流子相遇形成激子的概率,在較高電流密度下猝滅也更嚴重;TPBI和BCP由于具有較高的HOMO能級和電子傳輸能力,拓寬瞭激子的複閤區域。間隔層引起電子或空穴的纍積,形成較高的空間電場,有利于髮光層相應載流子的註入與傳輸。由于髮光層摻雜方式為紅綠共摻,器件均穫得瞭較好的色坐標穩定性。
제비료결구위ITO/MoO3(40 nm)/NPB(40 nm)/TCTA(10 nm)/CBP∶GIr1(14%)∶ R-4B(2%)(20 nm)/간격층(3 nm)/CBP∶GIr1(14%)∶R-4B(2%)(10 nm)/BCP(10 nm)/Alq3(40 nm)/LiF(1 nm)/Al(100 nm)적유궤전치발광기건,간격층분별위CBP ,TCTA ,TPBI화BCP ,GIr1화R-4B분별위록홍린광재료。통과가입불동간격층래조공재류자화격자재발광층내적분포병연구료기대기건발광성능적영향。연구표명TCTA ,TPBI화BCP분별작위간격층적기건교CBP위간격층적삼고기건,전압위6 V시,전류효솔분별고출59%,79%화93%,이BCP위간격층적기건효솔최고체도22.58 cd · A -1;TPBI화BCP위간격층상대우이TCTA위간격층적기건,재교고적전류밀도하,효솔곤강경소。분석원인TCTA간격층교고적LUMO능급화삼선태능량장전자화격자한제재교착적복합구역,제고료재류자상우형성격자적개솔,재교고전류밀도하졸멸야경엄중;TPBI화BCP유우구유교고적HOMO능급화전자전수능력,탁관료격자적복합구역。간격층인기전자혹공혈적루적,형성교고적공간전장,유리우발광층상응재류자적주입여전수。유우발광층참잡방식위홍록공참,기건균획득료교호적색좌표은정성。
We have investigated the performances of organic light-emitting diodes (OLED) with different spacer ,the structure was fabricated as ITO/MoO3 (40 nm)/NPB(40 nm)/TCTA(10 nm)/CBP∶GIr114% ∶R-4B2% (30 nm)/spacer (3 nm)/CBP∶GIr114% ∶R-4B2% (30 nm)/BCP(10 nm)/Alq3 (40 nm)/LiF(1 nm)/Al(100 nm) ,the spacers were CBP ,TCTA ,TPBI and BCP separately ,GIr1 and R-4B were green and red phosphorescent dye respectively .The results showed that compared to the reference device utilized CBP as the spacer layer ,TCTA ,TPBI and BCP had higher current efficiency in excess of 59% ,79%and 93% ,the maximum current efficiency of 16 .91 cd · A -1 was achieved with BCP as the spacer at voltage of 5 V ,TPBI and BCP as the spacer layer obtained the higher current density and lower efficiency roll-off .We attributed to these results to the fol-low reasons ,the first was that carriers and excitons were limited to a narrow recombination region because of TCTA with higher LUMO energy level and triplet energy ,which improved the probability of carriers recombination ,in addition ,more serious quenching at higher current density .The second reason was that TPBI and BCP had the higher HOMO energy level and electron mobility ,which broadened excitons recombination zone .In addition ,the spacer layer caused the accumulation of electrons or holes and the formation of high space electric field ,leading to carrier injection and transport more effectively .In particular ,we obtained a better stability of phosphorescent organic light-emitting diodes since the way for the red and green co-doped with host material .