Improving operation lifetime of OLED by using thermally activated delayed fluorescence as host

Abstract

We fabricated organic light-emitting diodes (OLEDs) with the thermally activated delayed fluorescence (TADF) material of 4CzIPN, which show better stability compared with the 4,4’-Bis(carbazol-9-yl)biphenyl (CBP) based devices. The half lifetime of the device using 4CzIPN as host material has doubled, and a slower voltage rise compared with that of CBP-based devices has been achieved, which indicates the improvement of stability. We attribute the better stability to the good film morphology and difficult crystallization property of 4CzIPN. Our results suggest that employing the 4CzIPN as host material can be a promising way of fabricating OLEDs with longer operation lifetime.

References

[1] TangC W, VanSlykeS A. Applied Physics Letters, 1987, 51: 913

[2] TangC W, VanSlykeS A, ChenC H. Journal of Applied Physics, 1989, 65: 3610

[3] GigliG, BarbarellaG, FavarettoL. Applied Physics Letters, 1999, 75: 439

[4] WangX, RundleP, BaleM. Synthetic Metals, 2003, 137: 1051

[5] ChaskarA, ChenH F, WongK T. Adv. Mater., 2011, 23: 3876

[6] GongS, FuQ, WangQ. Adv. Mater., 2011, 23: 4956

[7] HungW Y, WangT C, ChiuH C. Phys. Chem. Chem. Phys., 2010, 12: 10685

[8] JeonS O, LeeJ Y J Mater. Chem., 2012, 22: 4233

[9] SasabeH, SeinoY, KimuraM. Chemistry of Materials, 2012, 24: 1404

[10] JiangZ, XuX, ZhangZ. Journal of Materials Chemistry, 2009, 19: 7661

[11] TaoY, YangC, QinJ. Chem. Soc. Rev., 2011, 40: 2943

[12] AddyD, JolandaB, NicoleK. Journal of the American Chemical Society, 2004, 126: 7718

[13] KlemensB, AddyD, HerbertB. Journal of the American Chemical Society, 2004, 126: 6035

[14] GaoC H, CaiS D, GuW. ACS Appl. Mater. Interfaces, 2012, 4: 5211

[15] SuzukiY, ZhangQ, AdachiC. J. Mater. Chem. C, 2015, 3: 1700

[16] ZhangL, DongS-C, GaoC-H. Applied Physics A, 2014, 118: 381

[17] WangS, ZhangY, ChenW. Chem. Commun., 2015, 51: 11972

[18] ChoY J, YookK S, LeeJ Y. Adv. Mater., 2014, 26: 4050

[19] TsaiM H, HongY H, ChangC H. Adv. Mater., 2007, 19: 862

[20] SoF, KondakovD. Adv. Mater., 2010, 22: 3762