TY - JOUR
T1 - Small-size graphene oxide (GO) as a hole injection layer for high-performance green phosphorescent organic light-emitting diodes
AU - Miao, Yanqin
AU - Yin, Mengna
AU - Wang, Chengqiang
AU - Wei, Xiaozhen
AU - Wang, Zhiyuan
AU - Zhao, Min
AU - Wang, Yiwen
AU - Jia, Zhigang
AU - Wang, Hua
AU - Zhu, Furong
N1 - Funding Information:
This work was financially supported by National Natural Scientific Foundation of China (Grant No. 61705156, 61705158 and 62074109), Key R&D program of Shanxi Province (International Cooperation, 201903D421087), Key R&D program of Shanxi Province (201903D121100), and Program for the Innovative Talents of Higher Education Institutions of Shanxi.
Publisher Copyright:
© The Royal Society of Chemistry 2021.
PY - 2021/9/28
Y1 - 2021/9/28
N2 - In this work, we successfully synthesized small-size GO with the main size distribution at 200-400 nm using the tip sonication-assisted liquid-phase exfoliation method, which shows a suitable work function of 5.16 eV (annealing at 120 °C) well matching the ITO anode (4.80 eV) and extremely high transmittance (>98%, small size GO film spin-coated at 0.75 mg mL−1GO dispersion). Using small-size GO as hole injection materials, Ir(ppy)3-based green phosphorescent organic light-emitting diodes (OLEDs) were demonstrated, and the resulting devices exhibit a lower turn-on voltage of 3.0 V than the PEDOT:PSS-based device (3.3 V). Further, the optimized GO-based OLED achieves maximum current efficiency, power efficiency, and external quantum efficiency reaching 73.14 cd A−1, 53.95 lm W−1, and 20.63%, respectively, which are significantly higher than the PEDOT:PSS-based reference device (68.82 cd A−1, 48.04 lm W−1, and 19.44%). It was demonstrated that effective holes injection capability and excellent film-forming properties for small-size GO guarantee the achievement of such high device performance. All relevant results indicate that the use of small-size GO as a hole injection material has great potential to alternative PEDOT:PSS in OLEDs.
AB - In this work, we successfully synthesized small-size GO with the main size distribution at 200-400 nm using the tip sonication-assisted liquid-phase exfoliation method, which shows a suitable work function of 5.16 eV (annealing at 120 °C) well matching the ITO anode (4.80 eV) and extremely high transmittance (>98%, small size GO film spin-coated at 0.75 mg mL−1GO dispersion). Using small-size GO as hole injection materials, Ir(ppy)3-based green phosphorescent organic light-emitting diodes (OLEDs) were demonstrated, and the resulting devices exhibit a lower turn-on voltage of 3.0 V than the PEDOT:PSS-based device (3.3 V). Further, the optimized GO-based OLED achieves maximum current efficiency, power efficiency, and external quantum efficiency reaching 73.14 cd A−1, 53.95 lm W−1, and 20.63%, respectively, which are significantly higher than the PEDOT:PSS-based reference device (68.82 cd A−1, 48.04 lm W−1, and 19.44%). It was demonstrated that effective holes injection capability and excellent film-forming properties for small-size GO guarantee the achievement of such high device performance. All relevant results indicate that the use of small-size GO as a hole injection material has great potential to alternative PEDOT:PSS in OLEDs.
UR - https://www.scopus.com/pages/publications/85115821438
U2 - 10.1039/D1TC02898G
DO - 10.1039/D1TC02898G
M3 - Journal article
SN - 2050-7526
VL - 9
SP - 12408
EP - 12419
JO - Journal of Materials Chemistry C
JF - Journal of Materials Chemistry C
IS - 36
ER -