Organic LEDs Based on Bis(8-hydroxyquinoline) Zinc Derivatives with a Styryl Group

Malgorzata Sypniewska; Monika Pokladko-Kowar; Ewa Gondek; Aleksandra Apostoluk; Piotr Kamedulski; Vitaliy Smokal; Peng Song; Junyan Liu; Robert Szczesny; Beata Derkowska-Zielinska

doi:10.3390/molecules28217435

Organic LEDs Based on Bis(8-hydroxyquinoline) Zinc Derivatives with a Styryl Group

Molecules. 2023 Nov 5;28(21):7435. doi: 10.3390/molecules28217435.

Authors

Affiliations

¹ Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Torun, Grudziadzka 5, 87-100 Torun, Poland.
² Department of Physics, Cracow University of Technology, Podchorążych Str. 1, 30-084 Krakow, Poland.
³ Institut des Nanotechnologies de Lyon (INL-UMR5270), Université de Lyon, INSA-Lyon, ECL, UCBL, CPE, CNRS, 69621 Villeurbanne, France.
⁴ Faculty of Chemistry, Nicolaus Copernicus University in Torun, Gagarina 7, 87-100 Torun, Poland.
⁵ Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, Wilenska 4, 87-100 Torun, Poland.
⁶ Department of Chemistry, Taras Shevchenko National University of Kyiv, 60 Volodymyrska, 01033 Kyiv, Ukraine.
⁷ State Key Laboratory of Robotics and System, Harbin Institute of Technology, Harbin 150001, China.
⁸ School of Instrumentation Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
⁹ School of Mechatronics Engineering, Harbin Institute of Technology, Harbin 150001, China.

Abstract

For the first time, organic light-emitting diodes (OLEDs) based on bis(8-hydroxyquinoline) zinc with a styryl group (ZnStq) dispersed in poly(N-vinylcarbazole) matrix (ZnStq_R:PVK, where R = H, Cl, OCH₃) were fabricated. The ZnStq_R:PVK films made via the spin-coating method were used as the active layer in these devices. The produced OLEDs showed strong electroluminescence with yellow emissions at 590, 587 and 578 nm for the ZnStq_H:PVK, ZnStq_Cl:PVK and ZnStq_OCH₃:PVK, respectively. For all the studied thin films, the main photoluminescence emission bands were observed between 565 and 571 nm. The OLED with the ZnStq_OCH₃:PVK layer with a narrow electroluminescence spectrum was found to have sufficient color purity to produce ultra-high-resolution displays with reduced power consumption (full width at half maximum of 59 nm, maximum brightness of 2244 cd/m² and maximum current efficiency of 1.24 cd/A, with a turn-on voltage of 6.94 V and a threshold voltage of 7.35 V). To characterize the photophysical properties of the active layer, the ZnStq_R:PVK layers samples were additionally deposited on glass and silicon substrates. We found that the obtained results predestine ZnStq_R:PVK layers for use in the lighting industry in the future.

Keywords: OLED; absorption coefficient; bis(8-hydroxyquinoline) zinc derivatives; ellipsometry; photo- and electroluminescence; refractive index; thin films.

Abstract

Grants and funding