Experimental and theoretical studies of Znq2 thin film fabricated by spin-coating and its characterisation as an active layer in OLED

• Autorzy: Sypniewska Malgorzata , Brumboiu Iulia E. , Kaczmarek-Kedziera Anna , Pokladko-Kowar Monika , Gondek Ewa , Popielarski Pawel , Szczęsny Robert , Derkowska-Zielinska Beata

Identyfikatory

DOI

10.24425/opelre.2025.154747

• Języki publikacji: EN

Abstrakty

EN

Bis(8-hydroxyquinoline) zinc dispersed in a poly(N-vinylcarbazole) matrix (Znq₂:PVK) was characterised for its possible use as an active layer in organic light-emitting diodes. The composition and morphology of Znq₂:PVK thin films deposited on quartz substrates was analysed by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and confocal microscopy. Optical properties of the films were characterised by absorption spectroscopy and photoluminescence and explained on the basis of calculated molecular properties of gas phase Znq₂, N-vinylcarbazole pentamer, and molecular models for the Znq₂:PVK interface. FTIR measurements of the Znq₂:PVK film revealed the presence of water, likely due to the formation of Znq₂-dihydrate during the fabrication process. Water could be removed by annealing films at 130 °C for 1 h and the annealed films showed better photoluminescence in the Znq₂ emission region. Finally, two diodes with an ITO/PEDOT:PSS/Znq2:PVK/Al structure were fabricated, where in the second one, the ITO/PEDOT:PSS/Znq₂:PVK layers were annealed at 130 °C. The first diode was characterised by a maximum brightness of about 83 cd/m² and a current efficiency of 0.12 cd/A, while the diode whose structure was annealed had a maximum brightness of about 219 cd/m² and a current efficiency of 0.26 cd/A.

Słowa kluczowe

EN

thin films; bis(8-hydroxyquinoline) zinc; photoluminescence; electroluminescence; organic light-emitting diodes

• Wydawca: Stowarzyszenie Elektryków Polskich ; Polska Akademia Nauk ; Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
• Czasopismo: Opto-Electronics Review
• Rocznik: 2025
• Tom: Vol. 33, No. 3
• Strony: art. no. e154747
• Opis fizyczny: Bibliogr. 44 poz., rys., wykr.

Twórcy

autor

Sypniewska Malgorzata

• Division of Surface Science, Faculty of Chemical Technology and Engineering, Bydgoszcz University of Science and Technology, Al. Prof. S. Kaliskiego 7, 85-796 Bydgoszcz, Poland
• Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Toruń, ul. Grudziądzka 5, Toruń 87-100, Poland

• https://orcid.org/0000-0002-6425-1103

autor

Brumboiu Iulia E.

• Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Toruń, ul. Grudziądzka 5, Toruń 87-100, Poland

• https://orcid.org/0000-0003-1671-8298

autor

Kaczmarek-Kedziera Anna

• Faculty of Chemistry, Nicolaus Copernicus University in Toruń, ul. Gagarina 7, Toruń 87-100, Poland

• https://orcid.org/0000-0002-4931-8701

autor

Pokladko-Kowar Monika

• Department of Physics, Cracow University of Technology, ul. Podchorążych 1, 30-084 Kraków, Poland

• https://orcid.org/0000-0002-8413-5185

autor

Gondek Ewa

• Department of Physics, Cracow University of Technology, ul. Podchorążych 1, 30-084 Kraków, Poland

• https://orcid.org/0000-0002-3692-1253

autor

Popielarski Pawel

• Department of Physics, Kazimierz Wielki University in Bydgoszcz, ul. Powstańców Wielkopolskich 2, 85-090 Bydgoszcz, Poland

• https://orcid.org/0000-0003-1868-3690

autor

Szczęsny Robert

• Faculty of Chemistry, Nicolaus Copernicus University in Toruń, ul. Gagarina 7, Toruń 87-100, Poland

• https://orcid.org/0000-0002-6313-9574

autor

Derkowska-Zielinska Beata

• Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Toruń, ul. Grudziądzka 5, Toruń 87-100, Poland

• https://orcid.org/0000-0002-0269-2771

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Uwagi

Opracowanie rekordu ze środków MNiSW, umowa nr POPUL/SP/0154/2024/02 w ramach programu "Społeczna odpowiedzialność nauki II" - moduł: Popularyzacja nauki (2025).