On the performance of polymer-inorganic perovskite oxide composite light-emitting diodes: The effect of perovskite SrTiO3 additives

Ummi Kalsom Noor Din,Ahmad Rifqi Md Zain,Akrajas Ali Umar,Tengku Hasnan Tengku Aziz,Mohd Ambri Mohamed,Muhamad Mat Salleh

doi:10.1177/1847980420987774

Ummi Kalsom Noor Din, Ahmad Rifqi Md Zain + Show 4 more

Open Access

https://doi.org/10.1177/1847980420987774

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Abstract

This study reports the performances of a single structured light-emitting diode (LED) devices based on polymer material poly(9,9-di- n-hexylfluorenyl-2,7-diyl) (PHF) mixed with various concentrations of perovskite oxide strontium titanate (SrTiO3) particles deposited as a composite PHF: SrTiO3 emitting layer. The performances of the single structured organic LED indium tin oxide (ITO)/PHF/aluminum (Al) device and the composite LED ITO/PHF: SrTiO3/Al devices were compared in terms of turn-on voltage and luminance intensity. By incorporating perovskite SrTiO3 particles into PHF emitting layer, the turn-on voltage of the device is significantly reduced from 11.25 V to 1.80 V and the luminance intensity increased from 57.7 cd/m2 to 609 cd/m2. The improvement of turn-on voltage and the electroluminescence spectrum of the composite devices were found to be dependent on the weight ratios of SrTiO3 content in the PHF emitting layer.

Highlights

The development of organic light-emitting diodes (OLEDs) has been gaining great attention as researchers are searching for a novel approach to improve OLED performance in display systems and lighting sources
By incorporating perovskite SrTiO3 particles in the PHF-emitting layer, this study is expected to enhance the performance of composite polymer perovskite, PHF: SrTiO3 LED devices
Perovskite oxide SrTiO3 powder was synthesized at 180C temperature for 6 h using an alkali hydrothermal process.[26]

Summary

Introduction

The development of organic light-emitting diodes (OLEDs) has been gaining great attention as researchers are searching for a novel approach to improve OLED performance in display systems and lighting sources. Perovskite-structured materials have been extensively studied due to their extraordinary optoelectronic characteristics, such as synthetic bandgap tunability, high absorption coefficient, good photoconductivity, and long charge carrier diffusion length with higher lifetimes,[7,8,9] making perovskite materials great for diverse applications, including light-emitting diode (LED),[10,11,12] solar cells,[13,14,15,16] photocatalysis,[17] lasers,[18] and photodetectors.[19] According to recent research, the use of lead (Pb) halide perovskite structured materials in LED devices has been reported to deliver better LED performance.[20,21] the instability and toxicity of Pbbased perovskite are highly debated as risking human health and the ecosystem. It is an interesting alternative that incorporates perovskite oxide in the LED-emitting layer as a composite material. We fabricate LEDs of composites poly(9,9di-n-hexylfluorenyl-2,7-diyl) (PHF) with inorganic perovskite oxide SrTiO3 particles (Figure 1). By incorporating perovskite SrTiO3 particles in the PHF-emitting layer, this study is expected to enhance the performance of composite polymer perovskite, PHF: SrTiO3 LED devices

Materials and method

Results and discussion

Conclusions