Quantum-dot light-emitting diode with ultrathin Au electrode embedded in solution-processed phosphomolybdic acid
Maciej Chrzanowski1, Mateusz Banski1, Piotr Sitarek1
1Department of Experimental Physics, Wroclaw University of Science and Technology Wybrzeze Wyspianskiego 27 50-370 Wroclaw Poland maciej.chrzanowski@pwr.edu.pl artur.p.podhorodecki@pwr.edu.pl.
RSC Advances
|May 6, 2022
Summary
Phosphomolybdic acid (PMA) enables cost-efficient MoO/Au/MoO (MAM) electrodes for quantum-dot light-emitting diodes (QLEDs). This MAM electrode offers high transmittance and low resistance, suitable for flexible optoelectronics.
Area of Science:
- Materials Science
- Optoelectronics
- Nanotechnology
Background:
- Transparent conductive films are crucial for optoelectronic devices.
- Indium tin oxide (ITO) is the standard but faces limitations in flexibility and cost.
- Alternative materials are needed for next-generation displays and lighting.
Purpose of the Study:
- To develop a cost-effective and flexible transparent electrode using phosphomolybdic acid (PMA).
- To investigate the MoO/Au/MoO (MAM) composite as a replacement for ITO and PEDOT:PSS in quantum-dot light-emitting diodes (QLEDs).
- To evaluate the performance and potential of MAM electrodes in flexible transparent optoelectronics.
Main Methods:
- Combined spin-coating and sputtering techniques for depositing MoO/Au/MoO (MAM) multilayer electrodes.
- Utilized phosphomolybdic acid (PMA) as a molybdenum oxide (MoO) source.
- Fabricated and characterized MAM-based QLEDs, including transmittance, sheet resistance, and efficiency measurements.
- Performed bending tests on MAM-coated polyethylene terephthalate (PET) substrates.
Main Results:
- Achieved high optical transmittance (79% at 550 nm) and low sheet resistance (22 Ω sq-1) for MAM electrodes.
- Demonstrated successful integration of MAM as both a transparent electrode and hole injection layer (HIL) in solution-processed QLEDs.
- MAM-based QLEDs exhibited a peak external quantum efficiency (EQE) of 2.7% and a maximum brightness of 12,000 cd m-2.
- MAM electrodes showed promising results for flexible applications after bending tests.
Conclusions:
- Phosphomolybdic acid (PMA) is an effective and economical precursor for fabricating high-performance MoO/Au/MoO (MAM) transparent electrodes.
- The MAM electrode can replace conventional ITO and PEDOT:PSS in QLEDs, enabling simpler fabrication and improved device performance.
- The developed MAM electrode is a viable candidate for flexible and transparent optoelectronic devices, including QLEDs.
