Enhancing color purity and efficiency of blue TADF OLEDs with MoO₃/Al₂O₃-based distributed Bragg reflector structures

Area of Science:

• Materials Science
• Organic Electronics
• Photophysics

Background:

• Blue thermally activated delayed fluorescence (TADF) organic light-emitting diodes (OLEDs) struggle with color purity and stability.
• Achieving efficient and stable deep-blue emission remains a key challenge in OLED technology.

Purpose of the Study:

• To enhance the performance of blue TADF OLEDs by integrating a novel distributed Bragg reflector (DBR).
• To improve color purity, operational stability, and efficiency of deep-blue OLED devices.

Main Methods:

• Fabrication of a distributed Bragg reflector (DBR) using molybdenum oxide and aluminum oxide via thermal evaporation and sputtering.
• Integration of the DBR structure into blue TADF OLED devices.
• Precise control over the number of DBR dyads to optimize optical properties.

Main Results:

• Improved device efficiency by up to 17.8% through DBR integration.
• Narrowed emission spectrum to a full width at half maximum (FWHM) of 54 nm, enhancing color purity.
• Achieved a peak emission wavelength of 462 nm for deep-blue light output.

Conclusions:

• The integration of a precisely controlled DBR is an effective strategy for enhancing blue TADF OLED performance.
• This approach successfully addresses key challenges in color purity and efficiency for deep-blue OLEDs.
• The developed DBR technology holds promise for next-generation stable and pure blue OLED displays and lighting.