Bright and Ultralong Organic Phosphorescence via Sulfonic Acid Functionalization for High-Contrast Real-Time...

Area of Science:

• Organic optoelectronics
• Materials chemistry
• Photophysics

Background:

• Achieving high-efficiency, long-lifetime room-temperature phosphorescence (RTP) in pure organic materials remains challenging.
• Focus has been on phosphor skeletons, with less attention on functionalization's role in enhancing RTP performance.

Purpose of the Study:

• To investigate the impact of sulfonic acid functionalization on enhancing RTP properties of organic materials.
• To explore the potential of sulfonic acid-modified phosphors in optical imaging and optoelectronic devices.

Main Methods:

• Synthesized and characterized organic phosphors functionalized with sulfonic acid groups.
• Investigated the photophysical properties, including RTP efficiency and lifetime, in a poly(vinyl alcohol) (PVA) matrix.
• Evaluated the performance of the materials in optical imaging and light-writing display applications.

Main Results:

• Sulfonic acid functionalization led to bright and ultralong RTP, outperforming other substituents.
• The trigonal pyramidal structure and polarized S-O bonds of sulfonic acid groups enhanced intersystem crossing and minimized nonradiative dissipation.
• Achieved high transparency (>97%) PVA films with excellent optical imaging (contrast ratio 48.0, blurriness 0.24).
• Demonstrated full-color phosphorescence with high efficiency (Φ_P,max = 37.2%) and long lifetime (τ_P,max = 2.09 s).

Conclusions:

• Sulfonic acid functionalization is a highly effective strategy for developing high-performance organic RTP materials.
• This approach offers significant potential for next-generation intelligent optoelectronic materials, including advanced displays and imaging systems.