Metal-Organic Frameworks Enable Spontaneous Singlet Oxygen Generation Without Light Irradiation

Area of Science:

• Materials Science
• Chemistry
• Nanotechnology

Background:

• Singlet oxygen (¹O₂) is a crucial reactive oxygen species (ROS) with diverse applications.
• Efficient and controlled generation of ¹O₂ is essential for advancing ROS-based technologies.
• Existing methods often require light irradiation, limiting applications in dark environments.

Purpose of the Study:

• To design and synthesize novel metal-organic frameworks (MOFs) capable of generating ¹O₂.
• To investigate the mechanism of light-free ¹O₂ generation from triplet oxygen (³O₂).
• To demonstrate the utility of the synthesized MOFs in practical applications.

Main Methods:

• Synthesis of isostructural MOFs, designated JNU-300.
• Electron paramagnetic resonance (EPR) spectroscopy for ¹O₂ detection.
• Probe experiments to confirm ¹O₂ selectivity.
• Mechanistic studies involving oxygen adsorption and polarization.

Main Results:

• JNU-300 MOFs were successfully synthesized and demonstrated spontaneous ¹O₂ generation.
• ¹O₂ generation occurs via direct activation of atmospheric ³O₂ without external light.
• The generated ¹O₂ effectively facilitated aerobic oxidation of sulfides and exhibited antibacterial properties.
• Mechanism elucidated the role of framework structure and coordination units in O₂ activation.

Conclusions:

• JNU-300 represents the first MOF material capable of light-free ¹O₂ generation at room temperature.
• This discovery offers a novel pathway for designing functional MOFs for ¹O₂ production.
• Opens new avenues for applications requiring ¹O₂ generation in dark conditions.