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

Abstract Singlet oxygen ( 1 O 2 ) is a widely used reactive oxygen species (ROS), making the development of new materials capable of efficiently generating it highly important. In this work, we report a series of isostructural metal‐organic frameworks (MOFs), named JNU‐300 (JNU = Jinan University), can spontaneously generate 1 O 2 by directly activating triplet oxygen ( 3 O 2 ) from the air without the need for additional light irradiation. The highly selective generation of 1 O 2 by JNU‐300 is verified by electron paramagnetic resonance (EPR) spectroscopy and probe experiments for 1 O 2 . The generated 1 O 2 can be employed for aerobic oxidation of sulfide and antibacterial application. Mechanism studies revealed that the framework structure, and the adsorption and polarization of O 2 by the coordination units of JNU‐300, are crucial for the 1 O 2 generation. To the best of our knowledge, MOFs JNU‐300 are the first MOF material capable of producing 1 O 2 by activating 3 O 2 in the absence of light at room temperature. This work provides new insights into the design and construction of functional MOF materials capable of generating 1 O 2 via activating 3 O 2 without light irradiation, opening new possibilities for their application in specialized fields that require 1 O 2 in the dark.