A Light‐Responsive Metal–Organic Framework Hybrid Membrane with High On/Off Photoswitchable Proton Conductivity

• Published in: Angewandte Chemie International Edition Vol. 59; no. 20; pp. 7732 - 7737
• Main Authors: Liang, Hong‐Qing, Guo, Yi, Shi, Yanshu, Peng, Xinsheng, Liang, Bin, Chen, Banglin
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 11.05.2020
• Edition: International ed. in English
• Subjects: Chemical sensors; Conductivity; Electronic devices; Electronic equipment; Fuel cells; hybrid membranes; Irradiation; Light irradiation; Membranes; Metal-organic frameworks; Mimicry; MOFs; photoswitching; proton conduction; Protons; Radiation; Remote sensors; Response time; Sensors; Spiropyrans; sulfonated spiropyran; Transistors; proton conduction; MOFs; hybrid membranes; photoswitching; sulfonated spiropyran
• ISSN: 1433-7851; 1521-3773; 1521-3773
• DOI: 10.1002/anie.202002389

Mimicking biological proton pumps to achieve stimuli‐responsive protonic solids has long been of great interest for their diverse applications in fuel cells, chemical sensors, and bio‐electronic devices. Now, dynamic light‐responsive metal–organic framework hybrid membranes can be obtained by in situ encapsulation of photoactive molecules (sulfonated spiropyran, SSP), as the molecular valve, into the cavities of the host ZIF‐8. The configuration of SSP can be changed and switched reversibly in response to light, generating different mobile acidic protons and thus high on/off photoswitchable proton conductivity in the hybrid membranes and device. This device exhibits a high proton conductivity, fast response time, and extremely large on/off ratio upon visible‐light irradiation. This approach might provide a platform for creating emerging smart protonic solids with potential applications in the remote‐controllable chemical sensors or proton‐conducting field‐effect transistors. Light‐regulated proton conduction in MOF membranes was realized by in situ encapsulation of light‐active molecules into 3D frameworks. The hybrid membrane has high proton conductivity and outstanding switchable properties, making it feasible to control the lightening of a LED lamp assembled into an optically controlled circuit.