Integrated Soft Porosity and Electrical Properties of Conductive‐on‐Insulating Metal‐Organic Framework Nanocrystals

• Published in: Angewandte Chemie International Edition Vol. 62; no. 35; pp. e202303903 - n/a
• Main Authors: Yao, Ming‐Shui, Otake, Ken‐ichi, Zheng, Jiajia, Tsujimoto, Masahiko, Gu, Yi‐Fan, Zheng, Lu, Wang, Ping, Mohana, Shivanna, Bonneau, Mickaele, Koganezawa, Tomoyuki, Honma, Tetsuo, Ashitani, Hirotaka, Kawaguchi, Shogo, Kubota, Yoshiki, Kitagawa, Susumu
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 28.08.2023
• Edition: International ed. in English
• Subjects: Carbon dioxide; Conductivity; Electrical properties; Flexible structures; Heterostructures; Hybridization; Metal-organic frameworks; Nanocrystals; Operando; Porosity; Shape Memory; Soft Porosity; Synchrotrons; Conductivity; Operando; Metal-Organic Frameworks; Shape Memory; Soft Porosity
• DOI: 10.1002/anie.202303903
• ISSN: 1433-7851; 1521-3773

A one‐stone, two‐bird method to integrate the soft porosity and electrical properties of distinct metal–organic frameworks (MOFs) into a single material involves the design of conductive‐on‐insulating MOF (cMOF‐on‐iMOF) heterostructures that allow for direct electrical control. Herein, we report the synthesis of cMOF‐on‐iMOF heterostructures using a seeded layer‐by‐layer method, in which the sorptive iMOF core is combined with chemiresistive cMOF shells. The resulting cMOF‐on‐iMOF heterostructures exhibit enhanced selective sorption of CO2 compared to the pristine iMOF (298 K, 1 bar, S CO2/H2 ${{_{{\rm CO}{_{2}}/{\rm H}{_{2}}}$ from 15.4 of ZIF‐7 to 43.2–152.8). This enhancement is attributed to the porous interface formed by the hybridization of both frameworks at the molecular level. Furthermore, owing to the flexible structure of the iMOF core, the cMOF‐on‐iMOF heterostructures with semiconductive soft porous interfaces demonstrated high flexibility in sensing and electrical “shape memory” toward acetone and CO2. This behavior was observed through the guest‐induced structural changes of the iMOF core, as revealed by the operando synchrotron grazing incidence wide‐angle X‐ray scattering measurements. Owing to the integration of soft porosity and electrical properties, conductive‐on‐insulating metal–organic framework (cMOF‐on‐iMOF) heterostructured nanocrystals (with the semiconductive soft porous interfaces) show enhanced selective sorption toward CO2, electrical gating, and “shape memory” effects for the guest responsive iMOF core, as revealed by operando synchrotron measurements.