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Abstract Metal–organic frameworks (MOFs) with mobile charges have attracted significant attention due to their potential applications in photoelectric devices, chemical resistance sensors, and catalysis. However, fundamental understanding of the charge transport pathway within the framework and the key properties that determine the performance of conductive MOFs in photoelectric devices remain underexplored. Herein, we report the mechanisms of photoinduced charge transport and electron dynamics in the conductive 2D M−HHTP (M=Cu, Zn or Cu/Zn mixed; HHTP=2,3,6,7,10,11‐hexahydroxytriphenylene) MOFs and their correlation with photoconductivity using the combination of time‐resolved terahertz spectroscopy, optical transient absorption spectroscopy, X‐ray transient absorption spectroscopy, and density functional theory (DFT) calculations. We identify the through‐space hole transport mechanism through the interlayer sheet π–π interaction, where photoinduced hole state resides in HHTP ligand and electronic state is localized at the metal center. Moreover, the photoconductivity of the Cu−HHTP MOF is found to be 65.5 S m−1, which represents the record high photoconductivity for porous MOF materials based on catecholate ligands.
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Pyrogallate‐Based Metal‐Organic Framework with a Two‐Dimensional Secondary Building Unit
Abstract We report a metal–organic framework (MOF) with a rare two‐dimensional (2D) secondary building unit (SBU). The SBU comprises mixed‐valent Fe2+and Fe3+metal ions bridged by oxygen atoms pertaining to the polytopic ligand 3,3′,4,4′,5,5′‐hexahydroxybiphenyl, which also define the iron‐oxide 2D layers. Overall, the anionic framework exhibits rare topology and evidences strong electronic communication between the mixed‐valence iron sites. These results highlight the importance of dimensionality control of MOF SBUs for discovering new topologies in reticular chemistry, and especially for improving electronic communication within the MOF skeleton.
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- Award ID(s):
- 2105495
- PAR ID:
- 10382546
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 61
- Issue:
- 49
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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