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Abstract Metal–organic frameworks (MOFs) are hybrid materials known for their nanoscale pores, which give them high surface areas but generally lead to poor electrical conductivity. Recently, MOFs with high electrical conductivity were established as promising materials for a variety of applications in energy storage and catalysis. Many recent reports investigating the fundamentals of charge transport in these materials focus on the role of the organic ligands. Less consideration, however, is given to the metal ion forming the MOF, which is almost exclusively a late first‐row transition metal. Here, we report a moderately conductive porous MOF based on trivalent gallium and 2,3,6,7,10,11‐hexahydroxytriphenylene. Gallium, a metal that has not been featured in electrically conductive MOFs so far, has a closed‐shell electronic configuration and is present in its trivalent state—in contrast to most conductive MOFs, which are formed by open‐shell, divalent transition metals. Our material, made without using any harmful solvents, displays conductivities on the level of 3 mS/cm and a surface area of 196 m2/g, comparable to transition metal analogs.
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Redox Chemistry Mediated Control of Morphology and Properties in Electrically Conductive Coordination Polymers: Opportunities and Challenges
Coordination polymers (CPs) and metal–organic frameworks (MOFs) have attracted significant research interest in the past several decades due to their reticular structures and modularity. However, realizing electrically conductive CPs or MOFs with comparable properties to classic conducting organic polymers has only been a recent development. This emerging class of materials has found wide application in many fields due to the combined features of structural rigidity, chemical tunability, porosity, and charge transport. Alongside many studies revealing myriad design approaches to access these materials, the role that redox chemistry plays in both material synthesis and modulation of electronic properties has been an emerging theme. This Perspective provides a brief overview of select examples where redox chemistry mediates the control of morphology and properties in electrically conductive CPs/MOFs. The challenges and limitations in this area are also discussed. Particular challenges include the characterization of redox states in these materials and measuring and understanding highly correlated electronic properties and other unusual physical phenomena that may be important for potential applications.
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- PAR ID:
- 10527464
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- Chemistry of Materials
- Volume:
- 36
- Issue:
- 9
- ISSN:
- 0897-4756
- Page Range / eLocation ID:
- 3999 to 4010
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acs.chemmater.4c00101
