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Title: Microbial reduction of metal-organic frameworks enables synergistic chromium removal
Abstract Redox interactions between electroactive bacteria and inorganic materials underpin many emerging technologies, but commonly used materials (e.g., metal oxides) suffer from limited tunability and can be challenging to characterize. In contrast, metal-organic frameworks exhibit well-defined structures, large surface areas, and extensive chemical tunability, but their utility as microbial substrates has not been examined. Here, we report that metal-organic frameworks can support the growth of the metal-respiring bacteriumShewanella oneidensis, specifically through the reduction of Fe(III). In a practical application, we show that cultures containingS. oneidensisand reduced metal-organic frameworks can remediate lethal concentrations of Cr(VI) over multiple cycles, and that pollutant removal exceeds the performance of either component in isolation or bio-reduced iron oxides. Our results demonstrate that frameworks can serve as growth substrates and suggest that they may offer an alternative to metal oxides in applications seeking to combine the advantages of bacterial metabolism and synthetic materials.  more » « less
Award ID(s):
1720595
PAR ID:
10474977
Author(s) / Creator(s):
; ;
Publisher / Repository:
Nature
Date Published:
Journal Name:
Nature Communications
Volume:
10
Issue:
1
ISSN:
2041-1723
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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