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Title: Highly-oriented one-dimensional MOF-semiconductor nanoarrays for efficient photodegradation of antibiotics
The ineffective removal of antibiotics from the aquatic environment has raised serious problems, including chronic toxicity and antibiotic resistance. Among the numerous strategies, photocatalytic degradation appears to be one of the promising methods to remove antibiotics. Semiconductors are the most widely used photocatalysts, whereas, their efficiencies still suffer from limited light absorption and poor charge separation. Given their exceptional properties, including a superior surface area and massive active sites, MOFs are excellent candidates for the formation of hierarchical nanostructures with semiconductors to address the above issues. In this study, highly-oriented one-dimensional (1D) MIL-100(Fe)/TiO 2 nanoarrays were developed as photocatalysts for the first time (MIL = Materials Institute Lavoisier). The 1D structured TiO 2 nanoarrays not only enable the direct and enhanced charge transport, but also permit easy recycling. With the in situ growth of MIL-100(Fe) on the TiO 2 nanoarrays, the composite exhibits enhanced light absorption, electron/hole separation, and accessibility of active sites. As a result, up to 90.79% photodegradation efficiency of tetracycline, a representative antibiotic, by the MIL-100(Fe)/TiO 2 composite nanoarrays was achieved, which is much higher than that of pristine TiO 2 nanoarrays (35.22%). It is also worth mentioning that the composite nanoarrays demonstrate high stability and still exhibit high efficiency twice that of the pristine TiO 2 nanoarrays even in the 5th run. This study offers a new strategy for the degradation of antibiotics by using 1D MOF-based nanocomposite nanoarrays.  more » « less
Award ID(s):
1727553
NSF-PAR ID:
10067165
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Catalysis Science & Technology
Volume:
8
Issue:
8
ISSN:
2044-4753
Page Range / eLocation ID:
2117 to 2123
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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