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Title: Improved Hydrogen Sensitivity and Selectivity in PdO with Metal-Organic Framework Membrane

Metal-organic frameworks (MOFs) are highly designable porous materials and are recognized for their exceptional selectivity as chemical sensors. However, they are not always suitable for incorporation with existing sensing platforms, especially sensing modes that rely on electronic changes in the sensing material (e.g., work-function response or conductometric response). One way that MOFs can be utilized is by growing them as a porous membrane on a sensing layer and using the MOF to affect the electronic structure of the sensing layer. In this paper, a proof-of-concept for electronic modulation with MOFs is demonstrated. A PdO nanoparticle sensing layer on a chemical-sensitive field-effect-transistor is made more sensitive to a reducing gas, hydrogen, and less sensitive to oxidizng molecules, like H2S and NO2, by growing a layer of the MOF “ZIF-8” over the nanoparticles. The proposed mechanism is supported by X-ray photoelectron spectroscopy showing that the ZIF-8 membrane partially reduces the PdO sensing layer.

 
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Award ID(s):
1903188
NSF-PAR ID:
10232985
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
The Electrochemical Society
Date Published:
Journal Name:
Journal of The Electrochemical Society
Volume:
167
Issue:
14
ISSN:
0013-4651
Page Range / eLocation ID:
Article No. 147503
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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