Complex graphene electrode fabrication protocols including conventional chemical vapor deposition and graphene transfer techniques as well as more recent solution‐phase printing and postprint annealing methods have hindered the wide‐scale implementation of electrochemical devices including solid‐state ion‐selective electrodes (ISEs). Herein, a facile graphene ISE fabrication technique that utilizes laser induced graphene (LIG), formed by converting polyimide into graphene by a CO2laser and functionalization with ammonium ion (NH4+) and potassium ion (K+) ion‐selective membranes, is demonstrated. The electrochemical LIG ISEs exhibit a wide sensing range (0.1 × 10−3–150 × 10−3
- Award ID(s):
- 1706343
- NSF-PAR ID:
- 10388665
- Date Published:
- Journal Name:
- Environmental Science: Nano
- Volume:
- 9
- Issue:
- 6
- ISSN:
- 2051-8153
- Page Range / eLocation ID:
- 2149 to 2160
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract m for NH4+and 0.3 × 10−3–150 × 10−3m for K+) with high stability (minimal drop in signal after 3 months of storage) across a wide pH range (3.5–9.0). The LIG ISEs are also able to monitor the concentrations of NH4+and K+in urine samples (29–51% and 17–61% increase for the younger and older patient; respectively, after dehydration induction), which correlate well with conventional hydration status measurements. Hence, these results demonstrate a facile method to perform in‐field ion sensing and are the first steps in creating a protocol for quantifying hydration levels through urine testing in human subjects. -
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d1en00966d
