Real-time lead ion monitoring for drinking water is in an urgent demand, due to the high biotoxicity of lead. We fabricated a reduced graphene oxide (rGO) percolation network based field-effect transistor (FET) by using an easy and scalable micromolding-in-capillary method for lead ion detection in water. The percolation theory analysis elucidates that the required GO mass concentration for a 2D continuum connection converges at a predictable value. Guided by the theoretical analysis, the prepared rGO network was constructed with 1–4 layers of rGO flakes and exhibits comparable electrical properties with single-layer rGO devices. A thin Al2O3layer was deposited on the device to isolate the analyte from the FET device. With the specific L-Glutathione reduced (GSH) probe, the sensor can reach a limit of detection (LOD) in ppb-level to lead ions. In addition, good selectivity and the high sensing response to Pb2+concentrations around 15 ppb (maximum contaminant level of lead for drinking water, US Environmental Protection Agency) suggest our sensor holds great potential for lead ion monitoring in drinking water.
This content will become publicly available on February 13, 2025
- Award ID(s):
- 2046363
- NSF-PAR ID:
- 10495069
- Editor(s):
- Gilbert C. Walker
- Publisher / Repository:
- ACS publications
- Date Published:
- Journal Name:
- Langmuir
- Volume:
- 40
- Issue:
- 6
- ISSN:
- 0743-7463
- Page Range / eLocation ID:
- 3004 to 3014
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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