High
concentration of dissolved phosphate ions is the main responsible
factor for eutrophication of natural water bodies. Therefore, detection
of phosphate ions is essential for evaluating water eutrophication.
There is a need at large-scale production of real-time monitoring
technology to detect phosphorus accurately. In this study, facile
enzymeless phosphate ion detection is reported using a nozzle-jet-printed
silver/reduced graphene oxide (Ag/rGO) composite-based field-effect
transistor sensor on flexible and disposable polymer substrates. The
sensor exhibits promising results in low concentration as well as
real-time phosphate ion detection. The sensor shows excellent performance
with a wide linear range of 0.005–6.00 mM, high sensitivity
of 62.2 μA/cm
2
/mM, and low detection limit of 0.2
μM. This facile combined technology readily facilitates the
phosphate ion detection with high performance, long-term stability,
excellent reproducibility, and good selectivity in the presence of
other interfering anions. The sensor fabrication method and phosphate
detection technique yield low-cost, user-friendly sensing devices
with less analyte consumption, which are easy to fabricate on polymer
substrates on a large scale. Besides, the sensor has the capability
to sense phosphate ions in real water samples, which makes it applicable
in environmental monitoring.