MoS₂ Modified Screen Printed Carbon Electrode Based Flexible Electrochemical Sensor for Detection of Copper Ions in Water

Heavy metal ions (HMI), such as Cu
$^{{2}+}$
, are harmful to the environment and our health. Such ions are typically measured using glassy carbon electrode (GCE)-based electrochemical sensors developed on rigid substrates. However, several emerging applications require such sensors on flexible, and even disposable, substrates. Herein, we present a molybdenum disulfide (MoS2)-modified screen-printed carbon electrode (SPCE)-based flexible electrochemical sensor for the detection of copper ions in the water. The sensor exhibits excellent response with a limit of detection (LOD) of
$5.43 \mu \text{M}$
for Cu ions in the range of
$5 \mu \text{M}$
- 5 mM. The developed sensor is compared with MoS2-modified conventional GCE using electrochemical impedance spectroscopy (EIS). The comparative studies show better linearity (
${R}^{{2}}$
value
$\sim $
0.99) for SPCE-based sensor and underline how easily they can detect Cu ions. The interference study, i.e., detection of copper ions in the presence of other HMI-based analytes, also shows the excellent response of SPCE-based flexible electrochemical sensor—thus, demonstrating their practical application is the detection of Cu in water.