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

Heavy metal ions (HMI), such as Cu2+, 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 M for Cu ions in the range of 5 mu 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 similar to 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.