Polypyrrole functionalized MoS₂ for sensitive and simultaneous determination of heavy metal ions in water

Assessing heavy metal ion (HMI) contamination to sustain drinking water hygiene is a challenge. Conventional approaches are appealing for the detection of HMIs but electrochemical approaches can resolve the limitations of these approaches, such as tedious sample preparation, high cost, time consuming and the need for trained professionals. Here, an electrochemical approach is developed using a nano-sphered polypyrrole (PPy) functionalized with MoS₂ (PPy/MoS₂) by square wave anodic stripping voltammetry for the detection of HMIs. The developed sensor can detect Pb²⁺ with a limit of detection of 0.03 nM and a sensitivity of 36.42 μA nM^-1. Additionally, the PPy/MoS₂ sensor was employed for the simultaneous detection of HMIs of Cd²⁺, Pb²⁺, Cu²⁺ and Hg²⁺. The reproducibility, stability and anti-interference studies confirm that the sensor can be used to monitor HMI contamination of water.