Abstract Zinc‐aluminum layered double hydroxide (ZnAl‐LDH) was successfully synthesized via a one‐step coprecipitation method and directly modified onto a glassy carbon electrode (GCE) to construct a ZnAl‐LDH/GCE working electrode. A systematic comparison of MAl‐LDH formed from different divalent metal sources (M = Zn 2+ , Ca 2+ , Mg 2+ , Ni 2+ ) revealed that ZnAl‐LDH exhibited the most favorable morphology and performance. Despite the inherently poor conductivity of LDH materials, the specific interaction between metal hydroxyl groups (−M‐OH) on the ZnAl‐LDH surface and Pb 2+ significantly enhanced the electrochemical response signal for Pb 2+ . Optimization of key parameters including supporting electrolyte, pH, enrichment potential, and time established optimal detection conditions at pH = 5.0 in 0.1 mol/L acetic acid–sodium acetate (ABS) buffer, with enrichment at −0.9 V for 230 s. Under these conditions, the electrochemical sensor demonstrated outstanding analytical performance for Pb 2+ detection: a linear range of 0.4–25 μmol/L, a detection limit as low as 0.031 μmol/L (S/N = 3), along with excellent selectivity, stability, and reproducibility. Satisfactory recovery rates achieved in real‐water samples further validate the sensor's practical application potential in environmental monitoring.
Yang et al. (Wed,) studied this question.