Facile synthesis of a novel CAU-17/CSG composite for the trace electrochemical analysis of Zn2+, Cd2+ and Pb2+

Heavy metal ions (HMIs) are accumulative and toxic for the environment, causing one of the recognized social problems, while some metal ions have positive applications in the prognosis of diseases. Therefore, there is a necessity to achieve rapid, convenient, highly efficient determination of HMIs. In this work, a novel composite, CAU-17/CSG, consisting of CAU-17 and cellulose graphene (CSG) is synthesized via in situ growth method and serves as an effective electrochemical sensor. Taking advantages of the high catalytic activity of Bi in CAU-17 and the good synergy between CAU-17 and CSG, CAU-17/CSG exhibits excellent electrocatalytic activity to achieve individual and simultaneous detection of low concentrations of Zn2+, Cd2+ and Pb2+ in aqueous solutions. The limits of detection (LOD) for Zn2+, Cd2+ and Pb2+ are 0.029, 0.008 and 0.011 μM (S/N = 3), with linear ranges of 0.3–10, 0.01–2 and 0.03–2 μM, respectively. Meanwhile, the sensor exhibits good stability, reproducibility and anti-interference ability. As expected, CAU-17/CSG exhibits good accuracy in detecting metal ions in water and blood samples. Considering the simple preparation method, stable structure and excellent performance, the prepared composites will have great potential for environmental and biomedical applications.