Application of graphene/zinc-based metal-organic framework nanocomposite for electrochemical sensing of As(III) in water resources

• Published in: Analytica chimica acta 2020-02, Vol.1099, p.60-67
• Main Authors: Baghayeri, Mehdi, Ghanei-Motlagh, Masoud, Tayebee, Reza, Fayazi, Maryam, Narenji, Fatemeh
• Format: Article
• Language: English
• Subjects: Arsenic; Modified electrode; Stripping voltammetry; Water samples
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2019.11.045

In this study, a novel nanocomposite of graphene oxide/zinc based metal-organic framework (GO/MOF) was prepared through a simple solvothermal method. The electrochemical As(III) sensing capability of the nanocomposite was explored by casting the GO/MOF on a glassy carbon electrode (GCE), followed by an electrochemically reduction of GO. As(III) detection was performed by the differential pulse anodic stripping voltammetry (DPASV) method after closed-circuit mode. The present sensor showed excellent electrochemical performance such as a wide linear range from 0.2 to 25 ppb (μg/L), low detection limit (S/N = 3) of 0.06 ppb and good reproducibility with a relative standard deviation (RSD) value of 2.1%. The detection limit of As(III) is lower than the threshold value set by the Environmental Protection Agency (EPA) in drinking water. A good selectivity for As(III) detection by the proposed Gr/MOF-GCE was also demonstrated. Finally, this platform was employed for the As(III) monitoring in environmental water samples, and the accuracy of obtained results were confirmed by inductively coupled plasma-optical emission spectrometer (ICP-OES) system. [Display omitted] •Gr/MOF-based electrochemical sensor was sensitive for the determination of As(III) due to synergistic effect.•Detection limit of sensor for As(III) detection was 0.06 ppb.•The interference from some heavy metal ions was found negligible for As(III) analysis.•As(III) was detected effectively in environmental water samples.