Selective and efficient solid phase extraction of cadmium (II) in sub-trace limits based on alizarin red-S cross-linked-2-mercapto-N-(3-(triethoxysilyl) propyl) acetamide bi-functionalized graphene oxide nanocomposite from different environmental water samples

Abstract

A novel bi-functionalized nanocomposite based on graphene oxide-alizarin red-S cross-linked-2-mercapto-N-(3-(triethoxysilyl) propyl) acetamide (ARS-MTPS@GO) was developed for the sequestration of cadmium Cd(II) ions from water. The nanocomposite fabrication was characterized through different physicochemical techniques (FTIR, XRD, SEM, TEM, Raman, and TGA). In addition to its hydrophilicity, high surface area, and ability to interact with the functionalized moieties, the ARS-MTPS@GO nanocomposite has improved Cd(II) adsorption. An optimization study was carried out on various analytical parameters that affect cadmium extraction, including the pH, contact time, and nanocomposite mass dosage. The maximum sorption capacity and percentage removal efficiency of Cd(II) ions reached 222.7 mg g−1 and 99.4 ± 3.7%, respectively, at pH = 6 within 30 minutes and the pseudo-second-order kinetic model best fits the sorption rate. Validation of the proposed method was evaluated for nine replicate measurements for recovery of Cd(II), showed favorable analysis precision, and the estimated detection limit was 0.18 ± 0.02 ng mL−1. Additionally, the reusability and stability of the nanocomposite and the effects of interfering cations and anions were investigated. Finally, the developed method was successfully applied for the selective extraction of Cd(II) from environmental water samples of different matrices, and the Cd(II) recoveries were 96.2–99.2%±2.3%. This study’s findings prove the potential applicability of the novel nanocomposite for removing cadmium ions from different environmental waters.