Tailored porous triazine-based organic frameworks decorated with gold nanoparticles: A robust platform for ultra-sensitive arsenite detection

An effective electrochemical sensing platform for As(III) determination was developed through in situ growing gold nanoparticles electrocatalyst inside the highly microporous melamine-based chemical organic framework (N-POP) with a large surface area prepared through the catalyst-free polycondensation between melamine and terephthalaldehyde. The microporous structure afforded support for the synchronous anchoring of more gold nanoparticles and exposing abundant unsaturated active sites for highly sensitive As(III) detection. The optimized synthesis was characterized by FT-IR, SEM, HR-TEM, UV-Vis, and XPS successful formation of the polymer, and the morphologically favorable heterojunction between AuNPs and the N-POP gave rise to enhanced electrochemical responses toward As(III) determination. Several parameters related to the synthesis of the nanocomposite and instrumental parameters were optimized to achieve the best performance of the sensor. Under optimized conditions, the electrode exhibits enhanced electrochemical performance toward As(III) without noticeable interference from other commonly coexisting ions on the determination of As(III). Additionally, robust stability and reproducibility were achieved for the electrodes. While this work forms the basis for further progress on nanomaterials-coated COFs, As(III) detection in different water samples was successfully demonstrated here.