Synthesis of Triazine Core Schiff Base and its Copper (II), Nickel (II), Zinc (II) and Cobalt (II) Complexes, Potentiometric Sensor Applications

In this thesis, a novel triazine-based Schiff base was synthesized from melamine and 2,4 dihydroxybenzaldehyde, and its Cu(II), Ni(II), Zn(II), and Co(II) complexes were prepared. The synthesized compounds were characterized by Fourier-transform infrared (FT-IR) spectroscopy, confirming coordination through the imine nitrogen and phenolic oxygen atoms. Schiff bases and their metal complexes have been widely employed as ionophores in the development of selective sensors for various species in potentiometric applications. Therefore, in this study, the obtained ligand and its complexes were incorporated as ionophores into polyvinyl chloride (PVC)-based membranes to fabricate potentiometric ion selective electrodes. The performance parameters of the prepared electrodes, including sensitivity, linear response range, detection limit, response time, and selectivity coefficients, were investigated in detail. Notably, the electrode based on the newly synthesized Schiff base exhibited near-Nernstian behavior for Cu(II) ions and demonstrated high selectivity over other ions. The results indicate that triazine-based Schiff bases represent promising ionophore candidates for the development of selective and sensitive potentiometric sensors in analytical chemistry.