New method in synthesis of nano uranyl(VI) Schiff base complexes: Characterization and electrochemical studies

Nano uranyl Schiff base complexes were synthesized by a new method. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images showed nano-particles with sizes between 16 and 30nm. •Some new nano uranyl Schiff base complexes were synthesized.•The complexes are characterized by different techniques.•The electrochemical properties of the uranyl(IV) complexes were investigated by cyclic voltammetry. This study presents a new method in synthesis of nano uranyl Schiff base complexes. In this method slow addition of dilute uranyl(VI) acetate solution to dilute Schiff base solution following the reflux for about 24h, yields nano uranyl(VI) Schiff base complexes. Characterization of Schiff base ligands and nano uranyl complexes has been done using 1H NMR, IR, UV–vis spectroscopy, elemental analysis. Schiff base ligands were synthesized by the condensation of one mole 3,4-diaminobenzophenone and two moles salicylaldehyde or substituted salicylaldehyde (3-OMe, 4-OMe, 5-OMe, 5-Br, 5-Cl). The electrochemical properties of the uranyl(IV) complexes were investigated by cyclic voltammetry. A good correlation was observed between the oxidation potentials and the electron withdrawing character of the substituents on the Schiff base ligands, according to the following trend: 5-MeO