Two new Cu(II) Schiff base complexes, [Cu(L)2](ClO4)2 (1) and [Cu(L)2NO3]NO3 (2) of Schiff base ligand (L = 4,5,9,13,14-pentaaza-benzo[b] triphenylen) were synthesized and characterized by elemental analyses (CHN), FT-IR, Uv–Vis and conductivity measurements. Nano-structure compounds of the complex (1) were prepared by sonochemical (3) and solvothermal (4) methods. The new nano-structures were characterized by scanning electron microscopy, X-ray powder diffraction, IR spectroscopy and elemental analyses. The thermal stability of bulk complexes and nano-sized particles (3 and 4) were studied by thermal gravimetric (TGA) and differential scanning calorimetry (DSC) analyses. CuO nano-particles were obtained by calcination of the nano-structure complexes at 450 ºC. The comparative electrochemical studies show that the copper complexes give quasi-reversible reduction process in CH3CN solution. The free Schiff base and its metal complexes have been screened for antibacterial activities and the result show that the metal complexes are more active than its free Schiff base ligand