Synergistic effects of additives on morphology, texture and discharge mechanism of zinc during electrodeposition

The effect of different combination of additives, cetyltrimethylammonium bromide (CTAB), salicylaldehyde (SAL) and acetic acid (AA) on surface morphology, texture and grain size of zinc electrodeposits were systematically analyzed by scanning electron microscopy (SEM) and X-ray diffraction pattern (XRD). Results show that, the co-existence of all three additives in plating bath generates uniform, compact and bright zinc deposit. The voltammetric studies reveal the combined interaction of additives on plating surface during electrodeposition. This interaction leads to synergistic effect on smoothening the deposit surface, refining the grain size and development of the preferred orientation of the deposit. Also influence of additives on nucleation and growth mechanisms of zinc at glassy carbon electrode were investigated by chronoamperometric studies.

► The co-existence of additives generates smooth, bright zinc electrodeposit.
► The presence of individual additives gave unsatisfactory coatings.
► Additives interact synergistically and increases nucleation density.