Synergistic effects of benzalacetone and benzophenone on the electrocrystallization of tin from acid stannous sulphate solutions

• Published in: Journal of applied electrochemistry 1994-05, Vol.24 (5), p.404-410
• Main Authors: NAKAMURA, Y, KANEKO, N, NAKAMURA, M, NEZU, H
• Format: Article
• Language: English
• Subjects: Chemistry; Electrochemistry; Exact sciences and technology; General and physical chemistry; Miscellaneous (electroosmosis, electrophoresis, electrochromism, electrocrystallization, ...)
• ISSN: 0021-891X; 1572-8838
• DOI: 10.1007/BF00254152

The synergistic effects of two kinds of aromatic ketones (benzalacetone (BA), benzophenone (BP)) and N,N-bis(polyoxyethylene)octadecylamines (POOA) on the surface morphology and the crystal orientation of electrodeposited Sn from acid stannous sulphate solutions have been studied by electrochemical methods, scanning electron microscopy and x-ray diffractometry. BA itself had no effect on the reduction of Sn(II) ions, but the reduction product of BA had a strong inhibitory effect on the reduction of Sn(II) ions. However, the inhibitory effect of BP was stronger than that of the reduction product of BP. POOA induced a uniform deposition of Sn over the whole surface, but the crystal grain size and the surface roughness of electrodeposited Sn were relatively large. On the other hand, fine-grained and smooth electrodeposited Sn, which had a preferred orientation with the [100] plane parallel to the surface, were obtained from acid stannous sulphate solutions containing POOA, BA and BP due to the synergistic effects of the three kinds of adsorbed species. It was found that BA has a levelling action and BP has a grain refinement action.