The electrodeposition of antimony is first investigated in H2SO4-NH4F-SbF3 solutions. In this study,linear scan voltammetry, cyclic voltammetry, chronoamperometry, chronopotentiometry and SEM-EDXtechniques were utilized. The results suggested that the Sb3+ reduction takes place via a two-step reactionincluding a pre-conversion process. Linear scan voltammetric technique was used to identify theapparent transfer coefficient, exchange current density and apparent activation energy. The numbers oftransfer electrons are calculated to be n1=1 and n2=2. For the first step reaction at 298K, α1 and i01 are0.133 and 3.468×10-3A·cm-2, respectively. The pre-conversion reaction releases two F- ions and doesnot affect NH4+ ions. A series of cyclic voltammograms were recorded at different scan rates and indicatethat the reduction of Sb3+ is an irreversible process that is controlled by diffusion. The diffusioncoefficients of Sb3+ in H2SO4-NH4F-SbF3 electrolyte at different temperatures were calculated to be1.051×10-5 cm2·s-1 (298K), 1.149×10-5 cm2·s-1 (303K), 1.257×10-5 cm2·s-1 (308K), 1.484×10-5 cm2·s-1(313K), and 2.120×10-5 cm2·s-1 (318K). The apparent activation energies of Sb3+ reduction at differentoverpotentials were calculated as 16.932 kJ·mol-1 (-0.230 V), 16.696 kJ·mol-1 (-0.240 V), 16.274 kJ·mol-1 (-0.250 V), 16.195 kJ·mol-1 (-0.260 V), 15.802 kJ·mol-1 (-0.270 V), 15.502 kJ·mol-1 (-0.280 V), 15.244kJ·mol-1 (-0.290 V), 14.964 kJ·mol-1 (-0.300 V), and 14.647 kJ·mol-1 (-0.310 V).
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