EFFECT OF COMPLEXING AGENT (CITRIC-ACID) AND PH ON THE CATHODIC DEPOSITION OF AS-SB ALLOYS

As-Sb alloys have been cathodically deposited onto nickel electrodes f rom acidic aqueous solutions containing citric acid. The effect of com plexing agent concentration, pH, angular speed of the RDE and temperat ure on deposition rate and alloy composition have been monitored. Incr easing citric acid concentration and pH decrease the deposition curren t and the antimony content of the alloys (measured by EDX analyses). T he opposite effect is observed when rotation speed or temperature are increased. Under most combinations of citric acid concentration and pH , the steady-state i/E curves show the current peak already observed i n a previous investigation. The morphology and structure of the alloys have been studied with scanning electron microscopy and X-ray diffrac tion. Alloys containing greater-than-or-equal-to 74% Sb were found to be crystalline (hexagonal system).