A Compositional Analysis of Electrodeposited Bismuth-Lead Oxides

This thesis describes a study of the composition of bismuth-lead oxide films that have been electrodeposited from acidic and alkaline tartrate solutions. Inductively Coupled Plasma (ICP) spectrometry was used to determine the bulk composition of the dissolved films as well as the current efficiency for the deposition process. Film compositions varied with the applied potential at which they were deposited for bismuth-lead oxide (Bi-Pb-O) films from alkaline tartrate solutions. The Bi-Pb-O films from the alkaline tartrate solution were deposited on stainless steel disks at potentials ranging from 1.0V to 1.6V versus Bi rod at 65°C and room temperature under stirred and unstirred conditions. The resulting films were amorphous by X-ray diffraction. The Faradaic current efficiency for the deposition process, based upon ICP analyses of dissolved films ranged from a low of 1% at room temperature to a high 44% stirred at 65°C. Attempts to grow Bi-Pb-O films of varying compositions from acidic solutions resulted in the bismuth-lead compositions that approximated the solution composition of bismuth and lead. Faradaic current efficiencies, based upon ICP analysis of the dissolved Bi-Pb-O films from acidic solutions ranged from a low 2% stirred at room temperature to a high 50% at room temperature, and are strongly influenced by Bi/Pb ratio of the solution