Response of Surface Bound Hexacyanoferrate Films to Binary & Tertiary Metal Alloy Compositions

Recently, there has been an increased use of intermittent renewable energy sources. Methods to effectively accommodate various energy storage needs must be explored, as no single system is the best for all applications. Electrochemical capacitors provide a unique platform, as they possess a larger volumetric charge density in comparison to physical capacitors, all while maintaining rapid charging and discharging rates. In particular, Hexacyanoferrate (HCF) films possess a crystal structure which remains physically unaltered during charge cycling, making it an ideal candidate for a durable pseudocapacitor. Transition metals were deposited onto a gold substrate from solution using an electrochemical cell to produce a NiCo or NiCoCu backbone for the thin films. This particular study focuses on variations of the concentrations of the metal ions in solution and the fabrication process which leads samples to exhibiting different properties in charge storage, charge/discharge rates, and qualitative surface characteristics. These films are studied in a scanning electron microscope (SEM) with an energy dispersive x-ray spectroscopy (EDS) attachment to determine their structures and compositions.