title: Surface modification of neural stimulating/recording electrodes with high surface area platinum-iridium alloy coatings.
abstract: High-surface area platinum-iridium alloys were electrodeposited by on Pt and Au microelectrodes using a potential sweep technique. Detailed investigations of the structure and morphology and the electrochemical properties of the electrodeposited Pt-Ir alloy coatings were performed. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were used for the determination of the surface morphology and the chemical composition of the Pt-Ir coatings, respectively. The elemental analysis by EDS showed a nearly 60-40% Pt-Ir composition of the coatings. The electrochemical properties of the Pt-Ir coatings were evaluated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). CV and EIS measurements revealed that the Pt-Ir coated electrodes exhibit significantly increased charge storage capacity and real surface area compared to uncoated Pt electrodes. Charge injection experiments of the Pt-Ir coated microelectrodes revealed low potential excursions, indicating high charge injection capabilities within safe potential limits.
authors.affiliation: Chemical Engineering and Materials Science Department, University of Southern California, Los Angeles, CA 90089, USA. apetross@usc.edu
authors.forename: Artin
authors.initials: A
authors.lastname: Petrossians
authors.forename: John J
authors.initials: JJ
authors.lastname: Whalen
authors.forename: James D
authors.initials: JD
authors.lastname: Weiland
authors.forename: Florian
authors.initials: F
authors.lastname: Mansfeld
mesh_terms: D000497:Alloys; D004566:Electrodes; D007495:Iridium / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D010984:Platinum / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D000497:Alloys; D007495:Iridium; D010984:Platinum