title: Electrocatalytic and magnetic properties of ultrathin nanostructured iron-melanin films on Au(111).
abstract: We have prepared ultrathin, nanostructured melanin films on Au(111) by means of electrochemical self-assembly. These films were characterized by using Auger electron spectroscopy, X-ray absorption near-edge structure spectroscopy, scanning tunneling microscopy, magnetic force microscopy, and electrochemical techniques. Two types of nanostructures are present in the film: melanin nanoparticles and Fe(3)O(4) nanoparticles. The melanin nanoparticles contain Fe bonded to oxygen-containing phenolic groups in an octahedral configuration similar to that found in Fe(2)O(3). The inorganic-organic composite exhibits magnetic properties and catalyzes the electroreduction of hydrogen peroxide in alkaline and neutral electrolyte solutions. The electrocatalytic activity depends on the Fe-bound melanin and appears to be similar to that found for Fe-porphyrins.
authors.affiliation: Departamento de Química Física, Facultad de Química, Universidad de La Laguna, 38071 La Laguna, Tenerife, Spain.
authors.forename: Alejandro
authors.initials: A
authors.lastname: González Orive
authors.forename: Patricio
authors.initials: P
authors.lastname: Dip
authors.forename: Yurima
authors.initials: Y
authors.lastname: Gimeno
authors.forename: Pilar
authors.initials: P
authors.lastname: Díaz
authors.forename: Pilar
authors.initials: P
authors.lastname: Carro
authors.forename: Alberto
authors.initials: A
authors.lastname: Hernández Creus
authors.forename: Guillermo
authors.initials: G
authors.lastname: Benítez
authors.forename: Patricia L
authors.initials: PL
authors.lastname: Schilardi
authors.forename: Leandro
authors.initials: L
authors.lastname: Andrini
authors.forename: Felix
authors.initials: F
authors.lastname: Requejo
authors.forename: Roberto C
authors.initials: RC
authors.lastname: Salvarezza
mesh_terms: D002384:Catalysis; D004563:Electrochemistry; D006046:Gold / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry; D007501:Iron / Q000737:chemistry*; D008280:Magnetics; D008543:Melanins / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D046032:Microscopy, Energy-Filtering Transmission Electron; D016252:Microscopy, Scanning Tunneling; D008956:Models, Chemical; D049329:Nanostructures / Q000737:chemistry*; D010084:Oxidation-Reduction; D013057:Spectrum Analysis; D014965:X-Rays
chemical_list: D008543:Melanins; D006046:Gold; D006861:Hydrogen Peroxide; D007501:Iron