title: Platinum electrodeposition at unsupported electrochemically reduced nanographene oxide for enhanced ammonia oxidation.
abstract: The electrochemical reduction of highly oxidized unsupported graphene oxide nanosheets and its platinum electrodeposition was done by the rotating disk slurry electrode technique. Avoiding the use of a solid electrode, graphene oxide was electrochemically reduced in a slurry solution with a scalable process without the use of a reducing agent. Graphene oxide nanosheets were synthesized from carbon platelet nanofibers to obtain highly hydrophilic layers of less than 250 nm in width. The graphene oxide and electrochemically reduced graphene oxide/Pt (erGOx/Pt) hybrid materials were characterized through different spectroscopy and microscopy techniques. Pt nanoparticles with 100 facets, clusters, and atoms at erGOx were identified by high resolution transmission electron microscopy (HRTEM). Cyclic voltammetry was used to characterize the electrocatalytic activity of the highly dispersed erGOx/Pt hybrid material toward the oxidation of ammonia, which showed a 5-fold current density increase when compared with commercially available Vulcan/Pt 20%. This is in agreement with having Pt (100) facets present in the HRTEM images of the erGOx/Pt material.
authors.affiliation: Department of Chemistry and Center for Advanced Nanoscale Materials, University of Puerto Rico, Río Piedras Campus , P.O. Box 23346, San Juan, Puerto Rico 00931-3346, United States.
authors.forename: Lisandro
authors.initials: L
authors.lastname: Cunci
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Velez
authors.forename: Ivan
authors.initials: I
authors.lastname: Perez
authors.forename: Amal
authors.initials: A
authors.lastname: Suleiman
authors.forename: Eduardo
authors.initials: E
authors.lastname: Larios
authors.forename: Miguel
authors.initials: M
authors.lastname: José-Yacamán
authors.forename: James J
authors.initials: JJ
authors.lastname: Watkins
authors.forename: Carlos R
authors.initials: CR
authors.lastname: Cabrera
mesh_terms: D000641:Ammonia / Q000737:chemistry*; D004566:Electrodes; D004595:Electroplating / Q000379:methods*; D005583:Fourier Analysis; D006108:Graphite / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry*; D056951:Photoelectron Spectroscopy; D010984:Platinum / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D013818:Thermogravimetry; D014961:X-Ray Diffraction
chemical_list: D010087:Oxides; D010984:Platinum; D000641:Ammonia; D006108:Graphite