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arXiv · 1805.03078

Graphene-Supported Au-Ni Carbon Nitride Electrocatalysts for the ORR in Alkaline Environment

Enrico Negro·Antoine Bach Delpeuch·Keti Vezzu'·Stefano Polizzi·Federico Bertasi·Graeme Nawn·Gioele Pagot·Vito Di Noto
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Abstract

This study reports the preparation and characterization of a new family of electrocatalysts (ECs) for the oxygen reduction reaction (ORR) exhibiting a 'core-shell' morphology. The 'core' consists of graphene sheets, which are covered by a carbon nitride (CN) 'shell' embedding Au and Ni active sites. The investigated ECs are labeled AuNi10-CNl 600/Gr and AuNi10-CNl 900/Gr. The chemical composition and thermal stability are studied by inductively-coupled plasma atomic emission spectroscopy (ICPAES), elemental analysis and by high-resolution thermogravimetric analysis (HR-TGA). The morphology of the ECs is probed by scanning electron microscopy (SEM), highresolution transmission electron microscopy (HR-TEM) and powder X-ray diffraction (XRD). The ORR performance of the ECs is studied both in acid (0.1 M HClO4) and in alkaline medium (0.1 M KOH) by Cyclic Voltammetry with the Thin-Film Rotating Ring-Disk Electrode (CV-TF-RRDE) method. Both ECs exhibit a promising performance in the ORR in the alkaline medium.

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Enrico Negro, Antoine Bach Delpeuch, Keti Vezzu', Stefano Polizzi, Federico Bertasi, Graeme Nawn, Gioele Pagot, Vito Di Noto. 2018-05-08. Graphene-Supported Au-Ni Carbon Nitride Electrocatalysts for the ORR in Alkaline Environment. https://arxiv.org/abs/1805.03078

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