Next Article in Journal
A DFT Study on the Adsorption of H2S and SO2 on Ni Doped MoS2 Monolayer
Next Article in Special Issue
Nano-MnO2 Decoration of TiO2 Microparticles to Promote Gaseous Ethanol Visible Photoremoval
Previous Article in Journal
Micropatterning of Metal Nanoparticle Ink by Laser-Induced Thermocapillary Flow
Previous Article in Special Issue
Band Gap Implications on Nano-TiO2 Surface Modification with Ascorbic Acid for Visible Light-Active Polypropylene Coated Photocatalyst
Article Menu
Issue 9 (September) cover image

Export Article

Open AccessArticle

Synergistic Effects of Active Sites’ Nature and Hydrophilicity on the Oxygen Reduction Reaction Activity of Pt-Free Catalysts

1
Dipartimento di Chimica, Università degli Studi di Milano, Via Golgi 19, 20133 Milano, Italy
2
ESRF—The European Synchrotron, 71, Avenue des Martyrs, 38043 Grenoble, France
3
Dipartimento di Ingegneria Civile, dell’Energia, dell’Ambiente e dei Materiali, Università “Mediterranea”, Via Graziella, Loc. Feo di Vito, 89122 Reggio Calabria, Italy
4
Dipartimento di Scienze Matematiche e Informatiche, Scienze Fisiche e Scienze della Terra, Università di Messina, Viale Stagno d’Alcontres 31, 98166 Messina, Italy
5
Dipartimento di Chimica, Università degli Studi di Bari Aldo Moro, Via Orabona 4, 70125 Bari, Italy
6
Dipartimento di Energia and NEMAS—Centre for NanoEngineered MAterials and Surfaces, Politecnico di Milano, Via Ponzio 34/3, 20133 Milano, Italy
*
Author to whom correspondence should be addressed.
Nanomaterials 2018, 8(9), 643; https://doi.org/10.3390/nano8090643
Received: 27 July 2018 / Revised: 11 August 2018 / Accepted: 21 August 2018 / Published: 22 August 2018
  |  
PDF [3936 KB, uploaded 11 September 2018]
  |  

Abstract

This work highlights the importance of the hydrophilicity of a catalyst’s active sites on an oxygen reduction reaction (ORR) through an electrochemical and physico-chemical study on catalysts based on nitrogen-modified carbon doped with different metals (Fe, Cu, and a mixture of them). BET, X-ray Powder Diffraction (XRPD), micro-Raman, X-ray Photoelectron Spectroscopy (XPS), Scanning Electron Microscopy (SEM), Scanning Transmission Electron Microscopy (STEM), and hydrophilicity measurements were performed. All synthesized catalysts are characterized not only by a porous structure, with the porosity distribution centered in the mesoporosity range, but also by the presence of carbon nanostructures. In iron-doped materials, these nanostructures are bamboo-like structures typical of nitrogen carbon nanotubes, which are better organized, in a larger amount, and longer than those in the copper-doped material. Electrochemical ORR results highlight that the presence of iron and nitrogen carbon nanotubes is beneficial to the electroactivity of these materials, but also that the hydrophilicity of the active site is an important parameter affecting electrocatalytic properties. The most active material contains a mixture of Fe and Cu. View Full-Text
Keywords: oxygen reduction reaction; Pt-free catalysts; CNT N-doped carbons; active site hydrophilicity oxygen reduction reaction; Pt-free catalysts; CNT N-doped carbons; active site hydrophilicity
Figures

Graphical abstract

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Supplementary material

SciFeed

Share & Cite This Article

MDPI and ACS Style

Longhi, M.; Cova, C.; Pargoletti, E.; Coduri, M.; Santangelo, S.; Patanè, S.; Ditaranto, N.; Cioffi, N.; Facibeni, A.; Scavini, M. Synergistic Effects of Active Sites’ Nature and Hydrophilicity on the Oxygen Reduction Reaction Activity of Pt-Free Catalysts. Nanomaterials 2018, 8, 643.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Nanomaterials EISSN 2079-4991 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top