Phosphomolybdate@Carbon-Based Nanocomposites as Electrocatalysts for Oxygen Reduction Reaction

• Type: Article in International Scientific Journal
• Date: 2016

Authors

Nunes, M (Author) FCUP; Diana M Fernandes (Author) FCUP; Rocha, IM (Author) Other; Manuel Fernando R Pereira (Author) FEUP; Mbomekalle, IM (Author) Other; de Oliveira, P (Author) Other; Cristina Freire (Author) FCUP

Journal

Title: ChemistrySelect

Vol. 1

Pages: 6257-6266

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 18 Citations

Scopus - 18 Citations

Other information

Authenticus ID: P-00M-MVB

DOI: 10.1002/slct.201601370

Abstract (EN): Functional materials as electrocatalysts for the oxygen reduction reaction (ORR) are crucial for several renewable energy applications. Herein, we report the application of several nanocomposites, prepared by the incorporation of a vanadium-substituted phosphomolybdate [PMo11VO40](4-) (PMo11V) into some carbon-based materials (carbon black (CBV), single-walled carbon nanotubes (SWCNT) and graphene (GF)), as ORR electrocatalysts. All nanocomposites, denominated as PMo11V@CBV, PMo11V@SWCNT and PMo11V@GF, show electrocatalytic activity for the ORR in acidic medium (pH 2.5 H2SO4/Li2SO4 buffer solution), with a strong dependency between the electrocatalytic ORR performance and the carbon- based material employed. Among the materials studied, the PMo11V@GF nano-composite exhibits the most promising performance, having the less negative onset potential (Eonset=-0.16 V vs. Ag/AgCl (0.18 V vs. RHE)), which is explained by the excellent electronic properties of GF. An ORR process based in a 2-electron mechanism is assumed for all modified electrodes. The PMo(11)Vand the nanocomposite-modified electrodes are also effective for the reduction of hydrogen peroxide, with PMo11V@GF displaying the most promising electrocatalytic performance. The successful preparation of the nanocomposites is confirmed by X-ray photoelectron spectroscopy and Fourier transformed infrared spectroscopy techniques. The electrochemical characterization of all modified electrodes is also reported.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10