Insights in the Study of the Oxygen Reduction Reaction in Direct Ethanol Fuel Cells using Hybrid Platinum‐Ceria Nanorods Electrocatalysts

Abstract

This work reports on the synthesis and characterization of hybrid electrocatalysts based on Pt nanoparticles and ceria nanorods (CeO 2 NR) supported on Vulcan XC-72 carbon black (Pt x (CeO 2 NR) y C z ) and evaluation of their electrocatalytic activity towards the oxygen reduction reaction (ORR), aiming the application of 4-electrons process in direct ethanol fuel cells (DEFCs). The hybrid electrocatalysts are characterized by X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), transmission electron microscopy (TEM), contact angle measurements and X-ray photoelectron spectroscopy (XPS), inductively coupled plasma mass spectrometry (ICP-MS), CO-stripping analysis and electrocatalytic activity for ORR studied by the rotating ring-disc electrode (RRDE) technique and single fuel cell experiments. The Pt x (CeO 2 NR) y C z hybrid electrocatalysts prove to be efficient for ORR in a 4-electron process, maintaining a high conversion rate of O 2 to H 2 O, even at reduced platinum (Pt) load. The electrocatalyst presents a notable an unusual behavior in single fuel cell experiments presenting slightly lower open circuit voltage than Pt based commercial electrocatalysts, containing Pt only, as well as improved current and power density. This is achieved at operating temperatures between 40°C and 70°C, making the material very promising for application in high efficiency low temperature fuel cells.[a] V.

Noncovalent interactions on the electrocatalytic oxidation of ethanol on a Pt/C electrocatalyst

“…Figure shows the TEM image of the Pt/C electrocatalyst, which reveals that Pt nanoparticles (NPs) are uniformly dispersed and the average particle size is about 7.9 nm. The crystalline structures of Pt NPs were examined using high‐resolution transmission electron microscopy (HRTEM), and lattice fringes with distances of 0.23, 0.20, 0.14, and 0.12 nm, corresponding to the (111), 27 (200), 28 (220), 29 and (311) 29 planes, respectively, were observed and are shown in Figure .…”

A Review on Ceo2‐Based Electrocatalyst and Photocatalyst in Energy Conversion

“…Pinheiro et al reported a hybrid electrocatalyst constructed by Pt nanoparticles and CeO 2 nanorods supported on carbon black for ORR with the aim of application in fuel cells. [ 70 ] As a result, the electrocatalyst shows an improved current and power density than the commercial Pt‐based electrocatalysts. Li et al obtained a similar result and attribute the enhanced performance to that the interaction between CeO 2 and Pt nanoparticles, which prevents surface Pt nanoparticles from aggregation.…”