Hollow platinum nanoparticles for fuel cells
AssigneesL'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude, Institut Polytechnique De Grenoble, Centre National De La Recherche Scientifique
InventorsAudrey Montaut, Sandrine Moutin, Marian Julien Chatenet, Julien Frederic Christophe Durst, Frederic Thibaut Maillard, Laetitia Dubau
Life of this patent
Estimating the term…
Abstract
The present invention relates to hollow platinum nanoparticles with a diameter comprised between 3 and 20 nm which comprise a first central cavity and optionally at least one second cavity at the periphery of the first cavity, the shell of which is dense and single-crystal with a thickness comprised between 0.2 and 5 nm. The invention also relates to a method for manufacturing such nanoparticles, as well as to their use as an electrocatalyst in fuel cells.
Claims9
A method for manufacturing hollow platinum nanoparticles comprising a dense and single-crystal shell having a thickness of from 0.2 nm to 5 nm and a first central cavity and optionally at least one second cavity at a periphery of the first central cavity, wherein the nanoparticle has a diameter in a range of from 3 nm to 20 nm, is quasi-spherical in shape, and does not comprise a non-noble metal alloy element, the method comprising the following steps:
- a) placing PtxM/C nanoparticles into a polarization device, where:
- Pt is platinum;
- x is in a range of from 0.2 to 10;
- M is a metal less noble than platinum;
- C is carbon;
- and
- Pt and M are supported on the carbon;
- b) subjecting the nanoparticles for a plurality of times to a sequence of polarizations between the two following potentials:
- a reducing potential of from 0 to 0.5 volts relative to a reversible hydrogen electrode (V/RHE), and
- an oxidizing potential of from 0.6 to 1.4 V/RHE, until single-crystal hollow platinum nanoparticles are obtained having a diameter of from 3 nm to 20 nm and a dense shell having a thickness of from 0.2 nm to 5 nm,
- wherein the polarization device is a rotary conducting drum, and the step b) is carried out in an electrolytic solution.
Dependencies are inferred from the claim text.