Polybetaine stabilized platinum nanoparticles, method for the production thereof and utilization for fuel-cell catalysts

US6391818B1 · kind B1 · utility

Assignee

• Celanese Ventures GmbH · DE

Inventors

• Harald Bönsel · Niedernhausen, DE
• Gregor Deckers · Frankfurt, DE
• Georg Frank · Nürnberg, DE
• Hans Millauer · Eschborn, DE
• Thomas Soczka-Guth · Schelklingen, DE

Key dates

• Filing date: Aug 31, 2000
• Grant date: May 21, 2002
• Expiry date: Aug 31, 2020

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02E60/50
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

Polybetaine-stabilized nanosize platinum particles, a process for preparing them and their use for electrocatalysts in fuel cellsSoluble nanosize particles which have a diameter of from 0.5 to 3 nm, preferably from 1 to 2 nm, comprise platinum alone or platinum and other metals of the platinum group and are embedded in a protective colloid which comprises polymeric betaines and can be degraded by hydrolysis. The betaine is preferably a carbobetaine of the formula —N+R1R2—(—CH2—)n—CO2−, a phosphobetaine of the formula —N+R1R2—(—CH2—)n—PO3— or, preferably, a sulfobetaine of the formula —N+R1R2—(—CH2—)n—SO3—, where R1 and R2 may, independently of one another, be identical or different and are alkyl radicals having from 1 to 6 carbon atoms and n is 1, 2 or 3. Also described are a process for preparing the nanosize particles and catalysts produced therefrom and also their use for fuel cells.