Work

A Durable Graphitic-Carbon Support for Pt and Pt3Co Cathode Catalysts in Polymer Electrolyte Fuel Cells

Year: 2012

Type: article

Abstract: The high efficiency of fuel-cell-powered electric vehicles makes them a potentially viable option for future transportation. Polymer Electrolyte Fuel Cells (PEFCs) are most promising among various fuel cells for electric traction due to their quick start-up and low-temperature operation. In recent years, the performance of PEFCs has reached the acceptable level both for automotive and stationary applications and efforts are now being expended in increasing their durability, which remains a major concern in their commercialization. To make PEFCs meet automotive targets an understanding of the factors affecting the stability of carbon support and platinum catalyst is critical. Alloying platinum (Pt) with first-row transition metals such as cobalt (Co) is reported to facilitate both higher degree of crystallinity and enhanced activity in relation to pristine Pt. But a major challenge for the application of Pt-transition metal alloys in PEFCs is to improve the stability of these binary catalysts. Dissolution of the non-precious metal in the acidic environment could alleviate the activity of the catalysts and hence cell performance. The use of graphitic carbon as cathode-catalyst support enhances the long-term stability of Pt and its alloys in relation to non-graphitic carbon as the former exhibits higher resistance to carbon corrosion in relation to the latter in PEFC cathodes during accelerated-stress test (AST). Changes in electrochemical surface area (ESA), cell performance and charge-transfer resistance are monitored during AST through cyclic voltammetry, cell polarization and impedance measurements, respectively. Studies on catalytic electrodes with X-ray diffraction, Raman spectroscopy and transmission electron microscopy reflect that graphitic carbon-support resists carbon corrosion and helps mitigating aggregation of Pt and Pt 3 Co catalyst particles.

Source: Journal of The Electrochemical Society

DOI: 10.1149/2.051301jes

Authors: S. Vinod Selvaganesh, P. Sridhar, S. Pitchumani, A. K. Shukla

Institutions: Central Electrochemical Research Institute, Council of Scientific and Industrial Research, Indian Institute of Science Bangalore

Language: English

Topic: Fuel Cells and Related Materials

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: bronze

Funders: Neurosurgery Research and Education Foundation, Ministry of New and Renewable Energy India, Central ElectroChemical Research Institute