Ultralow-loading platinum-cobalt fuel cell catalysts derived from imidazolate frameworks.
- Resource Type
- Article
- Authors
- Chong, Lina; Wen, Jianguo; Kubal, Joseph; Sen, Fatih G.; Zou, Jianxin; Greeley, Jeffery; Chan, Maria; Barkholtz, Heather; Ding, Wenjiang; Liu, Di-Jia
- Source
- Science. 12/14/2018, Vol. 362 Issue 6420, p1276-1281. 6p. 4 Diagrams.
- Subject
- *FUEL cells
*CATALYTIC activity
*ELECTROCATALYSTS
*OXIDATION-reduction reaction
*PLATINUM
*COBALT
- Language
- ISSN
- 0036-8075
Achieving high catalytic performance with the lowest possible amount of platinum is critical for fuel cell cost reduction. Here we describe a method of preparing highly active yet stable electrocatalysts containing ultralow-loading platinum content by using cobalt or bimetallic cobalt and zinc zeolitic imidazolate frameworks as precursors. Synergistic catalysis between strained platinum-cobalt core-shell nanoparticles over a platinum-group metal (PGM)–free catalytic substrate led to excellent fuel cell performance under 1 atmosphere of O2 or air at both high-voltage and high-current domains. Two catalysts achieved oxygen reduction reaction (ORR) mass activities of 1.08 amperes per milligram of platinum (A mgPt−1) and 1.77 A mgPt−1 and retained 64% and 15% of initial values after 30,000 voltage cycles in a fuel cell. Computational modeling reveals that the interaction between platinum-cobalt nanoparticles and PGM-free sites improves ORR activity and durability. [ABSTRACT FROM AUTHOR]