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Title: Cylindrical C 96 Fullertubes: A Highly Active Metal‐Free O 2 ‐Reduction Electrocatalyst
Abstract

A new isolation protocol was recently reported for highly purified metallic FullertubesD5h‐C90,D3d‐C96, andD5d‐C100,which exhibit unique electronic features. Here, we report the oxygen reduction electrocatalytic behavior of C60, C70(spheroidal fullerenes), and C90, C96, and C100(tubular fullerenes) using a combination of experimental and theoretical approaches. C96(a metal‐free catalyst) displayed remarkable oxygen reduction reaction (ORR) activity, with an onset potential of 0.85 V and a halfway potential of 0.75 V, which are close to the state‐of‐the‐art Pt/C benchmark catalyst values. We achieved an excellent power density of 0.75 W cm−2using C96as a modified cathode in a proton‐exchange membrane fuel cell, comparable to other recently reported efficient metal‐free catalysts. Combined band structure (experimentally calculated) and free‐energy (DFT) investigations show that both favorable energy‐level alignment active catalytic sites on the carbon cage are responsible for the superior activity of C96.

 
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Award ID(s):
1856461
NSF-PAR ID:
10369513
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
61
Issue:
21
ISSN:
1433-7851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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