Cylindrical C 96 Fullertubes: A Highly Active Metal-Free O 2 -Reduction Electrocatalyst

• Published in: Angewandte Chemie (International ed.) Vol. 61; no. 21; p. e202116727
• Main Authors: Sanad, Mohamed Fathi, Franklin, Hannah M, Ali, Basant A, Puente Santiago, Alain R, Nair, Aruna N, Chava, Venkata S N, Fernandez-Delgado, Olivia, Allam, Nageh K, Stevenson, Steven, Sreenivasan, Sreeprasad T, Echegoyen, Luis
• Format: Journal Article
• Language: English
• Published: Germany Wiley Blackwell (John Wiley & Sons) 16.05.2022
• Subjects: Fullerenes; Oxygen Reduction Reaction; C96; Electrocatalysis; Molecular Catalysis; Band Alignment
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.202116727

A new isolation protocol was recently reported for highly purified metallic Fullertubes D -C , D -C , and D -C which exhibit unique electronic features. Here, we report the oxygen reduction electrocatalytic behavior of C , C (spheroidal fullerenes), and C , C , and C (tubular fullerenes) using a combination of experimental and theoretical approaches. C (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 using C as 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 C .