Controlling the Active Sites of Sulfur-Doped Carbon Nanotube-Graphene Nanolobes for Highly Efficient Oxygen Evolution and Reduction Catalysis
- Univ. of Connecticut, Storrs, CT (United States). Dept. of Chemistry and Inst. of Materials Science; Tanta Univ. (Egypt). Dept. of Chemistry
- Univ. of Connecticut, Storrs, CT (United States). Dept. of Chemistry; Tanta Univ. (Egypt). Dept. of Chemistry
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton NY 11973 USA; Brookhaven National Lab. (BNL), Upton, NY (United States). Center for Functional Nanomaterials
- Univ. of Connecticut, Storrs, CT (United States). Dept. of Chemistry
- Photon Science Directorate, Brookhaven National Laboratory, Upton NY 11973 USA; Brookhaven National Lab. (BNL), Upton, NY (United States)
- Univ. of Connecticut, Storrs, CT (United States). Dept. of Chemistry and Inst. of Materials Science
- Univ. of Connecticut, Storrs, CT (United States). Dept. of Chemistry and Inst. of Materials Science and Chemical and Biomolecular Engineering
Controlling active sites of metal-free catalysts is an important strategy to enhance activity of the oxygen evolution reaction (OER). We made many attempts have been made to develop metal-free catalysts, but the lack of understanding of active-sites at the atomic-level has slowed the design of highly active and stable metal-free catalysts. We also developed a sequential two-step strategy to dope sulfur into carbon nanotube–graphene nanolobes. This bidoping strategy introduces stable sulfur–carbon active-sites. Fluorescence emission of the sulfur K-edge by X-ray absorption near edge spectroscopy (XANES) and scanning transmission electron microscopy electron energy loss spectroscopy (STEM-EELS) mapping and spectra confirm that increasing the incorporation of heterocyclic sulfur into the carbon ring of CNTs not only enhances OER activity with an overpotential of 350 mV at a current density of 10 mA cm-2, but also retains 100% of stability after 75 h. Furthermore, the bidoped sulfur carbon nanotube–graphene nanolobes behave like the state-of-the-art catalysts for OER but outperform those systems in terms of turnover frequency (TOF) which is two orders of magnitude greater than (20% Ir/C) at 400 mV overpotential with very high mass activity 1000 mA cm-2 at 570 mV. Moreover, the sulfur bidoping strategy shows high catalytic activity for the oxygen reduction reaction (ORR). Stable bifunctional (ORR and OER) catalysts are low cost, and light-weight bidoped sulfur carbon nanotubes are potential candidates for next-generation metal-free regenerative fuel cells.
- Research Organization:
- Brookhaven National Lab. (BNL), Upton, NY (United States). Center for Functional Nanomaterials (CFN)
- Sponsoring Organization:
- USDOE Office of Science (SC), Basic Energy Sciences (BES)
- Grant/Contract Number:
- SC00112704; FG02-86ER13622.A000
- OSTI ID:
- 1336156
- Report Number(s):
- BNL-112670-2016-JA; KC0403020
- Journal Information:
- Advanced Energy Materials, Vol. 6, Issue 5; ISSN 1614-6832
- Publisher:
- WileyCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
Similar Records
Sulphur modulated Ni3FeN supported on N/S co-doped graphene boosts rechargeable/flexible Zn-air battery performance
Interfacial Engineering of W 2 N/WC Heterostructures Derived from Solid‐State Synthesis: A Highly Efficient Trifunctional Electrocatalyst for ORR, OER, and HER