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Abstract Nitrogen‐doped graphitic carbon materials have been widely used as a catalyst support in the methanol oxidation reaction (MOR). In this study, we report the role of three‐dimensionally architectured in‐situ N‐doped vertically aligned carbon nanofibers (VACNF) as a catalyst support for MOR in acidic and alkaline media. The abundant graphitic edge sites at the sidewall of N‐doped VACNF strongly anchor the deposited platinum group metal (PGM) catalysts and induce a partial electron transfer between the PGM catalysts and support. Density Functional Theory (DFT) calculations reveal that the strong metal‐support interaction substantially increases the adsorption energy of OH, particularly near the N‐doping sites, which helps to compete and remove the adsorbed intermediate species generated during MOR. The PGM catalysts on N‐doped VACNF support exhibits CO stripping at lower potentials comparing to the commercial Vulcan carbon support and presents an enhanced electrocatalytic performance and better durability for MOR.
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Insights of Heteroatoms Doping‐Enhanced Bifunctionalities on Carbon Based Energy Storage and Conversion
Abstract Ever‐developing energy storage technologies demand the pursuit of advanced materials with multiple functionalities. Recent studies revealed that multiple heteroatom‐doped carbon has been wildly used for bi‐functional or even tri‐functional energy storage and conversion. However, few efforts have been made to uncover the origin of multi‐functionalities. Herein, a nitrogen, phosphorus, and sulfur tri‐doped carbon is designed in this work with large porosity, rich heteroatoms doping and high mass density, exhibiting excellent bifunctionalities on supercapacitors and oxygen reduction reaction. Importantly, the density functional theory calculations demonstrate the relevant co‐doping and tri‐doping generate more active sites on neighboring carbon atoms than single doping, and the same type of active sites may enhance bifunctionalities simultaneously. The present investigations provide a promising guidance on the design of multi‐functional materials for future energy storage and conversion applications.
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- Award ID(s):
- 1662288
- PAR ID:
- 10453762
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 31
- Issue:
- 11
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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