From Supramolecular Species to Self‐Templated Porous Carbon and Metal‐Doped Carbon for Oxygen Reduction Reaction Catalysts

• Published in: Angewandte Chemie International Edition Vol. 58; no. 15; pp. 4963 - 4967
• Main Authors: Xie, Jin, Li, Bo‐Quan, Peng, Hong‐Jie, Song, Yun‐Wei, Li, Jia‐Xing, Zhang, Ze‐Wen, Zhang, Qiang
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01-04-2019
• Edition: International ed. in English
• Subjects: Bonding; Bonding strength; Carbon; carbon nanomaterials; Catalysts; Chemical reduction; Cleavage; Decomposition reactions; electrocatalysis; Electrocatalysts; Fabrication; iron; Metals; Oxygen; oxygen reduction reaction; Oxygen reduction reactions; Precursors; Purification; Pyrolysis; supramolecular precursors; carbon nanomaterials; iron; supramolecular precursors; oxygen reduction reaction; electrocatalysis
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201814605

The preparation of carbon materials usually involves the decomposition of precursors and the reorganization of the as‐generated fragments. However, the cleavage of bonds and the simultaneous formation of new bonds at nearly the same positions prevents effective yet precise fabrication. Herein, a supramolecular precursor, cucurbit[6]uril, that contains multiple bonds with distinct bond strengths is proposed to decouple the twin problem of simultaneous bond cleavage and formation, allowing multistage transformations to hierarchical porous carbon and metal‐doped carbon in a single yet effective pyrolysis step without the need of a template or additional purification. As a proof‐of‐concept, the Fe‐doped carbon electrocatalysts realized a Pt/C‐like half‐wave potential of 0.869 V vs. RHE and small Tafel slope of 51.3 mV dec−1 in oxygen reduction reaction.
Making mesopores: The supramolecular interactions within cucurbit[6]uril enable a step by step pyrolysis mechanism, which aids the construction of mesopores and heteroatom doping in the resulting carbon material. The iron‐doped mesoporous carbon is highly efficient in the oxygen reduction reaction (ORR).