Abstract
Porous CoNC catalysts with ultrahigh surface area are highly required for catalytic reactions. Here, a scale-up method to synthesize gram-quantities of isolated Co single-site catalysts anchored on N-doped porous carbon nanobelt (Co-ISA/CNB) by pyrolysis of biomass-derived chitosan is reported. The usage of ZnCl2 and CoCl2 salts as effective activation–graphitization agents can introduce a porous belt-like nanostructure with ultrahigh specific surface area (2513 m2 g−1) and high graphitization degree. Spherical aberration correction electron microscopy and X-ray absorption fine structure analysis reveal that Co species are present as isolated single sites and stabilized by nitrogen in CoN4 structure. All these characters make Co-ISA/CNB an efficient catalyst for selective oxidation of aromatic alkanes at room temperature. For oxidation of ethylbenzene, the Co-ISA/CNB catalysts yield a conversion up to 98% with 99% selectivity, while Co nanoparticles are inert. Density functional theory calculations reveal that the generated CoO centers on isolated Co single sites are responsible for the excellent catalytic efficiency.
Original language | English |
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Article number | 1802167 |
Journal | Advanced Functional Materials |
Volume | 28 |
Issue number | 37 |
DOIs | |
Publication status | Published - 12 Sept 2018 |
Externally published | Yes |
Keywords
- 2D nanobelt
- biomass
- cobalt
- porous carbon
- single-site catalysts