Ultrathin Hollow Co/N/C Spheres from Hyper-Crosslinked Polymers by a New Universal Strategy with Boosted ORR Efficiency.
Small
; 19(16): e2207646, 2023 Apr.
Article
em En
| MEDLINE
| ID: mdl-36670080
ABSTRACT
Porous carbon materials with hollow structure, on account of the extraordinary morphology, reveal fascinating prospects in lithium-ion batteries, electrocatalysis, etc. However, collapse in ultrathin carbon spheres due to insufficient rigidity in such thin materials obstructs further enhanced capability. Based on hyper-crosslinked polymers (HCPs) with sufficient pore structure and rigid framework, a new bottom-up strategy is proposed to construct SiO2 @HCPs directly from aromatic monomers. Heteroatom and function groups can be facilely introduced to the skeleton. The thickness of HCPs' wall can be tuned from 9 to 20 nm, which is much thinner than that of hollow sphere synthesized by the traditional method, and the sample with a thickness of 20 nm shows the highest surface area of 1633 m2 g-1 . The oxygen reduction reaction is conducted and the CoNHCS electrocatalysts with an ultrathin thickness of 5 nm display higher half-wave potential than those of bulk samples, even better than commercial Pt/C electrode. On account of the hollow structure, the relative current density loss of electrocatalysts is only 4.1% in comparison with 27.7% in Pt/C electrode during the 15 000 s test, indicating an obvious higher long-term stability. The new strategy to construct hollow HCPs may shed light on efficient chemical catalysis, drug delivery, and electrocatalysis.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Ano de publicação:
2023
Tipo de documento:
Article