Title:
|
Single-atom heterogeneous catalysts based on distinct carbon nitride scaffolds
|
Author:
|
Chen, Zupeng; Vorobyeva, Evgeniya; Mitchell, Sharon; Fako, Edvin; López, Núria; Collins, Sean M.; Leary, Rowan K.; Midgley, Paul A.; Hauert, Roland; Pérez-Ramírez, Javier
|
Abstract:
|
Carbon nitrides integrating macroheterocycles offer unique potential as hosts for stabilizing metal atoms
due to their rich electronic structure. To date, only graphitic heptazine-based polymers have been studied.
Here, we demonstrate that palladium atoms can be effectively isolated on other carbon nitride scaffolds
including linear melem oligomers and poly(triazine/heptazine imides). Increased metal uptake was linked
to the larger cavity size and the presence of chloride ions in the polyimide structures. Changing the host
structure leads to significant variation in the average oxidation state of the metal, which can be tuned by
exchange of the ionic species as evidenced by X-ray photoelectron spectroscopy and supported by density
functional theory. Evaluation in the semi-hydrogenation of 2-methyl-3-butyn-2-ol reveals an inverse
correlation between the activity and the degree of oxidation of palladium, with oligomers exhibiting the
highest activity.These findings provide new mechanistic insights into the influence of the carbon nitride
structure on metal stabilization. |
Publication date:
|
2018-04-17 |
Subject(s):
|
54 |
Rights:
|
L'accés als continguts d'aquest document queda condicionat a l'acceptació de les condicions d'ús establertes per la següent llicència Creative Commons:http://creativecommons.org/licenses/by-nc-nd/4.0/ |
Pages:
|
642 p. |
Document type:
|
Article Article - Accepted version |
DOI:
|
10.1093/nsr/nwy048
|
Share:
|
|