2026-04-17T19:26:39Zhttps://recercat.cat/oai/request

oai:recercat.cat:2072/3597832024-12-20T23:09:30Zcom_2072_300912com_2072_4427col_2072_301309

00925njm 22002777a 4500 dc Chen, Zupeng author Vorobyeva, Evgeniya author Mitchell, Sharon author Fako, Edvin author López, Núria author Collins, Sean M. author Leary, Rowan K. author Midgley, Paul A. author Hauert, Roland author Pérez-Ramírez, Javier author 2018-04-17 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. http://hdl.handle.net/2072/359783 https://doi.org/10.1093/nsr/nwy048 Single-atom heterogeneous catalysts based on distinct carbon nitride scaffolds