In:
ChemSusChem, Wiley, Vol. 10, No. 3 ( 2017-02-08), p. 551-561
Abstract:
The irreversible conversion of single‐site water‐oxidation catalysts (WOC) into more rugged catalysts structurally related to [(trpy)(5,5′‐X 2 ‐bpy)Ru IV (μ‐O)Ru IV (trpy)(O)(H 2 O)] 4+ (X=H, 1‐dn 4+ ; X=F, 2‐dn 4+ ; bpy=2,2′‐bipyridine; trpy=2,2′:6′,2“‐terpyridine) represents a critical issue in the development of active and durable WOCs. In this work, the electrochemical and acid–base properties of 1‐dn 4+ and 2‐dn 4+ were evaluated. In situ resonance Raman spectroscopy was employed to characterize the species formed upon the stoichiometric oxidation of the single‐site catalysts and demonstrated the formation of high‐oxidation‐state mononuclear Ru=O and RuO−O complexes. Under turnover conditions, the dinuclear intermediates, 1‐dn 4+ and 2‐dn 4+ as well as the previously proposed [Ru VI (trpy)(O) 2 (H 2 O)] 2+ complex ( 3 2+ ) are formed. Complex 3 2+ is a pivotal intermediate that provides access to the formation of dinuclear species. Single‐crystal X‐ray diffraction analysis of the isolated complex [Ru IV (O)(trpy)(5,5′‐F 2 ‐bpy)] 2+ reveals a clear elongation of the Ru−N bond trans to the oxido ligand that documents the weakness of this bond, which promotes the release of the bpy ligand and the subsequent formation of 3 2+ .
Type of Medium:
Online Resource
ISSN:
1864-5631
,
1864-564X
DOI:
10.1002/cssc.201601221
Language:
English
Publisher:
Wiley
Publication Date:
2017
detail.hit.zdb_id:
2411405-4
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