Release Time:2019-03-09 Hits:
Indexed by: Journal Article
Date of Publication: 2010-04-19
Journal: CHEMISTRY-A EUROPEAN JOURNAL
Included Journals: EI、SCIE
Volume: 16
Issue: 15
Page Number: 4659-4668
ISSN: 0947-6539
Key Words: electrochemistry; homogeneous catalysis; oxidation; ruthenium; water splitting
Abstract: Two mononuclear ruthenium complexes [RuL(pic)(3)] (1) and [RuL(bpy)(pic)] (2) (H(2)L = 2,6-pyridinedicarboxylic acid, pic=4-picoline, bpy = 2,2'-bipyridine) have been synthesized and fully characterized. Both complexes could promote water oxidation chemically and photochemically. Compared with other known ruthenium-based water oxidation catalysts using [Ce(NH(4))(2)(NO(3))(6)] (Ce(IV)) as the oxidant in solution at pH 1.0, complex 1 is one of the most active catalysts yet reported with an initial rate of 0.23 turnovers(-1). Under acidic conditions, the equatorial 4-picoline in complex 1 dissociates first. In addition, ligand exchange in 1 occurs when the Rum state is reached. Based on the above observations and MS measurements of the intermediates during water oxidation by 1 using Ce(IV) as oxidant, [RuL(pic)(2)(H(2)O)](+) is proposed as the real water oxidation catalyst.