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Indexed by:期刊论文

Date of Publication:2010-04-19

Journal:CHEMISTRY-A EUROPEAN JOURNAL

Included Journals:SCIE、EI

Volume:16

Issue:15

Page Number:4659-4668

ISSN No.: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.