Electrochemically activated coordenative assembly of a triruthenium cluster metallopolymer
- 作者：Sergio H. Toma ; sergioht@iq.usp.br ; sergioht@gmail.com ; Jonnatan J. Santos ; Rodrigo G. Velho ; Marcelo Nakamura ; Henrique E. Toma ; Koiti Araki ; koiaraki@iq.usp.br
- 关键词：Electropolymerization ; Metallopolymers ; Coordinative assembly ; Triruthenium clusters
- 刊名：Electrochimica Acta
- 出版年：2012
- 期刊代码：30_00134686
- 类别：ch
- 出版时间：1 April, 2012
- 卷：66
- 期：Complete
- 页码：287-294
- 文件大小：1187 K
摘要
A general strategy for electrochemically induced assembly of coordination metallopolymers is demonstrated using the tritopic bridging [Ru3(渭3O)(CH3COO)6(pytpy)3]+ cluster complex, where pytpy is the 4鈥?(4-pyridyl)-2,2鈥?6鈥?2鈥?terpyridine ligand, and iron(III) ions. The concept of such an electrochemically induced coordinative assembly was proven exploring the large difference in the [Fe(pytpy)2] complex formation constants depending on the iron ion oxidation state. Much more stable bridging complexes are formed in the presence of Fe(II) in contrast to Fe(III) ions. The build-up of electrochemically active films on FTO electrodes was confirmed by the growth of the corresponding voltammetric peaks concomitantly with the rise of typical triruthenium cluster and [Fe(pytpy)2]2+ complex absorption bands. The metallopolymer was constituted by agglomerates of more or less fused tape like structures, exhibiting large voids and pinholes, as revealed by SEM and AFM images. The adhesion/deposition on FTO was improved by functionalizing the surface with TES-tpy and HOOC-tpy, which increased the surface coverage up to 80%, as estimated by impedance spectroscopy.