Design of Metal-to-Metal Charge-Transfer Chromophores for Visible-Light Activation of Oxygen-Evolving Mn Oxide Catalysts in a Polymer Film
In: Chemistry of Materials, 2024, Heft Preprints
serialPeriodical
Zugriff:
To construct photoresponsive unidirectional charge transfer units for the activation of oxygen-evolving manganese oxide (MnOx) catalyst, metal-oxide nanoclusters consisting of cerium (CeIII) or cobalt (CoII) ions and Keggin-type polyoxotungstate (PW12O403–) were synthesized in a polymer matrix as visible-light-absorbing chromophores. The utilization of the polymer matrix enabled the molecularly dispersed PW12O403–states and was advantageous to achieve product-separable energy conversion systems. The reaction of PW12O403–with Ce(NO3)3or CoCl2in the polymer matrix generated the new broad absorption tails extending from the UV to visible region, assignable to metal-to-metal charge transfer (MMCT) transitions of oxo-bridged binuclear WVI–O–CeIIIand WVI–O–CoIIunits. Cyclic voltammetry analysis of the oxo-bridged binuclear units in the polymer membrane revealed that the CoIII/CoIIcouple had a 300 mV more positive redox potential than that of CeIV/CeIIIand was capable of extracting electrons from MnOxcatalyst. Although visible-light irradiation of the polymer membrane having WVI–O–CoIIunits resulted in negligible photocurrent generation, a clear anodic photocurrent response assigned to photoinduced WVI–O–CoII→ WV–O–CoIIItransition was observed after the coupling of MnOxcatalysts to WVI–O–CoIIunits. This finding demonstrated that the generation of anodic photocurrent is derived from the activation of MnOxcatalyst by the photogenerated CoIIIthrough confined WVI–O–CoIIlinkages. The system in this work based on POM and polymer, and its synthetic method provide us a novel methodology to develop artificial photosynthetic systems with spatially and energetically optimized components.
Titel: |
Design of Metal-to-Metal Charge-Transfer Chromophores for Visible-Light Activation of Oxygen-Evolving Mn Oxide Catalysts in a Polymer Film
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Autor/in / Beteiligte Person: | Yamaguchi, Akira ; Takashima, Toshihiro ; Hashimoto, Kazuhito ; Nakamura, Ryuhei |
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Zeitschrift: | Chemistry of Materials, 2024, Heft Preprints |
Veröffentlichung: | 2024 |
Medientyp: | serialPeriodical |
ISSN: | 0897-4756 (print) |
DOI: | 10.1021/acs.chemmater.7b01669 |
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