Thin Films of Fully Noble Metal-Free POM@MOF for Photo- catalytic Water Oxidation

Abstract : P2W18Co4@MOF-545, which contains the sandwich-type polyoxometalate (POM) [(PW9O34)2Co4(H2O)2]10– (P2W18Co4) immobilized in the porphyrinic metal–organic framework (MOF), MOF–545, is a “three-in-one” (porosity + light capture + catalysis) heterogeneous photosystem for the oxygen-evolution reaction (OER). Thin films of this composite were synthesized on transparent and conductive indium tin oxide (ITO) supports using electrophoretic (EP) or drop-casting (DC) methods, thus providing easy-to-use devices. Their electro- and photocatalytic activities for OER were investigated. Remarkably, both types of films exhibit higher turnover numbers (TONs) than the original bulk material previously studied as a suspension for the photocatalytic OER, with TONs after 2 h equal to 1600 and 403 for DC and EP films, respectively, compared to 70 for the suspension. This difference of catalytic activities is related to the proportion of efficiently illuminated crystallites, whereby a DC thin film offers the largest proportion of POM@MOF crystallites exposed to light due to its lower thickness when compared to an EP film or crystals in suspension. Such devices can be easily recycled by simply removing them from the reaction medium and washing them before reuse. The films were fully characterized with extended X-ray absorption fine structure (EXAFS) and X-ray absorption near edge structure (XANES) spectroscopies, Raman, scanning electron microscopy, and electrochemistry before and after catalysis. The combination of all of these techniques shows the stability of both the POM and the MOF within the composite upon water-oxidation reaction.
Document type :
Journal articles
Complete list of metadatas

Cited literature [65 references]  Display  Hide  Download

https://hal.sorbonne-universite.fr/hal-02451033
Contributor : Gestionnaire Hal-Su <>
Submitted on : Thursday, January 23, 2020 - 11:31:29 AM
Last modification on : Saturday, January 25, 2020 - 1:33:48 AM

File

 Restricted access
To satisfy the distribution rights of the publisher, the document is embargoed until : 2020-05-27

Please log in to resquest access to the document

Identifiers

Citation

Grégoire Paille, Maria Gomez-Mingot, Catherine Roch-Marchal, Mohamed Haouas, Youven Ben-Seghir, et al.. Thin Films of Fully Noble Metal-Free POM@MOF for Photo- catalytic Water Oxidation. ACS Applied Materials & Interfaces, Washington, D.C. : American Chemical Society, 2019, 11 (51), pp.47837-47845. ⟨10.1021/acsami.9b13121⟩. ⟨hal-02451033⟩

Share

Metrics

Record views

52