Heterogenized Iridium Water-Oxidation Catalyst from a Silatrane
نویسندگان
چکیده
8 ABSTRACT: A pentamethylcyclopentadienyl (Cp*) iridium water9 oxidation precatalyst was modified to include a silatrane functional group 10 for covalent attachment to metal oxide semiconductor surfaces. The 11 heterogenized catalyst was found to perform electrochemically driven 12 water oxidation at an overpotential of 462 mV with a turnover number of 13 304 and turnover frequency of 0.035 s−1 in a 0.1 M KNO3 electrolyte at 14 pH 5.8. Computational modeling of experimental IR spectra suggests that 15 the catalyst retains its Cp* group during the first hour of catalysis and likely 16 remains monomeric.
منابع مشابه
A molecular catalyst for water oxidation that binds to metal oxide surfaces
Molecular catalysts are known for their high activity and tunability, but their solubility and limited stability often restrict their use in practical applications. Here we describe how a molecular iridium catalyst for water oxidation directly and robustly binds to oxide surfaces without the need for any external stimulus or additional linking groups. On conductive electrode surfaces, this hete...
متن کاملHeterogenized Water Oxidation Catalysts Prepared by Immobilizing Kläui-Type Organometallic Precursors.
An efficient heterogenized water oxidation catalyst (2_TiO2 ) has been synthesized by immobilizing the Kläui-type organometallic precursor [Cp*Ir{P(O)(OH)2 }3 ]Na (2, Cp*=1,2,3,4,5-pentamethylcyclopentadienyl ligand) onto rutile TiO2 . Iridium is homogeneously distributed at the molecular and atomic/small cluster level in 2_TiO2 and 2'_TiO2 (solid catalyst recovered after the first catalytic ru...
متن کاملAnodic deposition of a robust iridium-based water-oxidation catalyst from organometallic precursors†
Artificial photosynthesis, modeled on natural light-driven oxidation of water in Photosystem II, holds promise as a sustainable source of reducing equivalents for producing fuels. Few robust wateroxidation catalysts capable of mediating this difficult four-electron, four-proton reaction have yet been described. We report a new method for generating an amorphous electrodeposited material, princi...
متن کاملWilkinson's iridium acetate trimer as a water-oxidation catalyst.
The catalytic water-oxidation activity of Wilkinson's iridium acetate trimer (1) has been characterized electrochemically and by using chemical oxidants. We show that 1 can function as an operationally homogeneous water-oxidation catalyst when driven with sodium periodate as a primary oxidant, but rapidly decomposes using Ce(IV) as a primary oxidant.
متن کاملIridium-based complexes for water oxidation.
Organometallic Ir precatalysts have been found to yield homogeneous Ir-based water-oxidation catalysts (WOCs) with very high activity. The Cp*Ir catalyst series can operate under a variety of regimes: it can either act as a homogeneous or a heterogeneous catalyst; it can be driven by chemical, photochemical, or electrochemical methods; and the molecular catalyst can either act in solution or su...
متن کامل