The mechanism of CO₂ hydration: a porous metal oxide nanocapsule catalyst can mimic the biological carbonic anhydrase role

Abstract

The mechanism for the hydration of CO2 within a Keplerate nanocapsule is presented. A network of hydrogen bonds across the water layers in the first metal coordination sphere facilitates the proton abstraction and nucleophilic addition of water. The highly acidic properties of the polyoxometalate cluster are crucial for explaining the catalysed hydration.

A Molecular CO2 Reduction Catalyst Based on Giant Polyoxometalate {Mo368}

“…On the other hand, the {Mo 2 } unit and {Mo 1 } unit plays a crucial role for photochemical CO 2 reduction. It has been already shown by Müller group that CO 2 can coordinate with {Mo 2 } units of the giant molybdenum based polyoxometalates (Garai et al, 2012 ; Bandeira et al, 2015 ). Thus, in our present case it is also reasonable to postulate that CO 2 can co-ordinate with {Mo 2 } unit.…”

“…The CO 2 concentration in environment is ever increasing. Thus, to find out a suitable pathway to recycle CO 2 to an energy rich material is a crucial challenge nowadays (Hoffert et al, 2002 ; Crabtree and Lewis, 2007 ; Meinshausen et al, 2009 ; Mikkelsen et al, 2010 ; Garai et al, 2012 ; Bandeira et al, 2015 ; Twidell and Weir, 2015 ). The depletion of fossil fuel during production of energy increases the CO 2 level in the environment (Hoel and Kverndokk, 1996 ; Höök and Tang, 2013 ).…”

Regioselective Catalysis by the {Mo132} Nanocapsule: A Computational Inspection

“…To study the reaction pathway using a model of the whole of the Keplerate sphere, despite its high symmetry, would be computationally intractable; so instead, we chose to employ a reliable and minimal cluster model known to capture the reactivity trends of the Keplerate sphere, as described previously in the literature , . The original authors noticed that upon mixing the reagents, within a few minutes, a mixture of encapsulated azidoacetate/propiolate is detectable by NMR spectroscopy, so that it becomes unclear if the reaction initiates from the azidoacetate or the propiolate chelate.…”

Electronic Structure Studies on the Whole Keplerate Family: Predicting New Members

“…[26] Also, it has been provedt hat the Mo 132 Keplerate is able to modify the regioselectivity of the Huisgen reaction. [27] Other examples refer to the uptake and oxidation of simple gases as CO 2 [8,28] and SO 2 [7] inside the Mo 132 capsule;i nb oth cases, the products were characterized by X-Ray crystallography.S everalo ther catalytic oxidation processes have been reported,w hich in our opinion probably occur outside the capsule. [29] Besides their catalytic applications,n ew materials are being prepared that employ Keplerates.…”