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

ABSTRACT: Photocatalytic CO₂ reduction in water is one of the most attractive research pursuits of our time. In this article we report a giant polyoxometalate {Mo₃₆₈} based homogeneous catalytic system, which efficiently reduces CO₂ to formic acid with a maximum turnover number (TON) of 27,666, turnover frequency (TOF) of 4,611 h^-1 and external quantum efficiency of the reaction is 0.6%. The catalytic system oxidizes water and releases electrons, and these electrons are further utilized for the reduction of CO₂ to formic acid. A maximum of 8.3 mmol of formic acid was observed with the loading of 0.3 μmol of the catalyst. Our catalyst material is also stable throughout the reaction. The starting materials for this experiment are CO₂ and H₂O and the end products are HCOOH and O₂. The formic acid formed in this reaction is an important H₂ gas carrier and thus significant in renewable energy research.

SUBMITTER: Das S

PROVIDER: S-EPMC6224680 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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

Das Santu S Balaraju Tuniki T Barman Soumitra S Sreejith S S SS Pochamoni Ramudu R Roy Soumyajit S

Frontiers in chemistry 20181102

Photocatalytic CO2 reduction in water is one of the most attractive research pursuits of our time. In this article we report a giant polyoxometalate {Mo368} based homogeneous catalytic system, which efficiently reduces CO2 to formic acid with a maximum turnover number (TON) of 27,666, turnover frequency (TOF) of 4,611 h-1 and external quantum efficiency of the reaction is 0.6%. The catalytic system oxidizes water and releases electrons, and these elect ...[more]

PMID: 30450356

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

Project description:[This corrects the article DOI: 10.3389/fchem.2018.00514.].

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| S-EPMC11342151 | biostudies-literature

Exploring the Molecular Growth of Two Gigantic Half-Closed Polyoxometalate Clusters {Mo180 } and {Mo130 Ce6 }.

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Electrochemical Water Oxidation and CO2 Reduction with a Nickel Molecular Catalyst.

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Project description:Precise synthesis of polyoxometalates (POMs) is important for the fundamental understanding of the relationship between the structure and function of each building motif. However, it is a great challenge to realize the atomic-level tailoring of specific sites in POMs without altering the major framework. Herein, we report the case of Ce-mediated molecular tailoring on gigantic {Mo132}, which has a closed structural motif involving a never seen {Mo110} decamer. Such capped wheel {Mo132} undergoes a quasi-isomerism with known {Mo132} ball displaying different optical behaviors. Experiencing an 'Inner-On-Outer' binding process with the substituent of {Mo2} reactive sites in {Mo132}, the site-specific Ce ions drive the dissociation of {Mo2*} clipping sites and finally give rise to a predictable half-closed product {Ce11Mo96}. By virtue of the tailor-made open cavity, the {Ce11Mo96} achieves high proton conduction, nearly two orders of magnitude than that of {Mo132}. This work offers a significant step toward the controllable assembly of POM clusters through a Ce-mediated molecular tailoring process for desirable properties.

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A donor-chromophore-catalyst assembly for solar CO2 reduction.

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Mo2C-induced hydrogen production enhances microbial electrosynthesis of acetate from CO2 reduction.

Project description:BackgroundMicrobial electrosynthesis (MES) is a biocathode-driven process, in which electroautotrophic microorganisms can directly uptake electrons or indirectly via H2 from the cathode as energy sources and CO2 as only carbon source to produce chemicals.ResultsThis study demonstrates that a hydrogen evolution reaction (HER) catalyst can enhance MES performance. An active HER electrocatalyst molybdenum carbide (Mo2C)-modified electrode was constructed for MES. The volumetric acetate production rate of MES with 12 mg cm-2 Mo2C was 0.19 ± 0.02 g L-1 day-1, which was 2.1 times higher than that of the control. The final acetate concentration reached 5.72 ± 0.6 g L-1 within 30 days, and coulombic efficiencies of 64 ± 0.7% were yielded. Furthermore, electrochemical study, scanning electron microscopy, and microbial community analyses suggested that Mo2C can accelerate the release of hydrogen, promote the formation of biofilms and regulate the mixed microbial flora.ConclusionCoupling a HER catalyst to a cathode of MES system is a promising strategy for improving MES efficiency.

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