Prussian White as a highly active molecular catalyst for proton reduction

We report a highly active copper-based catalyst for electrochemical CO2 reduction. Electrochemical analysis revealed that the maximum turnover frequency for CO2 to CO conversion reached to 1,460,000 s-1 at an...

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A Water-Soluble Sodium Pectate Complex with Copper as an Electrochemical Catalyst for Carbon Dioxide Reduction

Molecules ◽

10.3390/molecules26185524 ◽

2021 ◽

Vol 26 (18) ◽

pp. 5524

Author(s):

Kirill V. Kholin ◽

Mikhail N. Khrizanforov ◽

Vasily M. Babaev ◽

Guliya R. Nizameeva ◽

Salima T. Minzanova ◽

...

Keyword(s):

Co2 Reduction ◽

Reduction Reaction ◽

Water Soluble ◽

Molecular Catalyst ◽

Electrochemical Catalyst ◽

Highly Active ◽

Electrochemical Co2 Reduction ◽

The Stability ◽

Molecular Catalysts ◽

Co2 Reduction Reaction

A selective noble-metal-free molecular catalyst has emerged as a fruitful approach in the quest for designing efficient and stable catalytic materials for CO2 reduction. In this work, we report that a sodium pectate complex of copper (PG-NaCu) proved to be highly active in the electrocatalytic conversion of CO2 to CH4 in water. Stability and selectivity of conversion of CO2 to CH4 as a product at a glassy carbon electrode were discovered. The copper complex PG-NaCu was synthesized and characterized by physicochemical methods. The electrochemical CO2 reduction reaction (CO2RR) proceeds at −1.5 V vs. Ag/AgCl at ~10 mA/cm2 current densities in the presence of the catalyst. The current density decreases by less than 20% within 12 h of electrolysis (the main decrease occurs in the first 3 h of electrolysis in the presence of CO2). This copper pectate complex (PG-NaCu) combines the advantages of heterogeneous and homogeneous catalysts, the stability of heterogeneous solid materials and the performance (high activity and selectivity) of molecular catalysts.

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Highly active electrocatalysis by cobalt tetraphenylporphyrin incorporated in a Nafion membrane for proton reduction

Polymers for Advanced Technologies ◽

10.1002/(sici)1099-1581(199809)9:9<559::aid-pat818>3.0.co;2-1 ◽

1998 ◽

Vol 9 (9) ◽

pp. 559-562 ◽

Cited By ~ 46

Author(s):

Toshiyuki Abe ◽

Fumio Taguchi ◽

Hiroshi Imaya ◽

Feng Zhao ◽

Jian Zhang ◽

...

Keyword(s):

Nafion Membrane ◽

Proton Reduction ◽

Highly Active

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Bio-inspired CO2reduction by a rhenium tricarbonyl bipyridine-based catalyst appended to amino acids and peptidic platforms: incorporating proton relays and hydrogen-bonding functional groups

Faraday Discussions ◽

10.1039/c7fd00003k ◽

2017 ◽

Vol 198 ◽

pp. 279-300 ◽

Cited By ~ 27

Author(s):

S. A. Chabolla ◽

C. W. Machan ◽

J. Yin ◽

E. A. Dellamary ◽

S. Sahu ◽

...

Keyword(s):

Amino Acids ◽

Md Simulations ◽

Catalyst Design ◽

Nmr Studies ◽

Molecular Catalyst ◽

Peptide Catalysts ◽

Highly Active ◽

Bipyridine Ligand ◽

Novel Catalyst

Herein, we report a new approach to bio-inspired catalyst design. The molecular catalyst employed in these studies is based on the robust and selective Re(bpy)(CO)3Cl-type (bpy = 2,2′-bipyridine) homogeneous catalysts, which have been extensively studied for their ability to reduce CO2electrochemically or photochemically in the presence of a photosensitizer. These catalysts can be highly active photocatalysts in their own right. In this work, the bipyridine ligand was modified with amino acids and synthetic peptides. These results build on earlier findings wherein the bipyridine ligand was functionalized with amide groups to promote dimer formation and CO2reduction by an alternate bimolecular mechanism at lower overpotential (ca.250 mV) than the more commonly observed unimolecular process. The bio-inspired catalysts were designed to allow for the incorporation of proton relays to support reduction of CO2to CO and H2O. The coupling of amino acids tyrosine and phenylalanine led to the formation of two structurally similar Re catalyst/peptide catalysts for comparison of proton transport during catalysis. This article reports the synthesis and characterization of novel catalyst/peptide hybrids by molecular dynamics (MD simulations of structural dynamics), NMR studies of solution phase structures, and electrochemical studies to measure the activities of new bio-inspired catalysts in the reduction of CO2.

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Replacing Pyridine with Pyrazine in Molecular Cobalt Catalysts: Effects on Electrochemical Properties and Aqueous H2 Generation

Catalysts ◽

10.3390/catal11010075 ◽

2021 ◽

Vol 11 (1) ◽

pp. 75

Author(s):

Lars Kohler ◽

Andrea M. Potocny ◽

Jens Niklas ◽

Matthias Zeller ◽

Oleg G. Poluektov ◽

...

Keyword(s):

Catalytic Activity ◽

Molecular Geometry ◽

Cobalt Catalysts ◽

Single Atom ◽

Proton Reduction ◽

Substantial Impact ◽

Minimal Impact ◽

Molecular Catalyst ◽

Reduction Potentials ◽

The Difference

Four new molecular Co(II)tetrapyridyl complexes were synthesized and evaluated for their activity as catalysts for proton reduction in aqueous environments. The pyridine groups around the macrocycle were substituted for either one or two pyrazine groups. Single crystal X-ray analysis shows that the pyrazine groups have minimal impact on the Co(II)–N bond lengths and molecular geometry in general. X-band EPR spectroscopy confirms the Co(II) oxidation state and the electronic environment of the Co(II) center are only very slightly perturbed by the substitution of pyrazine groups around the macrocycle. The substitution of pyrazine groups has a substantial impact on the observed metal- and ligand-centered reduction potentials as well as the overall H2 catalytic activity in a multimolecular system using the [Ru(2,2′-bipyridine)3]Cl2 photosensitizer and ascorbic acid as a sacrificial electron donor. The results reveal interesting trends between the H2 catalytic activity for each catalyst and the driving force for electron transfer between either the reduced photosensitizer to catalyst step or the catalyst to proton reduction step. The work presented here showcases how even the difference of a single atom in a molecular catalyst can have an important impact on activity and suggests a pathway to optimize the photocatalytic activity and stability of molecular systems.

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Effect of pomegranate fruit supplementation on performance and various markers in athletes and active subjects: a systematic review

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000601 ◽

2019 ◽

pp. 1-15

Author(s):

Alicja Urbaniak ◽

Anna Skarpańska-Stejnborn

Keyword(s):

Vessel Diameter ◽

Whole Body ◽

Double Blind Study ◽

Double Blind ◽

Physically Active ◽

Highly Active ◽

Body Strength ◽

Rate Of Increase ◽

Study Designs ◽

Pomegranate Fruit

Abstract. The aim of the study was to review recent findings on the use of POM supplements in athletes of various disciplines and physically active participants. Eleven articles published between 2010 and 2018 were included, where the total number of investigated subjects was 176. Male participants constituted the majority of the group (n = 155), as compared to females (n = 21). 45% of research described was conducted on athletes, whereas the remaining studies were based on highly active participants. Randomised, crossover, double-blind study designs constituted the majority of the experimental designs used. POM supplementation varied in terms of form (pills/juice), dosage (50 ml–500 ml) and time of intervention (7 days–2 months) between studies. Among the reviewed articles, POM supplementation had an effect on the improvement of the following: whole body strength; feeling of vitality; acute and delayed muscle fatigue and soreness; increase in vessel diameter; blood flow and serum level of TAC; reduction in the rate of increase for HR, SBP, CK and LDH; support in the recovery of post-training CK, LDH, CRP and ASAT to their baseline levels; reduction of MMP2, MMP9, hsCRP and MDA; and increased activity of antioxidant enzymes (glutathione peroxidase and superoxide dismutase). In the majority of reviewed articles POM supplementation had a positive effect on a variety of parameters studied and the authors recommended it as a supplement for athletes and physically active bodies.

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