Publications by authors named "Gabriel Menendez Rodriguez"
Herein, we report reversible electrocatalytic NAD/NADH interconversion mediated by [Cp*Ir(pyza)Cl] (, pyza = pyrazine amidate). was designed through a rational approach aimed at lowering the overpotential of NAD to NADH reduction with respect to that observed for electrocatalyst [Cp*Ir(pica)Cl] (, pica = picolinamidate). The peculiar properties of pyza, which is substantially less σ electron-donator and more π electron-acceptor than pica, resulted in an easier bielectronic reduction process occurring at -0.
View Article and Find Full Text PDF[Cp*Ir(R-pica)Cl] (Cp*=pentamethylcyclopentadienyl anion, pica=2-picolineamidate) complexes bearing carbohydrate substituents on the amide nitrogen atom (R=methyl-β-D-gluco-pyranosid-2-yl, 1; methyl-3,4,6-tri-O-acetyl-β-D-glucopyranosid-2-yl, 2) were tested as catalysts for formic acid dehydrogenation in water. TOF values over 12000 h and 50000 h were achieved at 333 K for 1 and 2, respectively, with TON values over 35000 for both catalysts. Comparison with the simpler cyclohexyl-substituted analogue (3) indicated that glucosyl-based complexes are much better performing under the same experimental conditions (TOF=5144 h, TON=5000 at pH 2.
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- Recent advancements in electrocatalytic oxygen evolution reaction (OER) show that earth-abundant catalysts still lack optimal efficiency due to complexities in the catalytic system.
- The study focuses on the impact of the tunable 3D configuration of metal centers, specifically in one-dimensional coordination polymers made of metals like Fe, Co, and Ni, which helps clarify their catalytic performance.
- Findings reveal that electronic structure, including metal spin and oxidation state, significantly affect ligand binding and can potentially reduce overpotential in OER, aiding in the design of more effective catalysts.
The degradation pathways of highly active [Cp*Ir(κ -N,N-R-pica)Cl] catalysts (pica=picolinamidate; 1 R=H, 2 R=Me) for formic acid (FA) dehydrogenation were investigated by NMR spectroscopy and DFT calculations. Under acidic conditions (1 equiv. of HNO ), 2 undergoes partial protonation of the amide moiety, inducing rapid κ -N,N to κ -N,O ligand isomerization.
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- Electrochemical water oxidation faces challenges due to high overpotentials required by current catalysts, primarily iridium and ruthenium oxides.
- A study analyzed the impact of hydroxyl positions in hydroxylpicolinate ligands on the efficiency of various iridium catalysts for water oxidation, finding limited correlation between structure and performance in electrochemical conditions.
- Experiments showed that iridium complexes formed deposits on electrodes with specific binding energies, and the performance of newly deposited materials from ligand-free iridium yielded significantly higher currents compared to molecular complexes, indicating potential advantages in using colloidal iridium oxide nanoparticles.
Water oxidation (WO) is a central reaction in the photo- and electro-synthesis of fuels. Iridium complexes have been successfully exploited as water oxidation catalysts (WOCs) with remarkable performances. Herein, we report a systematic study aimed at benchmarking well-known Ir WOCs, when NaIO is used to drive the reaction.
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