Galvanostatic Electroshock Synthesis of Low Loading Au-Pt Nanoalloys onto Gas Diffusion Electrodes as Multifunctional Electrocatalysts for a Glycerol-Fed Electrolyzer.

Water electrolysis is increasingly considered a viable solution for meeting the world's growing energy demands and mitigating environmental issues. An inventive strategy to mitigate the energy requirements involves substituting the energy-intensive oxygen evolution reaction (OER) with biomass-derived glycerol electrooxidation. Nonetheless, the synthesis of electrocatalysts for controlling the selectivity towards added-value chemicals at the anode and efficient H2 generation at the cathode remains a critical bottleneck. Herein, we implemented a galvanostatic electroshock synthesis approach to control the reduction kinetics of Au(III) and Pt(IV) to grow ultra-low amount of gold-platinum alloys on a gas diffusion electrode (12-26 µgmetal cm‒2) for glycerol-fed hydroxide anion exchange membrane based electrolyzer. The symmetric GDE-Au100-xPtx||GDE-Au100-xPtx systems showed a notable improvement in electrolyzer performance (GDE-Au64Pt36 = 201 mA cm-2) as compared to monometallic versions (GDE-Au100Pt0 = 18 mA cm-2, GDE-Au0Pt100 = 81 mA cm-2). Chromatography (HPLC) analysis underscores the critical importance of bulk electrolysis methodology (galvanostatic vs potentiostatic) for the efficient conversion of glycerol into high-value-added products. Regarding the electrical energy required to produce 1 kg of H2 for such an electrolyzer fed at the anode with glycerol, our results confirm a drastic decrease by a factor of at least two compared with conventional water electrolysis.

Design of three-dimensional electrocatalytic all-in-one electrodes by leveraging electrospinning and calcination approaches.

We report the combination of electrospinning and calcination to synthesize many free-standing electrocatalytic electrodes made of nanostructured nickel particles (active sites) and three-dimensional carbon microfibers (support). Precisely, we have used five different nickel precursors to elucidate the nitrogen origin (polyacrylonitrile or metal salts) and the impact on the electrocatalytic properties.

Ultrasound-assisted synthesis and characterization of a new metal-organic framework based on azobenzene-4,4-dicarboxylic acid: Precursor for the fabrication of Co3O4 nano-particles.

Azobenzene groups are widely known as photochromic ligands thus are particularly interesting building blocks for designing receptors for neutral or charged guests. A new metal-organic framework, [Co3(adc)3(DMF)4].2DMF (compound 1) (adc = azobenzene-4,4-dicarboxylic acid, DMF = N,N-dimethylformamide), was synthesized by solvothermal methods and structurally characterized using X-ray crystallography and a range of spectroscopic techniques. Also, nanorods of compound 1 have been synthesized by a sonochemical process and characterized by field emission scanning electron microscopy (FE-SEM) and powder X-ray diffraction (PXRD). The effect of sonication time and concentration of the initial reagents on the size and morphology of the MOF have been optimized. Results indicate that decreasing of initial concentration and increasing ultrasound radiation time lead to small size nanorods of compound 1. Thus, ultrasound radiation affects the size of nanorods. After heat treatment, the cobalt ion-based metal organic framework nanorods can be converted into porous Co3O4 nanoparticles.

N'-[(E)-2-Hy-droxy-5-iodo-benzyl-idene]-4-methyl-benzene-sulfono-hydrazide.

In the title mol-ecule, C(14)H(13)IN(2)O(3)S, the dihedral angle between the planes of the benzene and toluene rings is 84.3 (3)°. The mol-ecule displays a trans conformation with respect to the C=N bond. There is an intra-molecular O-H⋯N hydrogen bond with the azomethine N atom as acceptor. In the crystal, N-H⋯O hydrogen bonds connect the mol-ecules into chains running along the b axis.

trans-Diaqua-bis-(l-phenyl-alaninato-κ(2)N,O)nickel(II).

In the title compound, [Ni(C(9)H(10)NO(2))(2)(H(2)O)(2)], the coordination geometry around the Ni(II) ion can be described as distorted octa-hedral, with two N atoms and two O atoms from phenyl-alaninate ligands in the basal plane and two aqua O atoms at the axial sites. The crystal packing is stabilized by inter-molecular O-H⋯O and N-H⋯O hydrogen bonds.

Concentration dependent tautomerism in green [Cu(HL¹)(L²)] and brown [Cu(L¹)(HL²)] with H2L¹ = (E)-N'-(2-hydroxy-3-methoxybenzylidene)benzoylhydrazone and HL² = pyridine-4-carboxylic (isonicotinic) acid.

The in situ formed hydrazone Schiff base ligand (E)-N'-(2-hydroxy-3-methoxybenzylidene)benzoylhydrazone (H2L¹) reacts with copper(II) acetate in ethanol in the presence of pyridine-4-carboxylic acid (isonicotinic acid, HL²) to green-[Cu(HL¹)(L²)]·H2O·C2H5OH (1) and brown-[Cu(L¹)(HL²)] (2) complexes which crystallize as concomitant tautomers where either the mono-anion (HL¹)⁻ or di-anion (L¹)²â» of the Schiff base and simultaneously the pyridine-carboxylate (L²)⁻ or the acid (HL²) (both through the pyridine nitrogen atom) function as ligands. The square-planar molecular copper(II) complexes differ in only a localized proton position either on the amide nitrogen of the hydrazone Schiff base in 1 or on the carboxyl group of the isonicotin ligand in 2. The proportion of the tautomeric forms in the crystalline solid-state can be controlled over a wide range from 1:2 = 95 : 5 to ∼2 : 98 by increasing the solution concentration. UV/Vis spectral studies show both tautomers to be kinetically stable (inert), that is, with no apparent tautomerization, in acetonitrile solution. The UB3LYP/6-31+G* level optimized structures of the two complexes are in close agreement with experimental findings. The solid-state structures feature 1D hydrogen-bonded chain from charge-assisted O((-))H-N and O-H((-))N hydrogen bonding in 1 and 2, respectively. In 1 pyridine-4-carboxylate also assumes a metal-bridging action by coordinating a weakly bound carboxylate group as a fifth ligand to a Cu axial site. Neighboring chains in 1 and 2 are connected by strong π-stacking interactions involving also the five- and six-membered, presumably metalloaromatic Cu-chelate rings.