Metal phosphonate-carboxylate compounds represent a promising class of materials for proton conduction applications. This study investigates the structural, thermal, and proton conduction properties of three groups of lanthanide-based compounds derived from 5-(dihydroxyphosphoryl)isophthalic acid (PiPhtA). The crystal structures, solved from X-ray powder diffraction data, reveal that groups , Ln[OP-CH(COO)(COOH)(HO)] (Ln = La, Pr), and , Ln{[OP-CH(COO)(COOH)](HO)}·2HO (Ln = La, Pr, Eu), exhibit three-dimensional frameworks, while group , Ln[OP-CH(COO)(COOH)(HO)] (Ln = Yb), adopts a layered structure with unbonded carboxylic groups oriented toward the interlayer region.
View Article and Find Full Text PDFWipe wastes have been used as a cellulosic source to synthesize biochars. Prior to the synthesis of the adsorbents by the pyrolysis of wipes wastes, this waste was treated to remove the pathogenic agents. Then, the wipe wastes were pyrolyzed between 500 and 900 °C to obtain biochars, whose microporosity increased proportionally to the pyrolysis temperature, achieving a maximum CO-adsorption uptake of 2.
View Article and Find Full Text PDFThree chitosans with different morphologies have been used (commercial chitosan powder, chitosan in film form and chitosan in globular form synthesized by the freeze-dried method) for the synthesis of biochars. The pyrolytic treatment has revealed that the biochar synthesized from the chitosan formed by the freeze-dried method reaches the highest CO-adsorption capacity (4.11 mmol/g at 0 °C and a pressure of 1 bar) due to this adsorbent is highly microporous.
View Article and Find Full Text PDFThis work deals with the synthesis and characterization of one-dimensional (1D) imidazole-containing etidronates, [M(ETID)(Im)]·HO (M = Co and Ni; = 0, 1, 3) and [Zn(ETID)(HO)](Im), as well as the corresponding Co/Ni solid solutions, to evaluate their properties as multipurpose materials for energy conversion processes. Depending on the water content, metal ions in the isostructural Co and Ni derivatives are octahedrally coordinated ( = 3) or consist of octahedral together with dimeric trigonal bipyramidal ( = 1) or square pyramidal ( = 0) environments. The imidazole molecule acts as a ligand (Co, Ni derivatives) or charge-compensating protonated species (Zn derivative).
View Article and Find Full Text PDFWe report herein the synthesis, structural characterization and electrocatalytic properties of three new coordination polymers, resulting from the combination of divalent metal (Ca, Cd or Co) salts with (2-carboxyethyl)(phenyl)phosphinic acid. In addition to the usual hydrothermal procedure, the Co derivative could also be prepared by microwave-assisted synthesis, in much shorter times. The crystal structures were solved by ab initio calculations, from powder diffraction data.
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