New multifunctional sulfonato-containing metal phosphonates proton conductors

Anchoring of acidic functional groups to organic linkers acting as ligands in metal phosphonates has been demonstrate to be a valid strategy to develop new proton conductor materials, which exhibit tunable properties and are potentially applicable to proton exchange membranes, such as those used in PEMFCs [1,2]. In this work, the structural and proton conductivity properties of several families of divalent and trivalent metal amino-sulfophosphonates are presented. The chosen ligand, (H2O3PCH2)2-N-(CH2)2-SO3H, was reacted with the appropriate metal salt using highthrough-put screening and/or microwave-assisted synthesis. Different crystal structures haven been solved displaying a variety of metal ligand coordination modes, in whose frameworks acidic groups contribute to create strong H-bond networks; together with lattice and bound water molecules. Proton conductivity values oscillate between 10-4 and 10-2 S.cm-1, at 80 ºC and 95 % relative humidity, most of them showing activation energies characteristic of a Grotthuss-type proton transport mechanism.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. MINECO: MAT2016-77648-R Junta de Andalucía: P-12-FQM-1656 y FQM-11

Proton conductivity and luminiscence properties of lanthanide aminotriphosphonates

Metal phosphonates are multifunctional solids with tunable properties, such as internal H-bond networks, and high chemical and thermal stability [1]. In the present work, we describe the synthesis, structural characterization, luminescent properties and proton conduction performance of a new family of isostructural cationic compounds with general formula [Ln(H4NMP)(H2O)2]Cl·2H2O [Ln = La3+, Pr3+, Sm3+, Gd3+, Tb3+, Dy3+, Ho3+, H6NMP = nitrilotris(methylphosphonic acid)]. These solids are formed by positively charge layers, which consist of isolated LnO8 polyhedra and bridge chelating NMP2- ligands, held apart by chloride ions and water molecules. This arrangement result in extended interlayer hydrogen networks with possible proton transfer pathways. The proton conductivity of Gd3+ sample, selected as prototype of the series, was measured. In the range between range 25º and 80 ºC, the conductivity increase with the temperature up to a maximum value of 3.10-4 S·cm-1, at relative humidity of 95 %. The activation energy obtained from the Arrhenius plot (Figure 1) is in the range corresponding to a Grotthuss transfer mechanism.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. FQM-1656; MAT2013-41836-R

Luminescent and Proton Conducting Lanthanide Coordination Networks Based On a Zwitterionic Tripodal Triphosphonate

The synthesis, structural characterization, luminescence properties, and proton conduction performance of a new family of isostructural cationic 2D layered compounds are reported. These have the general formula [Ln(H4NMP)- (H2O)2]Cl·2H2O [Ln = La3+, Pr3+, Sm3+, Eu3+, Gd3+, Tb3+, Dy3+, Ho3+, H6NMP = nitrilotris(methylphosphonic acid)], and contain Cl− as the counterion. In the case of Ce3+, a 1D derivative, [Ce2(H3NMP)2(H2O)4]·4.5H2O, isostructural with the known lanthanum compound has been isolated by simply crystallization at room temperature. The octa-coordinated environment of Ln3+ in 2D compounds is composed by six oxygen atoms from three different ligands and two oxygens from each bound water. Two of the three phosphonate groups act as both chelating and bridging linkers, while the third phosphonate group acts solely as a bridging moiety. The materials are stable at low relative humidity at less at 170 °C. However, at high relative humidity transform to other chloride-free phases, including the 1D structure. The proton conductivity of the 1D materials varies in a wide range, the highest values corresponding to the La derivative (σ ≈ 2 × 10−3 S·cm−1 at RH 95% and 80 °C). A lower proton conductivity, 3 × 10−4 S·cm−1, was measured for [Gd(H4NMP)(H2O)2]Cl·2H2O at 80 °C, which remains stable under the work conditions used. Absorption and luminescence spectra were recorded for selected [Ln(H4NMP)(H2O)2]Cl·2H2O compounds. In all of them, the observed transitions are attributed solely to f−f transitions of the lanthanide ions present, as the H4NMP2− organic group has no measurable absorption or luminescence properties.Proyecto nacional MAT2013-41836-R (MINECO) y Proyecto de la Junta de Andalucía P12-FQM-165

Adherence to chronic medication in older populations: application of a common protocol among three European cohorts

Purpose: The purpose of this study was to evaluate and compare medication adherence to chronic therapies in older populations across different regions in Europe. Methods: This explorative study applied a harmonized method of data extraction and analysis from pharmacy claims databases of three European countries to compare medication adherence at a cross-country level. Data were obtained for the period between January 1, 2010, and December 31, 2011. Patients (aged >= 65 years) who newly initiated to oral antidiabetics, antihyperlipidemics, or antiosteoporotics were identified and followed for over a 12-month period. Main outcome measures were medication adherence (medication possession ratio, [MPR]; implementation) and persistence on index treatment. All country-specific data sets were prepared by employing a common data input model. Outcome measures were calculated for each country and pooled using random effect models. Results: In total, 39, 186 new users were analyzed. In pooled data from the three countries, suboptimal implementation (MPR <80%) was 52.45% (95% CI: 33.43-70.79) for antihyperlipidemics, 61.35% (95% CI: 52.83-69.22) for antiosteoporotics, and 30.33% (95% CI: 25.53-35.60) for oral antidiabetics. Similarly, rates of non-persistence (discontinuation) were 55.63% (95% CI: 35.24-74.29) for antihyperlipidemics, 60.24% (95% CI: 45.35-73.46) for antiosteoporotics, and 46.80% (95% CI: 36.40-57.4) for oral antidiabetics. Conclusion: Medication adherence was suboptimal with >50% of older people non-adherent to antihyperlipidemics and antiosteoporotics in the three European cohorts. However, the degree of variability in adherence rates among the three countries was high. A harmonized method of data extraction and analysis across health-related database in Europe is useful to compare medication-taking behavior at a cross-country level

From light to heavy alkali metal tetraphosphonates (M = Li, Na, K, Rb, Cs): cation size-induced structural diversity and waterfacilitated proton conductivity

A family of alkali metal-based frameworks containing the tetraphosphonate ligand hexamethylenediamine- N,N,N′,N′-tetrakisIJmethylenephosphonic acid), HDTMP, is reported. A cation size-induced structural diversity, from monodimensional solids (Li+ and Na+) through layered (K+) to pillared-layered (Rb+ and Cs+) structures, was found. The proton conductivity properties of the Li compounds (hydrated and dehydrated) are reported and the influence of dehydration/rehydration processes in enhancing proton transfer processes is highlighted. Reversible changes in the dimensionality occurred upon full dehydration/rehydration with minor rearrangements in the framework, implying variations in the Li+–ligand connectivity but preserving the tetracoordination of the metal ion. The reversibly dehydrated–rehydrated sample displayed the highest proton conductivity (5 × 10−3 S cm−1 at 80 °C and 95% RH), a behavior attributed to reversible formation/ reformation of P–OIJH)–Li bonds that, in turn, provoked changes in the acidity of acid groups and water mobility in the temperature range of impedance measurements.Proyecto MAT2016-77648-R del ministerio y proyecto P12-FQM-1656 de la Junta de Andalucía Ministerio de Economía y Competitividad por el contrato Ramon y Cajal (RyC2015-17870)

Phase Transformation Dynamics in Sulfate-Loaded Lanthanide Triphosphonates. Proton Conductivity and Application as Fillers in PEMFCs

Phase transformation dynamics and proton conduction properties are reported for cationic layer-featured coordination polymers derived from the combination of lanthanide ions (Ln3+) with nitrilo-tris(methylenephosphonic acid) (H6NMP) in the presence of sulfate ions. Two families of materials are isolated and structurally characterized, i.e., [Ln2(H4NMP)2(H2O)4](HSO4)2·nH2O (Ln = Pr, Nd, Sm, Eu, Gd, Tb, Er, Yb; n = 4−5, Series I) and [Ln(H5NMP)]SO4· 2H2O (Ln = Pr, Nd, Eu, Gd, Tb; Series II). Eu/Tb bimetallic solid solutions are also prepared for photoluminescence studies. Members of families I and II display high proton conductivity (10−3 and 10−2 S·cm−1 at 80 °C and 95% relative humidity) and are studied as fillers for Nafion-based composite membranes in PEMFCs, under operating conditions. Composite membranes exhibit higher power and current densities than the pristine Nafion membrane working in the range of 70−90 °C and 100% relative humidity and with similar proton conductivity.Proyectos de Ministero de Ciencia e Innovación MAT2016-77648-R (MICINN/FEDER); PID2019-110249RB-I00 (MICINN/FEDER) y la Junta de Andalucía (FQM113). Funding for open access change: Universidad de Málaga/ CBU

New multifuncional divalent metal-coordinated sulfophosphonates: structures and proton conductivities

Metal phosphonate-based coordination polymers are structurally versatile multifunctional compounds that may contain a number of acidic groups such as P-OH; SO3H, COOH, N+-H…These features result in formation of extended H-bond networks and confer proton conducting properties. In this work, the crystal structures resulting from the combination of the amino-sulfophosphonate ligand (H2O3PCH2)2-N-(CH2)2-SO3H with different divalent metal ion, are reported. Optimal synthesis conditions were implemented by microwave methodology and high through-put screening. For cupper derivatives, single-crystal data were employed. While for Mn(II) derivative the crystal structure was solved ab initio from synchrotron X-ray powder diffraction data. The arrangement of the sulfonic groups determines a wide variety of metal-ligand coordination modes and the creation of efficient hydrogen bonding networks for proton transport, as has been observed for other lanthanide derivatives. For copper derivatives the presence of an auxiliary ligand (1,10-phenanthroline, 2,2’-bipyridine or 4,4’-bipyridine) were required to obtain a crystalline compound. As a consequence of this structural variability, different H bond networks can be generated leading to a wide range of proton conductivity values