RT Conference Proceedings
T1 Proton conductivity properties of tin(IV) N,Nbis( phosphonomethyl)glycine phosphonates and their pyrophosphate-based derivatives
A1 Cañamero-Cebrián, Fernando
A1 Galindo-Larrahondo, Jorge Armando
A1 Ramírez-Losilla, Enrique
A1 Pérez-Colodrero, Rosario Mercedes
A1 Bazaga-García, Montse
A1 Olivera-Pastor, Pascual
A1 Cabeza-Díaz, Aurelio
K1 Compuestos organofosforados
K1 Conductividad eléctrica
AB Metal phosphonates (MPs), a subclass of coordination polymers, are distinguished bytheir acidic functional groups, such as –P–OH, –SO₃H, and –COOH. Combined with theirchemical and thermal stability, commercial availability, and synthetic versatility, thesefeatures make MPs particularly appealing for fuel cell applications. They have shownremarkable potential not only as proton-conductive materials for proton exchangemembrane fuel cells (PEMFCs), but also as precursors to metal diphosphate-based proton conductors suitable for intermediate-temperature fuel cells (ITFCs), between 100 and 300 ºC.In this work, we present the synthesis and characterization of a novel family ofamorphous tin(IV) phosphonates, Sn[(COOH-CH2)N((CH2-PO(OH)2)2](OH)0.8 (H₂O)3(SnBPMGLY); doped with variable amounts (0.1 - 0.3) of Al3+ or Mg2+ ions. Both, undopedand doped materials, were subjected to pyrolytic treatment at 750 °C in air, resultingpredominantly in tin(IV) pyrophosphates with slight compositional variations.All materials were thoroughly characterized with respect to their proton conductionproperties. The as-synthesized undoped material, SnBPMGLY, exhibited notableconductivity, reaching up to 5.05 × 10⁻⁴ S·cm-1, at 90 °C and 95% relative humidity (RH).After pyrolysis, the resulting tin pyrophosphates showed higher proton conductivities, withvalues up to 1.3 × 10⁻² S·cm-1 in the case of Sn0.8Al0.2BPMGLY Δ750 ºC under the same conditions. The low activation energy values (E < 0.35 eV) determined from the Arrhenius aplots suggest a water-mediated Grotthuss proton transfer mechanism. Current efforts arefocused on evaluating the performance of these pyrolyzed materials at intermediatetemperature (125–300 °C) under high vapor pressure conditions.
YR 2025
FD 2025
LK https://hdl.handle.net/10630/39828
UL https://hdl.handle.net/10630/39828
LA eng
NO University of Malaga under Plan Propio de Investigación
NO Spanish Ministry of Economy, Industry and Competitiveness
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 5 may 2026