2026-06-05T17:26:28Zhttps://riuma.uma.es/rest/oai/request

oai:riuma.uma.es:10630/209862026-02-03T11:36:49Zcom_10630_2254col_10630_37953

00925njm 22002777a 4500 dc Pérez-Colodrero, Rosario Mercedes author Salcedo, Inés R. author Bazaga-García, Montse author Milla-Pérez, Diego F. author Durán-Martín, Jonatan D. author Ramírez-Losilla, Enrique author Moreno-Real, Laureano author Rius, Jordi author García-Aranda, Miguel Ángel author Demadis, Konstantinos D. author Olivera-Pastor, Pascual author Cabeza-Díaz, Aurelio author 2017 The structural variability of two series of Mg2+- and Zn2+- 2-hydroxyphosphonoacetates have been studied in the range of 25–80 °C and 95 % relative humidity in order to correlate the structure with the proton conductivity properties. In addition to selected previously reported 1D, 2D and 3D materials, a new compound, KZn6(OOCCH(OH)PO3)4(OH)·5H2O (KZn6-HPAA-3D), has been prepared and thoroughly characterized. The crystal structure of this solid, solved ab initio from synchrotron X-ray powder diffraction data, consists of a negatively charged 3D framework with K+ ions, as compensating counterions. It also contains water molecules filling the cavities in contrast to the potassium-free 3D anhydrous NH4Zn(OOCCH(OH)PO3) (NH4Zn-HPAA-3D). In the range of temperature studied, the 1D materials exhibit a 1D → 2D solid-state transition. At 80 °C and 95 % RH, the 2D solids show moderate proton conductivities, between 2.1 × 10 − 5 S·cm − 1 and 6.7 × 10− 5 S·cm− 1. The proton conductivity is slightly increased by ammonia adsorption up to 2.6 × 10 − 4 S·cm − 1, although no ammonia intercalation was observed. As synthesized KZn6-HPAA-3D exhibits a low proton conductivity, 1.6 × 10− 6 S·cm− 1, attributed to the basic character of the framework and a low mobility of water molecules. However, this solid transforms to the 2D phase, Zn(OOCCH(OH)PO3H)·2H2O, upon exposure to dry HCl(g), which enhances the proton conductivity with respect to the as-synthesized 2D material (4.5 × 10− 4 S·cm− 1). On the other hand, NH4Zn-HPAA-3D exhibited a higher proton conductivity, 1.4 × 10− 4 S·cm− 1, than the K+ analog. Colodrero, R., Salcedo, I., Bazaga-García, M., Milla-Pérez, D., Durán-Martín, J., Losilla, E., Moreno-Real, L., Rius, J., Aranda, M., Demadis, K., Olivera-Pastor, P., & Cabeza, A. (2017). Structural variability in M2+ 2-hydroxyphosphonoacetate moderate proton conductors. Pure and Applied Chemistry, 89(1), 75–87. https://doi.org/10.1515/pac-2016-1003 https://hdl.handle.net/10630/20986 10.1515/pac-2016-1003 Conductividad eléctrica Semimetales Polímeros organometálicos Química del estado sólido Structural variability in M2+ 2-hydroxyphosphonoacetate moderate proton conductors