Objectif The aims of this programme are the synthesis, spectroscopic, electrical and structural characterisation of thermostable protonic conductors, which are potential solid electrolytes for various electrochemical devices operating at between 100 and 300 C. The electrolytes that will be developed in the present project are anhydrous, and owe their transport properties to the presence of particularly labile protons and particular structural characteristics incorporating a disordered hydrogen bond network. MHXO4, M3H(XO4)2, M5H3(XO4)4.H2O and MH2YO4, (M = NH4, K, Rb, Cs; X = S, Se; Y = P, As, are characterised by a number of temperature dependent phase transitions, the most important in the present context being the transition to the superprotonic phase, which occurs at temperatures as low as 27 C [(NH4)3H(SeO4)2], but can be as high as ca.170 C [RbHSeO4, Cs3H(SeO4)2]. Superprotonic conductivity (10-3 - 10-1 Scm-1) is then observed up to the melting temperature (< 330 C). During the course of the project, the range of known acid salts in this family will be extended, in particular to new phases M4H2(AO4)3 and M5H3(XO4)4 and to mixed metal salts based on these stoichiometries: (M1-yMy)H(X1-xXxO4) and (M1-yMy)H(X1-xXxO4)4, with the aim of decreasing the superionic phase transition temperature (superprotonic conduction at or below room temperature), of further improving the protonic conduction properties up to the melting temperature and ameliorating the chemical stability. New ceramics based on (M1-yMy)H(X1-xXxO4) and Pb3(PO4)2 or Na(Bi/Ta)(Mo/W)O4 will also be synthesised in order to improve the mechanical properties and chemical stability. Their use in electrochemical devices operating at ambient or at medium temperature could then be envisaged. Programme(s) IC-INTAS - International Association for the promotion of cooperation with scientists from the independent states of the former Soviet Union (INTAS), 1993- Thème(s) 32 - Analytical and Physical Chemistry Appel à propositions Data not available Régime de financement Data not available Coordinateur Centre National de la Recherche Scientifique Contribution de l’UE Aucune donnée Adresse Place Eugène Bataillon 2 34095 Montpellier France Voir sur la carte Coût total Aucune donnée Participants (4) Trier par ordre alphabétique Trier par contribution de l’UE Tout développer Tout réduire Dnepropetrovsk State University Ukraine Contribution de l’UE Aucune donnée Adresse 320625 Dnepropetrovsk Voir sur la carte Coût total Aucune donnée Institute of Agriculture Kazakhstan Contribution de l’UE Aucune donnée Adresse 458015 Kustanaii Voir sur la carte Coût total Aucune donnée Russian Academy of Sciences Russie Contribution de l’UE Aucune donnée Adresse 117333 Moscow Voir sur la carte Coût total Aucune donnée UNIVERSITY OF EXETER Royaume-Uni Contribution de l’UE Aucune donnée Adresse STOCKER ROAD EX4 4QD EXETER Voir sur la carte Coût total Aucune donnée