9 research outputs found
Sol-gel routes towards magnetic nanocomposites with tailored microwave absorption
Communication to : Materials research society fall-meeting-V-nanophase and nanomaterials, Boston, MA (USA), December 2-6, 1996SIGLEAvailable from INIST (FR), Document Supply Serviceunder shelf-number : 22419, issue : a.1997 n.25 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc
How to tailor the porous structure of alumina and aluminosilicate gels and glasses
SIGLEAvailable at INIST (FR), Document Supply Service, under shelf-number : 22419, issue : a.1996 n.35 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc
Sintering of alumina and mullites prepared by slow hydrolysis of alkoxides : the role of the protonic species and of pore topology
1 : Communication at 6th workshop on glasses and ceramics from gels, Sevilla (Spain)ndia), January 10-26, 1990. 2 : Journal of non crystalline solid M203A 202CSIGLEAvailable at INIST (FR), Document Supply Service, under shelf-number : 22419, issue : a.1991 n.206 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc
The structural and dynamics neutron study of proton conductors: Difficulties and improvement procedures in protonated perovskite
With the expected development of Hydrogen as energy vector, there is a great impetus on the study of thermally stable proton conductors, the core of fuel cells, electrolysers and potential CO2 converters. Prior to a successful industrial application one should first well determine their extremely complex physical and chemical behaviour related to the unique character of the proton. The difficulties in comprehension of the nature of mobile protonic species, their location (especially the differentiation between bulk and surface species) as well as local and long range dynamics are different as a function of the hydration level: i) in hydrates the number of protons not really involved in the conduction is much larger than that of protonic conducting species, ii) in non-hydrated materials, the total amount of conducting protons can be very small, as dopants in semiconductors, and similar to that arising from surface water and physisorbed protonic moieties. The attempts and difficulties to locate and identify the protonic species and their dynamics using the neutron techniques are discussed in the light of representative examples, with emphasis on proton conducting perovskites