caa a22 4500 60619505X CHVBK 20210128100917.0 cr unu---uuuuu 210128e20151201xx s 000 0 eng 10.1007/s10934-015-0042-6 doi (NATIONALLICENCE)springer-10.1007/s10934-015-0042-6 Bizi Mohamed BRGM, French Geological Survey, 3 Avenue C. Guillemin, 45060, Orléans Cedex 2, France aut The structure and textural heterogeneity of single- and double-walled aluminogermanate imogolites [Elektronische Daten] [Mohamed Bizi] This work studies the combined use of XRD, AFM and gas adsorption to determine the structure and textural heterogeneity of two Ge-imogolite nanotubes, one single-walled and another double-walled (<100nm). In XRD, the indexation of lines is broadened, reflection lines 003, 004, 005 and 006 are identified and the signature of the presence of a double wall is revealed on the diffractogram. Contrary to current assumptions concerning these two products, both AFM and adsorption/desorption of N2 at 77K and of CO2 at 273K show that these two imogolites are polydisperse and heterogeneous in terms of length and inner and outer diameter. An analysis of adsorption clearly shows that N2 is limited to the characterization of porosities between 1 and 50nm and that CO2 is better-suited to the analysis of ultramicropores (<1nm). The specific surfaces of micropores estimated with N2 are greatly underestimated. The application of the Dubinin-Astakhov model shows that the two imogolites have very extensive microporous specific surfaces whose structure is heterogeneous and accessible to exchanges. Springer Science+Business Media New York, 2015 Aluminogermanates nationallicence Double-walled nationallicence Imogolite nationallicence Micropore nationallicence Nanotubes nationallicence Pore size nationallicence Journal of Porous Materials Springer US; http://www.springer-ny.com 22/6(2015-12-01), 1589-1597 1380-2224 22:6<1589 2015 22 10934 https://doi.org/10.1007/s10934-015-0042-6 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10934-015-0042-6 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Bizi Mohamed BRGM, French Geological Survey, 3 Avenue C. Guillemin, 45060, Orléans Cedex 2, France aut NATIONALLICENCE 773 0- Journal of Porous Materials Springer US; http://www.springer-ny.com 22/6(2015-12-01), 1589-1597 1380-2224 22:6<1589 2015 22 10934