title: Evidence of double-walled Al-Ge imogolite-like nanotubes. a cryo-TEM and SAXS investigation.
abstract: It has been recently discovered that the synthesis of Al-Ge imogolite-like nanotubes is possible at high concentration. Despite this initial success, the structure of these Al-Ge imogolite-like nanotubes remains not completely understood. Using high resolution cryo-TEM and Small Angle X-ray Scattering, we unravel their mesoscale structure in two contrasted situations. On the one hand, Al-Ge imogolite nanotubes synthesized at 0.25 M are double-walled nanotubes of 4.0 +/- 0.1 nm with an inner tube of 2.4 +/- 0.1 nm. Moreover, SAXS data also suggest that the two concentric tubes have an equal length and identical wall structure. On the other hand, at higher concentration (0.5M), both SAXS and cryo-TEM data confirm the formation of single-walled nanotubes of 3.5 +/- 0.15 nm. Infrared spectroscopy confirms the imogolite structure of the tubes. This is the first evidence of any double-walled imogolite or imogolite-like nanotubes likely to renew interest in these materials and associated potential applications.
authors.affiliation: CEA, IRAMIS, Laboratoire Interdisciplinaire sur l'Organisation Nanométrique et Supramoléculaire 91191 Gif-sur-Yvette, France.
authors.forename: Perrine
authors.initials: P
authors.lastname: Maillet
authors.forename: Clément
authors.initials: C
authors.lastname: Levard
authors.forename: Eric
authors.initials: E
authors.lastname: Larquet
authors.forename: Clarisse
authors.initials: C
authors.lastname: Mariet
authors.forename: Olivier
authors.initials: O
authors.lastname: Spalla
authors.forename: Nicolas
authors.initials: N
authors.lastname: Menguy
authors.forename: Armand
authors.initials: A
authors.lastname: Masion
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Doelsch
authors.forename: Jérôme
authors.initials: J
authors.lastname: Rose
authors.forename: Antoine
authors.initials: A
authors.lastname: Thill