Imogolite in water: simulating the effects of nanotube curvature on structure and dynamics

Imogolite is a fascinating inorganic nanotube that is found in nature or synthesized in a laboratory. The synthesis process is carried out in liquid media, and leads to the formation of almost monodisperse diameter nanotubes. Here we investigate, employing classical molecular dynamics simulations, the interaction of water and imogolite for nanotubes of several radii. We established that water penetrates the pores of N= 9 and larger nanotubes, and adopts a coaxial arrangement in it. Also, while water molecules can diffuse along the center of the nanotube, the molecules next to the inner imogolite walls have very low mobility. At the outer nanotube wall, an increase of water density is observed, this effect extends up to 1 nm, beyond which water properties are bulk-like. Both phenomena are affected by the imogolite curvature.United States Department of Energy (DOE) National Nuclear Security Administration DE-NA-0003525 Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT) CONICYT FONDECYT 1190662 1160639 11180557 1191353 1190484 United States Department of Defense Air Force Office of Scientific Research (AFOSR) FA9550-16-1-0122 Financiamiento Basal para Centros Cientficos y Tecnologicos de Excelencia CEDENNA AFB180001 Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT) CONICYT PIA/ANILLOS ACT192023 DICYT 041931BR USA1799 Vridei 041931SB_GO NLHPC ECM-0