Hybrid organic-inorganic nanotubes effectively adsorb some organic pollutants in aqueous phase

Inorganic nanotubes with permanent wall polarization as dual photo-reactors for wastewater treatment with simultaneous fuel production

“…[44][45][46][47] Indeed, such methylfunctionalized imogolite nanotubes (Imo-CH3) can capture small organic molecules very efficiently, 48,49 making them a promising material to pre-concentrate organic pollutants from contaminated water. 50 Importantly, this chemical modification of the internal surface does not prevent the formation of an intra-wall electric field. 51 Therefore, the Janus character of Imo-CH3 nanotubes with an hydrophobic internal core and an hydrophilic external surface with strong wall polarization provides a unique opportunity to perform oxidative photo-degradation of encapsulated organic pollutants inside the nanotubes with simultaneous reduction reactions on the external surface.…”

Effect of Polymer Length on the Adsorption onto Aluminogermanate Imogolite Nanotubes

“…hydrophilic or hydrophobic cavities) [9][10][11] and high colloidal stability in aqueous media. [12][13][14] All these properties have led in recent years to a renewed interest in synthetic imogolite-type nanotubes as promising nano-reactors notably for molecular confinement [15][16][17][18] or photocatalytic applications. [19][20][21][22][23] INT offers similar characteristics to those of carbon nanotubes (CNTs) in terms of rigidity, sizes and aspect ratios while retaining transparency and self-organization in highly dilute conditions.…”

“…The external walls consist of gibbsite-like sheets Al­(OH) 3 , while the cavity interface is formed by isolated (SiO 3 )­OH tetrahedron units connected upright to the octahedral vacancies by covalent bonding . Silicon can be replaced by germanium allowing us to increase the diameter of the inner cavity from 1.5 to 3 nm for single-walled INTs. , Furthermore, modifications of the synthesis conditions offer a convenient way for designing innovative INTs with well-defined morphologies (single- or double-walled structures), modular interfaces (e.g., hydrophilic or hydrophobic cavities), − and high colloidal stability in aqueous media. − All these properties have led in recent years to a renewed interest in synthetic imogolite-type nanotubes as promising nanoreactors notably for molecular confinement − or photocatalytic applications. − …”

Termination Effects in Aluminosilicate and Aluminogermanate Imogolite Nanotubes: A Density Functional Theory Study

“…Both sides of the imogolite NTs' cavities can be easily functionalized [25][26][27][28]. The synthetic flexibility of imogolite NTs leads to widely tunable properties, with exciting reports as regards the performance of imogolite NT for chemical separation [17,[20][21][22][23][24]26,29], co-photo-catalyst [30], hybrid nanocomposites [31] and colloidal, liquid-crystal applications [32][33][34][35]. In addition to these examples, the potential range of applicability for AlSi AlGe NTs has been recently expanded via synthesis of Fe-doped imogolite NTs, capable of absorbing visible (and UV) light.…”

“…The present results should accordingly be a useful and timely contribution to research in the field of imogolite NTs, especially in terms of the quantification of the extent to which the electronic properties of the peripheral and innermost regions of imogolite nanotubes can differ, potentially leading to profoundly diverse photo-chemical reactivity. Quantification of the structure and steric hindrance of the terminations of imogolite nanotubes should also be a valuable addition to ongoing research into the potential of this class of materials for nanofluidic and chemical separation applications [17,[20][21][22][23][24]26,27,29], as well as a necessary reference for future research in termination effects for double-walled imogolite nanotubes [51][52][53][54][55]. Last but not least, the present results should also provide a valuable, currently missing, first principles benchmark reference for ongoing work in the development of accurate tight-binding DFT methods [56][57][58] or force fields parameterizations [59][60][61][62] towards the simulation of more extended NT models and time-scales than are practically viable at the DFT level.…”