Surfactant-modifications of Na+-beidellite for the preparation of TiO2-Bd supported photocatalysts: I-organobeidellite precursor for nanocomposites

Abstract

International audienceThis study aims at determining suitable conditions for the preparation of the best organobeidellite starting material used for the development of efficient mesoporous TiO2 supported beidellite (Bd) photocatalysts. For this purpose, organo-modifications of natural Bd from Agadir Basin (Morocco) were achieved. The influence of (i) the length of alkyl chains Cn (n = 8, 12, 14 and 16) of n-alkyl ammonium surfactants CH3(CH2)n-1NH3+ and (ii) the amount of C16 surfactant ranging from 1 to 5 times the smectite (Sm) cation exchange capacity (CEC) on the structure of organo- Bd was studied. XRD, TEM, TG-DTA and FTIR results are consistent with the intercalation of cationic surfactants species in Bd interlayer spaces according to different conformations yielding to their expansion. The interlayer expansion magnitude increased both with the length of alkyl chain and the amount of C16 surfactant. Organomodification with increasing surfactant load beyond 1CEC besides yielded to the adsorption of increasing excess on external surfaces of Bd particles. These controlled structural modifications will be used further in the functionalization of this Bd by TiO2 nanoparticles to produce efficient supported TiO2-Bd photocatalysts

Highly thermostable and crystalline poly(butylene adipate) bionanocomposites prepared by in situ polycondensation with organically modified Moroccan beidellite clay

“…The broadness of the reflection peaks can be explained by the heterogeneity of charge density in BDT layers, leading to different configurations of CTA in the interlayer spaces . Based on the CTA extended length of 25.3 Å, the different interlayer spacings in 1CTA‐BDT, 3CTA‐BDT and 5CTA‐BDT may be assigned to tilted paraffin monolayer and bilayer CTA configurations (Table ) …”

“…The organo‐modified BDT clay used in this study was prepared by the cation exchange reaction between Na‐BDT and CTA . To investigate the influence of CTA concentration on the actual loading and mode of insertion within the Na‐BDT interlayer spaces, the cation exchange was carried on at different CTA/Na‐BDT ratios, that is, by using 1, 3 and 5 equivalent ratios of CTA to the CEC of Na‐BDT.…”

Organoclay hybrid materials as precursors of porous ZnO/silica-clay heterostructures for photocatalytic applications

“…The more common silica sources used to prepare them are tetraethoxysilane (TEOS) and tetramethoxysilane (TMOS) although this methodology may involve the use of other alkoxysilanes as well as diverse metal alkoxides [14]. The influence of the surfactant incorporated into the organoclay on the characteristics of the obtained materials has been pointed out recently [15–16]. The methodology has been also applied to organoclays derived from fibrous clays (e.g., sepiolite) in which the presence of the surfactant at the external surface results in the formation of silica NP of diverse characteristics depending on the nature of both, silane precursor and surfactant present at the organic–inorganic interface [17].…”

Dielectric and interfacial properties investigation of poly(acrylonitrile‐co‐2,2,2‐trifluoroethyl methacrylate) copolymer/organomodified beidellite clay nanocomposites

“…The organomodified beidellite clay used in this study was prepared by the cation exchange reaction between beidellite (Na‐BDT) and cetyltrimethylammonium bromide (CTA) 23 . The cation exchange was carried on CTA/Na‐BDT ratio by using onr equivalent ratio of CTA to the cation exchange capacity (CEC) of Na‐BDT.…”