High-stress study of bioinspired multifunctional PEDOT:PSS/nanoclay nanocomposites using AFM, SEM and numerical simulation

• Alfredo J. Diaz,
• Hanaul Noh,
• Tobias Meier and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2017, 8, 2069–2082, doi:10.3762/bjnano.8.207

• the AFM probe diameter. No pressure-induced changes in conductivity were observed in the clay-free polymer either. Keywords: biomimetics; conductive AFM; conductive nanocomposites; contact-resonance force microscopy; multifrequency AFM; transparent coatings; Introduction Bioinspired material designs

• to produce artificial nacre is usually based on a self-assembly process involving clay nanosheets (nanoclays) and polymers. In general, the dispersed polymer-coated nanoclays naturally organize by liquid removal, leading to an organic-inorganic multi-layered assembly, the so-called brick-and-mortar

• 768642, abbreviated as PPSS), a high-conductivity grade polymer, in 1.0 wt % solution in water was used as received. The core/shell nanoplatelets were prepared by slowly adding the nanoclay dispersion to a stirred polymer solution with a 33:67 (clay/polymer) weight ratio, which was further stirred for

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

• Marwa Akkari,
• Pilar Aranda,
• Abdessalem Ben Haj Amara and
• Eduardo Ruiz-Hitzky

Beilstein J. Nanotechnol. 2016, 7, 1971–1982, doi:10.3762/bjnano.7.188

• Bizerte, University of Carthage, 7021 Zarzouna, Tunisia 10.3762/bjnano.7.188 Abstract In this study, ZnO/SiO2-clay heterostructures were successfully synthesized by a facile two-step process applied to two types of clays: montmorillonite layered silicate and sepiolite microfibrous clay mineral. In the

• ultrasound irradiation to the silica–organoclay hybrid heterostructures dispersed in 2-propanol, and finally, the resulting solids were calcinated to eliminate the organic matter and to produce ZnO nanoparticles (NP) homogeneously assembled to the clay–SiO2 framework. In the case of montmorillonite the

• resulting materials were identified as delaminated clays of ZnO/SiO2-clay composition, whereas for sepiolite, the resulting heterostructure is constituted by the assembling of ZnO NP to the sepiolite–silica substrate only affecting the external surface of the clay. The structural and morphological features

Controlled supramolecular structure of guanosine monophosphate in the interlayer space of layered double hydroxide

• Gyeong-Hyeon Gwak,
• Istvan Kocsis,
• Yves-Marie Legrand,
• Mihail Barboiu and
• Jae-Min Oh

Beilstein J. Nanotechnol. 2016, 7, 1928–1935, doi:10.3762/bjnano.7.184

• nanocomposites [5]. Post-synthetic thermal treatment resulted in polymerization of amino acids in LDH. It was also reported that amino acids such as arginine and glutamate were polymerized via peptidic condensation both on the surface and in the interlayer space of clay [6]. In that literature, peptidic

• condensation of amino acids was determined to favor heteropeptide rather than homopeptide. Besides polymerization of amino acids, it was reported that abiotic oligomerization of RNA nucleotides was catalyzed by montmorillonite clay [7]. In the presence of clay, the length of polymerized RNA oligonucleotides

• was three times longer than without clay. Among biological molecules, guanosine derivatives are known to have various supramolecular assembly routes through intermolecular interactions. For instance, telomere in chromosome consists of stacks of guanosine quartets (G4), in which four guanosines are

Effective intercalation of zein into Na-montmorillonite: role of the protein components and use of the developed biointerfaces

• Ana C. S. Alcântara,
• Margarita Darder,
• Pilar Aranda and
• Eduardo Ruiz-Hitzky

Beilstein J. Nanotechnol. 2016, 7, 1772–1782, doi:10.3762/bjnano.7.170

• , intercalate into montmorillonite and other smectite clay minerals, producing biohybrid materials [2]. Montmorillonite is a 2:1 phyllosilicate characterized by a colloidal particle size, high specific surface area and large cation exchange capacity (CEC) around 70–100 milliequivalents/100 g of clay

• intercalation of gelatin into montmorillonite [4], other biohybrids also based on the assembly of smectite clays and proteins (e.g., bovine serum albumin, gelatin, casein or soy) have been vastly studied [5][6][7][8][9][10]. However, protein adsorption on montmorillonite clay can be considered a complex process

• hydrophobic residues may be also a key factor in order to achieve their intercalation in montmorillonite [11][12]. Thus, depending on the type of protein involved, it is possible to obtain different interaction mechanisms between the clay and the biomacromolecule, generating the need to investigate possible

Green synthesis, characterization and catalytic activity of natural bentonite-supported copper nanoparticles for the solvent-free synthesis of 1-substituted 1H-1,2,3,4-tetrazoles and reduction of 4-nitrophenol

• Akbar Rostami-Vartooni,
• Mohammad Alizadeh and
• Mojtaba Bagherzadeh

Beilstein J. Nanotechnol. 2015, 6, 2300–2309, doi:10.3762/bjnano.6.236

• The development of new methodologies for the preparation of heterogeneous catalysts is of great interest in organic synthesis [1]. Metal nanoparticles immobilized on supports such as carbon, zeolites, clay, metal oxides, graphene, etc., have been successfully applied as heterogeneous catalysts due to

• distributed and stable metal NPs. In recent decades, the use of natural bentonites has been studied due to their high specific surface area, low cost, ordered structure, thermal stability, high safety, high exchange capacity and intercalation abilities [8]. Smectites are major clay minerals in bentonite with

• bentonite (Figure 3b) are shown in Figure 3. The XRD pattern in Figure 3a reveals that the principal constituents of the employed natural clay are montmorillonite (M) and quartz (Q), where the characteristic peaks located at 2θ = 19.84, 34.80, and 61.84° were indexed to (020), (130), and (060) planes of

Biopolymer colloids for controlling and templating inorganic synthesis

• Laura C. Preiss,
• Katharina Landfester and
• Rafael Muñoz-Espí

Beilstein J. Nanotechnol. 2014, 5, 2129–2138, doi:10.3762/bjnano.5.222

• sol, followed by a gelation process, porous hybrid structures can be obtained. Starting from a colloidal suspension of laponite particles, Shi et al. [4] reported the preparation of a nanocomposite matrix of chitosan and clay that was applied as a glucose biosensor. Very recently, da Costa Neto et al

Surface functionalization of aluminosilicate nanotubes with organic molecules

• Wei Ma,
• Weng On Yah,
• Hideyuki Otsuka and
• Atsushi Takahara

Beilstein J. Nanotechnol. 2012, 3, 82–100, doi:10.3762/bjnano.3.10

• most molecules. On the contrary, clay nanotubes present a reactive surface for numerous coupling agents and are emerging as useful structural units for many kinds of nanohybrid materials [7][8][9][10][11]. For the assembly of organic molecules on an inorganic surface, most work has been carried out

Twofold role of calcined hydrotalcites in the degradation of methyl parathion pesticide

• Alvaro Sampieri,
• Geolar Fetter,
• María Elena Villafuerte-Castrejon,
• Adriana Tejeda-Cruz and
• Pedro Bosch

Beilstein J. Nanotechnol. 2011, 2, 99–103, doi:10.3762/bjnano.2.11

• sorbed on a bentonite (cationic clay) [6][7][8]. Moreover, the bentonite sorption capacity may be increased if the clay is exchanged with cetyltrimethylammonium bromide (CTAB). Indeed, the hydrophobic character of the pesticide and the organoclay enhances the retention through two mechanisms; either MP

• may be reduced directly to p-NP (degradation) or via an intermediate molecule (isomerization). At pH 9 or 10, the second mechanism is favored (65%) due to the basic catalytic features of the clay hydroxyl ions (OH). Although MP can decompose to give simple molecules, such as SO2, CO2, CO and NO2