Cyclodextrin-assisted synthesis of tailored mesoporous silica nanoparticles

• Fuat Topuz and
• Tamer Uyar

Beilstein J. Nanotechnol. 2018, 9, 693–703, doi:10.3762/bjnano.9.64

• . Interestingly, at low CD concentrations, the resultant particles exhibited smooth faces. The mean particle size increased from 139 to 207 nm with the HP-γ-CD content increasing from 0.1 to 0.6% (w/v), while the mean pore size of the respective particles remained nearly stable at 3.20 ± 0.10 nm. Similarly

• the alterations in the pore architecture, which was directed by the self-assembly of β-CD during the particle formation. The pore size and volume of the particles were measured using the Brunauer–Emmett–Teller (BET) method. Figure S6 (Supporting Information File 1) shows the nitrogen adsorption

• –desorption isotherms and the pore size diagrams of MSNs. The pristine MSN sample, which does not have any CD moieties, has a mean pore size of 2.64 nm and a surface area of 1374.25 m2/g. BET analysis of the multifaceted silica particles synthesized with 0.25% (w/v) HP-γ-CD revealed a microporous structure

Anchoring Fe₃O₄ nanoparticles in a reduced graphene oxide aerogel matrix via polydopamine coating

• Błażej Scheibe,
• Radosław Mrówczyński,
• Natalia Michalak,
• Karol Załęski,
• Michał Matczak,
• Mateusz Kempiński,
• Zuzanna Pietralik,
• Mikołaj Lewandowski,
• Stefan Jurga and
• Feliks Stobiecki

Beilstein J. Nanotechnol. 2018, 9, 591–601, doi:10.3762/bjnano.9.55

• micrographs of rGO, rGO-Fe3O4 and rGO-PDA@Fe3O4 aerogels. From the low magnification images one can determine the pore size distribution and observe interconnected 3D network of aerogel-forming rGO structures (Figure 1a–c). At higher magnification, the agglomerates of MNPs are clearly visible (Figure 1e,f

• ). From this figure it can be deduced that the distribution of agglomerated MNPs is homogeneous on both sides of the rGO sheets. Figure 2 presents selected SEM micrographs with marked pore size distribution (Figure 2a) and diameter of MNPs (Figure 2b) in rGO-PDA@Fe3O4 aerogel, as well as TEM micrographs

Ultralight super-hydrophobic carbon aerogels based on cellulose nanofibers/poly(vinyl alcohol)/graphene oxide (CNFs/PVA/GO) for highly effective oil–water separation

• Zhaoyang Xu,
• Huan Zhou,
• Sicong Tan,
• Xiangdong Jiang,
• Weibing Wu,
• Jiangtao Shi and
• Peng Chen

Beilstein J. Nanotechnol. 2018, 9, 508–519, doi:10.3762/bjnano.9.49

• (Figure 1d), indicating its low density. The microstructure of the CNF/PVA/GO carbon aerogel was observed by SEM (Figure 2a, 2b, and 2d). As shown in Figure 2a, the CNF/PVA/GO carbon aerogel showed porous and interconnected 3D structures with pore size ranging from 50–75 μm. The carbon skeleton originated

Engineering of oriented carbon nanotubes in composite materials

• Razieh Beigmoradi,
• Abdolreza Samimi and
• Davod Mohebbi-Kalhori

Beilstein J. Nanotechnol. 2018, 9, 415–435, doi:10.3762/bjnano.9.41

• more on the quality of the CNTs than the ability to control the interactions of the CNT and LC [84]. Filtration method Filtering a well-dispersed and dilute solution of CNTs through a porous membrane may lead to the arrangement of the CNTs [99]. A very narrow pore size distribution (a thousand

Photocatalytic and adsorption properties of TiO₂-pillared montmorillonite obtained by hydrothermally activated intercalation of titanium polyhydroxo complexes

• Mikhail F. Butman,
• Nikolay L. Ovchinnikov,
• Nikita S. Karasev,
• Nataliya E. Kochkina,
• Alexander V. Agafonov and
• Alexandr V. Vinogradov

Beilstein J. Nanotechnol. 2018, 9, 364–378, doi:10.3762/bjnano.9.36

• also observed in [42] and related to the growth of TiO2 anatase crystals. The pore size distribution curves are shown in Figure 6b. The distribution pattern for the TiO2-PMMx samples is narrow and unimodal. The samples prepared using hydrothermal treatment feature a shift of the distribution curve to

• analysis (TGA)/differential scanning calorimetry (DSC) curves of the raw MM, Ti-MM, and Ti-MMH. SEM images and EDS spectra of the surface of (a) TiO2-PMM500, and (b) TiO2-PMMH500. Nitrogen adsorption/desorption isotherms (а) and pore size distribution (b) of the raw MM, TiO2-PMMx, and TiO2-PMMHx. Kinetic

Bombyx mori silk/titania/gold hybrid materials for photocatalytic water splitting: combining renewable raw materials with clean fuels

• Stefanie Krüger,
• Michael Schwarze,
• Otto Baumann,
• Christina Günter,
• Michael Bruns,
• Christian Kübel,
• Dorothée Vinga Szabó,
• Rafael Meinusch,
• Verónica de Zea Bermudez and
• Andreas Taubert

Beilstein J. Nanotechnol. 2018, 9, 187–204, doi:10.3762/bjnano.9.21

• of 5 and 7–18 nm, respectively. Addition of poly(ethylene oxide) to the reaction mixture enables pore size tuning, thus providing access to different materials with different photocatalytic activities. Water splitting experiments using a sunlight simulator and a Xe lamp show that the new hybrid

• very broad pore diameter distribution. The cumulative pore volume indicates a very undefined porosity with pore sizes mainly in the range of 200 nm and 50 µm. In contrast, in the case of monolithic TPS samples (i.e., samples that were not ground prior to analysis), the pore size distribution is

• narrower pore size distribution than the TPS samples. In the powdered sample, the pores are mainly on the order of 500 nm to 30 µm whereas the monolithic sample shows pores below 10 nm and from 500 nm to 5 µm with a rather pronounced main pore diameter at 1 µm. As the purpose of the materials presented

One-step chemical vapor deposition synthesis and supercapacitor performance of nitrogen-doped porous carbon–carbon nanotube hybrids

• Egor V. Lobiak,
• Lyubov G. Bulusheva,
• Ekaterina O. Fedorovskaya,
• Yury V. Shubin,
• Pavel E. Plyusnin,
• Pierre Lonchambon,
• Boris V. Senkovskiy,
• Zinfer R. Ismagilov,
• Emmanuel Flahaut and
• Alexander V. Okotrub

Beilstein J. Nanotechnol. 2017, 8, 2669–2679, doi:10.3762/bjnano.8.267

• -existence of CNTs and nontubular carbon (Figure S1 in Supporting Information File 1). TEM images revealed that the nontubular carbon is highly porous with a pore size between 8–20 nm (Figure 2). High-resolution TEM images demonstrated the layered structure of these carbons (Figure S2 in Supporting

• Information File 1). Since the average pore size determined from the N2 sorption measurements was ≈12 nm for all samples, we conclude that this carbon material was templated by MgO nanoparticles. The nanotubes permeate the porous carbon (Figure 2a,c,f) and connect the flakes (Figure 2b). The supported metals

Enhanced photoelectrochemical water splitting performance using morphology-controlled BiVO₄ with W doping

• Xin Zhao and
• Zhong Chen

Beilstein J. Nanotechnol. 2017, 8, 2640–2647, doi:10.3762/bjnano.8.264

• , the pore size decreases. The film prepared from the water-based solution with the smallest amount of EG (0.5-EG) exhibits cracks in the film (Figure S2, Supporting Information File 1) and has poor adhesion to the substrate. The sol–gel method allows reagents to be mixed at the atomic/molecular level

Fabrication of carbon nanospheres by the pyrolysis of polyacrylonitrile–poly(methyl methacrylate) core–shell composite nanoparticles

• Dafu Wei,
• Youwei Zhang and
• Jinping Fu

Beilstein J. Nanotechnol. 2017, 8, 1897–1908, doi:10.3762/bjnano.8.190

• point of nitrogen using a surface area and porosity analyzer (ASAP2020, Micromeritics). The specific surface area of the samples was calculated according to BET theory. The pore size of carbon nanospheres was calculated from the desorption branch of nitrogen isotherms using the Barret–Joyner–Halenda

• adsorption isotherm with H3 hysteresis, indicating the presence of mesopores. This was consistent with the result of the pore size distribution displayed in Figure 8b. The pore size of CP6 ranged from 1.75 nm to 125 nm, with majority of them lying in the range of mesopores. The calculated BET specific

• SiO2 (178.49 mg/g) [54], manganese-impregnated zinc sulphide nanoparticles deposited on activated carbon (191.57 mg/g) [55] and γ-Fe2O3 loaded active carbon (195.55 mg/g) [56]. We believe the efficient removal of MB is mainly attributed to the small pore size and the high specific surface area of CP6

Carbon nano-onions as fluorescent on/off modulated nanoprobes for diagnostics

• Stefania Lettieri,
• Marta d’Amora,
• Adalberto Camisasca,
• Alberto Diaspro and
• Silvia Giordani

Beilstein J. Nanotechnol. 2017, 8, 1878–1888, doi:10.3762/bjnano.8.188

• h. The oxi-CNOs were separated from the reaction mixture by centrifugation (15 min at 1800 rpm) and filtered off on a nylon filter membrane (pore size 0.2 µm) and washed with dH2O, DMF, methanol and acetone. After drying overnight at RT, 51.2 mg of oxi-CNOs were obtained as a black powder. fluo-CNOs

• (0.0044 mmol) of BODIPY 3, and the mixture was stirred at room temperature for 20 h under di-nitrogen atmosphere. The fluo-CNOs were filtered off thought a nylon membrane (pore size 0.2 µm) and washed with fresh DMF, THF and MeOH to remove the unreacted dye and the remaining reagents. 9.7 mg of fluo-CNOs

Evaluation of preparation methods for suspended nano-objects on substrates for dimensional measurements by atomic force microscopy

• Petra Fiala,
• Daniel Göhler,
• Benno Wessely,
• Michael Stintz,
• Giovanni Mattia Lazzerini and
• Andrew Yacoot

Beilstein J. Nanotechnol. 2017, 8, 1774–1785, doi:10.3762/bjnano.8.179

• of polycarbonate (pore size 30 nm and 50 nm, Sterlitech Corp, Kent, USA and 100 nm, Merck Millipore, Darmstadt, Germany) as well as on silicon wafers (crystal orientation <100>) and on silicon wafers (crystal orientation <100>) coated with silicon dioxide. SEM measurements were performed for all

• preparation methods in which all of precipitated particles are deposited on the substrate, so the estimation is relevant for membrane filtration (if particle size > pore size) and droplet drying. Membrane filtration: The membranes were fixed and flowed off in a filter element (stainless steel 316, diameter 13

Oxidative stabilization of polyacrylonitrile nanofibers and carbon nanofibers containing graphene oxide (GO): a spectroscopic and electrochemical study

• İlknur Gergin,
• Ezgi Ismar and
• A. Sezai Sarac

Beilstein J. Nanotechnol. 2017, 8, 1616–1628, doi:10.3762/bjnano.8.161

• these pores are well distributed on the fibers. The morphological property of the porous carbon electrodes such as the surface and pore size distributions are the factor that influences the double-layer capacitance. Therefore, the pore size distribution of porous carbons also affect the performance of

• carbon-based electrochemical capacitors [58]. According to SEM images (Figure 11b) pore size on the nanofibers were measured as 38.5 ± 11 nm. All morphologic characterizations prove the porous structure of GO containing nanofibers. In supercapacitors that use nanoporous electrodes to store large amounts

• of charge, ions penetrate into the pores of the electrode. Raymundo-Piñero et al. considered that an adequate pore size is more important than a high surface area and reported optimum pore sizes as 0.7 nm and 0.8 nm in aqueous and organic media, respectively [59]. Graphene oxide shows a high specific

Miniemulsion copolymerization of (meth)acrylates in the presence of functionalized multiwalled carbon nanotubes for reinforced coating applications

• Bertha T. Pérez-Martínez,
• Lorena Farías-Cepeda,
• Víctor M. Ovando-Medina,
• José M. Asua,
• Lucero Rosales-Marines and
• Radmila Tomovska

Beilstein J. Nanotechnol. 2017, 8, 1328–1337, doi:10.3762/bjnano.8.134

• the MWCNTs was reported. The resulting nanocomposites were foamed with supercritical CO2. The foams showed a decreased pore size, an increased cell density and higher volume expansion when the MWCNT concentration increased. Capek and Kocsisova [35] studied the effect of the type and concentration of

Fabrication of hierarchically porous TiO₂ nanofibers by microemulsion electrospinning and their application as anode material for lithium-ion batteries

• Jin Zhang,
• Yibing Cai,
• Xuebin Hou,
• Xiaofei Song,
• Pengfei Lv,
• Huimin Zhou and
• Qufu Wei

Beilstein J. Nanotechnol. 2017, 8, 1297–1306, doi:10.3762/bjnano.8.131

• theory. In addition, Figure 5b displays the pore-size distribution of sample A2, sample B2 and sample C2. According to the analysis of pore-size distribution with the Barrett–Joyner–Halenda (BJH) method, the average pore size increased gradually, and the average pore diameter was 17.8, 18.5 and 20.1 nm

• TEM images of sample A2 (h). (a) Nitrogen adsorption–desorption curves of sample A2, sample B2, sample C2 and solid TiO2 nanofibers; (b) pore-size distribution of sample A2, sample B2, sample C2. Galvanostatic charge–discharge curves of sample A2 (a), sample B2 (b) and sample C2 (c) for the first ten

Nanotopographical control of surfaces using chemical vapor deposition processes

• Meike Koenig and
• Joerg Lahann

Beilstein J. Nanotechnol. 2017, 8, 1250–1256, doi:10.3762/bjnano.8.126

• solid monomer and polymerization. Following the deposition process, the solid monomer is removed via sublimation, leading to membrane structures with dual-scale porosity. The growth rate and the pore size of the resulting membrane can be controlled by the reactor parameters, such as deposition time

• and patterned coatings from a great variety of polymer materials can be created that can be tailored to the respective applications. Polymer structures via masked deposition: polypyrrole nanotubes by deposition using aluminum oxide membranes with a pore size of 100 nm as the template. The wall

A top-down approach for fabricating three-dimensional closed hollow nanostructures with permeable thin metal walls

• Carlos Angulo Barrios and
• Víctor Canalejas-Tejero

Beilstein J. Nanotechnol. 2017, 8, 1231–1237, doi:10.3762/bjnano.8.124

• permeability (e.g., role of porosity, pore size control, diffusion constants, effect of Al thickness and degree of oxidation), which is beyond the scope of this preliminary proof-of-concept work, should provide deeper insight into the mechanisms of the demonstrated emptying process. Figure 3a shows the

Hierarchically structured nanoporous carbon tubes for high pressure carbon dioxide adsorption

• Julia Patzsch,
• Deepu J. Babu and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2017, 8, 1135–1144, doi:10.3762/bjnano.8.115

• linearized isotherm equation between P/P0 0.035 and 0.2 and the pore size was calculated by density functional theory (DFT) for slit pores. The scanning electron microscopy (SEM) micrographs were obtained using a Philips XL 30 FEG (20 kV) instrument equipped with an EDX (energy dispersive X-ray) detector

• supermicropores have undergone an irreversible expansion after high pressure CO2 adsorption. This is also confirmed by the pore size distribution analysis (Figure 10b) which indicates a decrease in the fraction of micropores and an increase in the content of mesopores. The higher contribution of the mesopores to

• the total surface area (Table 1) after high pressure CO2 adsorption (37.4% compared to 5.5% for the as-prepared carbon tubes (4)) from the t-plot analysis is consistent with results obtained from the pore size distribution analysis. The internal stress induced by the adsorbed CO2 under high pressure

Structural properties and thermal stability of cobalt- and chromium-doped α-MnO₂ nanorods

• Romana Cerc Korošec,
• Polona Umek,
• Alexandre Gloter,
• Jana Padežnik Gomilšek and
• Peter Bukovec

Beilstein J. Nanotechnol. 2017, 8, 1032–1042, doi:10.3762/bjnano.8.104

• ]. The size and shape of different tunnel sizes (1 × 1, 1 × 2, 2 × 2, 3 × 3, 3 × 2, 2 × 4) direct the pore opening and control the separation [1][4]. In α-MnO2, octahedrons form the 2 × 2 channel structure with a pore size of 4.6 Å [5]. In the structure named cryptomelane hydrated K+ cations are

Bio-inspired micro-to-nanoporous polymers with tunable stiffness

• Julia Syurik,
• Ruth Schwaiger,
• Prerna Sudera,
• Stephan Weyand,
• Siegbert Johnsen,
• Gabriele Wiegand and
• Hendrik Hölscher

Beilstein J. Nanotechnol. 2017, 8, 906–914, doi:10.3762/bjnano.8.92

• analysis of the pore structure. Therefore, our approach represents a non-chemical way to tune the elastic properties and their local variation for a broad range of polymers by adjusting the pore size gradient. Keywords: biomimetics; polymeric materials; supercritical carbon dioxide (SC-CO2); tunable

• improvement of re-usability and durability of the products. Porous structures with a pore-size gradient have been manufactured in the past from different materials such as ceramics [6][7][8], metals [9], composites [10] and polymers [11]. These structures exhibited improved thermal [12] and mechanical

• is subjected to inhomogeneous pressure and/or temperature conditions during steps (ii) and (iii), the pore size within the polymer can vary [20]. To the best of our knowlegde, the correlation between the density of the porous material and its storage modulus, especially the size-dependent mechanical

First examples of organosilica-based ionogels: synthesis and electrochemical behavior

• Andreas Taubert,
• Ruben Löbbicke,
• Barbara Kirchner and
• Fabrice Leroux

Beilstein J. Nanotechnol. 2017, 8, 736–751, doi:10.3762/bjnano.8.77

• onset of significant nitrogen uptake and the parallel adsorption and desorption branches also indicate the presence of rather small pores and a relatively narrow pore size distribution [37]. Analysis of the SAXS data using the Porod-approach [37][38][39][40] confirms this, although pore sizes determined

• , however, not the case here. We never observe cracking or other pore collapse. This is likely due to the flexibility of the organic bridges that enable the dry solid to respond to local mechanical stress without breaking or pore collapse. Table 1 also shows that the pore size and open pore volume strongly

• , pore size, and open pore volume. The same observation applies to materials obtained with MTMS instead of TMOS in acetone. High surface areas up to 740 cm3/g, high open pore volumes of around 60%, and pore sizes between 3 and 5 nm are also obtained in this system. In contrast, the methanol-based

Phospholipid arrays on porous polymer coatings generated by micro-contact spotting

• Sylwia Sekula-Neuner,
• Monica de Freitas,
• Lea-Marie Tröster,
• Tobias Jochum,
• Pavel A. Levkin,
• Michael Hirtz and
• Harald Fuchs

Beilstein J. Nanotechnol. 2017, 8, 715–722, doi:10.3762/bjnano.8.75

• ], emphasizes the need for sustained progress in this field. The work presented here demonstrates the potential of nanoporous poly(2-hydroxyethyl methacrylate-co-ethylene dimethacrylate) (HEMA-EDMA) as a novel advantageous substrate for lipid arrays. Porous HEMA support, with pore size distribution in the range

Synthesis of graphene–transition metal oxide hybrid nanoparticles and their application in various fields

• Arpita Jana,
• Elke Scheer and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2017, 8, 688–714, doi:10.3762/bjnano.8.74

Ion beam profiling from the interaction with a freestanding 2D layer

• Ivan Shorubalko,
• Kyoungjun Choi,
• Michael Stiefel and
• Hyung Gyu Park

Beilstein J. Nanotechnol. 2017, 8, 682–687, doi:10.3762/bjnano.8.73

• dwell times ranging from 0.5 to 10 ms. A clear dependence of the pore size on the exposure dose is observed. It is also seen that pores can have slightly irregular shapes. In order to precisely extract pore diameters from such experiments, we perforated sets of pores with identical exposure parameters

• important issue is high-resolution imaging of the pores. When pore size becomes smaller than a few nanometers, like in the case of 1–3 pA He+ beams, it is difficult to measure these pore dimensions precisely with standard STEM or HIM. Time consuming high-resolution TEM imaging would be required. The third

Dispersion of single-wall carbon nanotubes with supramolecular Congo red – properties of the complexes and mechanism of the interaction

• Anna Jagusiak,
• Barbara Piekarska,
• Tomasz Pańczyk,
• Małgorzata Jemioła-Rzemińska,
• Elżbieta Bielańska,
• Barbara Stopa,
• Grzegorz Zemanek,
• Janina Rybarska,
• Irena Roterman and
• Leszek Konieczny

Beilstein J. Nanotechnol. 2017, 8, 636–648, doi:10.3762/bjnano.8.68

• . Polytetrafluoroethylene (PTFE) membranes (0.2 µm pore size) were purchased from MERCK Millipore. All other reagents used were of analytical grade. Dispersion of SWNTs by non-covalent attachment of supramolecular Congo red 1 mL of aqueous CR solution (2 or 5 mg/mL) was heated for 3 min at 100 °C, slowly cooled to room

Liquid permeation and chemical stability of anodic alumina membranes

• Dmitrii I. Petukhov,
• Dmitrii A. Buldakov,
• Alexey A. Tishkin,
• Alexey V. Lukashin and
• Andrei A. Eliseev

Beilstein J. Nanotechnol. 2017, 8, 561–570, doi:10.3762/bjnano.8.60

• and exceptional transport characteristics. A very narrow pore size distribution, low pore tortuosity and controllable membrane porosity make AAO one of the top performers given its permeability/pore diameter ratio [1]. The synthetic procedure of AAO membranes enables significant tunability of the

• media [1][13][14][15]. In contrast, the narrow pore size distribution of anodic alumina membranes should result in a sharp cut-off curve and excellent filtration characteristics [1]. The possible reason for low publishing and application activity in the field is the degradation of AAO membrane materials