Ammonia gas sensors based on In₂O₃/PANI hetero-nanofibers operating at room temperature

• Qingxin Nie,
• Zengyuan Pang,
• Hangyi Lu,
• Yibing Cai and
• Qufu Wei

Beilstein J. Nanotechnol. 2016, 7, 1312–1321, doi:10.3762/bjnano.7.122

• electrospinning, and then hollow structure indium oxide (In2O3) nanofibers were obtained through calcination with PVP as template material. In situ polymerization was used to prepare indium oxide/polyaniline (In2O3/PANI) composite nanofibers with different mass ratios of In2O3 to aniline. The structure and

• [21][23][24][25][26][27]. In this paper, In2O3/PANI composite nanofibers were prepared by the combination of electrospinning technique, calcination method and in situ polymerization. This study presents the improved response capabilities of gas sensors based on In2O3/PANI composite nanofibers, which

• were synthesized with different ratios between In2O3 and aniline during the in situ polymerization. All sensors were tested at room temperature in a concentration range of NH3 from 100 to 1000 ppm. Experimental Materials Polyvinylpyrrolidone-K90 (PVP-K90, Mw = 1.3 × 106 g/mol) was purchased from Bo Di

Reasons and remedies for the agglomeration of multilayered graphene and carbon nanotubes in polymers

• Rasheed Atif and
• Fawad Inam

Beilstein J. Nanotechnol. 2016, 7, 1174–1196, doi:10.3762/bjnano.7.109

• shown in Figure 10 [53]. Nayak et al. [118] carried out the solvent-free side-wall functionalization of SWNTs with 4-vinylaniline through atom transfer radical polymerization. Different functional groups yield varying interfacial interaction strengths with the polymer matrix [118]. MLG and CNTs can be

• grafted covalently into polymers using two main strategies: (i) “grafting from” and (ii) “grafting to” [2]. In the “grafting from” approach, initiators are initially immobilized onto the surface of the filler. The fillers are bound with desired polymer molecules by in situ polymerization. The main

• impact strength and hardness were also significantly improved by graphene in epoxy nanocomposites. For example, Ren et al. applied a combination of bath sonication, mechanical mixing, and shear mixing to disperse GO in cyanate ester–epoxy and produced nanocomposites using in situ polymerization [159

An ellipsometric approach towards the description of inhomogeneous polymer-based Langmuir layers

• Falko O. Rottke,
• Burkhard Schulz,
• Klaus Richau,
• Karl Kratz and
• Andreas Lendlein

Beilstein J. Nanotechnol. 2016, 7, 1156–1165, doi:10.3762/bjnano.7.107

• . In the following a short summary of the methods and the characterization of the polymers are given. PPDL-D4 was synthesized by tin(II)-mediated ring-opening polymerization of ω-pentadecalactone and di(trimethylolpropane) as the core segment. For PPDL-D4 a molecular weight Mn of 5000 g·mol−1 was

Reconstitution of the membrane protein OmpF into biomimetic block copolymer–phospholipid hybrid membranes

• Matthias Bieligmeyer,
• Franjo Artukovic,
• Stephan Nussberger,
• Thomas Hirth,
• Thomas Schiestel and
• Michaela Müller

Beilstein J. Nanotechnol. 2016, 7, 881–892, doi:10.3762/bjnano.7.80

• ). According to anionic polymerization theory, the amount of 1,4-isoprene units in PIPEOs was larger than 88% due to the polymerization in toluene and the polydispersity indices (PDI) being relatively low (Table 1). Only PIPEO877 showed an increased polydispersity index, which was likely caused by the high

• amount of sec-butyllithium used as initiator to obtain the low molecular weight of the polymer. The polydispersity indices of the PIPEO block copolymers were slightly larger than those of the PI precursors, probably because of side reactions during the polymerization of ethylene oxide utilizing the

• and stirred for 1 h over di-n-butylmagnesium under the same conditions. To transfer the solvent and the monomers from one flask to another, cryo-distillation under static vacuum conditions was used. The typical procedure for polymerization of the block copolymers is briefly mentioned here. To a volume

Assembling semiconducting molecules by covalent attachment to a lamellar crystalline polymer substrate

• Rainhard Machatschek,
• Patrick Ortmann,
• Renate Reiter,
• Stefan Mecking and
• Günter Reiter

Beilstein J. Nanotechnol. 2016, 7, 784–798, doi:10.3762/bjnano.7.70

• synthesis Details of the synthesis of the CPE45 polymer and the nanocrystals have been published elsewhere [8]. In brief, acyclic diene metathesis (ADMET) polymerization of an carboxylic acid functionalized α,ω-diene monomer was used, which was prepared in a multistep synthetic approach. Nanocrystals were

Fabrication and characterization of novel multilayered structures by stereocomplexion of poly(D-lactic acid)/poly(L-lactic acid) and self-assembly of polyelectrolytes

• Elena Dellacasa,
• Li Zhao,
• Gesheng Yang,
• Laura Pastorino and
• Gleb B. Sukhorukov

Beilstein J. Nanotechnol. 2016, 7, 81–90, doi:10.3762/bjnano.7.10

• distribution) were obtained via ring-opening polymerization. The molecular weight of PDLA and PLLA are 37511 and 59223 g/mol, respectively. This was suitable for our usage due to the use of polymers with similar molecular weights in LBL assembly [46]. Thus, these polymers were used for LBL assembly directly

• 18.2 MΩ·cm. Methods Synthesis and characterization of PLLA and PDLA Typically, 10 g of lactide and 0.5% tannous octoate (as a catalyst) were added to a conical flask. Then the conical flask was place into a vacuum oven at 180° after being sealed and the ring-opening polymerization lasted for 12 h

Plasma fluorination of vertically aligned carbon nanotubes: functionalization and thermal stability

• Claudia Struzzi,
• Mattia Scardamaglia,
• Axel Hemberg,
• Luca Petaccia,
• Jean-François Colomer,
• Rony Snyders and
• Carla Bittencourt

Beilstein J. Nanotechnol. 2015, 6, 2263–2271, doi:10.3762/bjnano.6.232

• polymerization, the introduction of unwanted atoms on the functionalized system, or the high toxicity level of the gas used. Carbon tetrafluoride (CF4), sulfur hexafluoride (SF6), pure fluorine (F2) or diluted fluorine in an inert atmosphere (Xe/F2, Ar/F2) are the precursor gases most commonly used. In the case

Selective porous gates made from colloidal silica nanoparticles

• Roberto Nisticò,
• Paola Avetta,
• Paola Calza,
• Debora Fabbri,
• Giuliana Magnacca and
• Dominique Scalarone

Beilstein J. Nanotechnol. 2015, 6, 2105–2112, doi:10.3762/bjnano.6.215

• hexagonally ordered pores were also employed as substrate for MCM-48 silica films, giving promising results [4][23][24]. The sol–gel polymerization process is a key procedure for the bottom-up synthesis of nano- and mesoporous silica films and in the literature there are several reviews focusing on this field

Nanostructured superhydrophobic films synthesized by electrodeposition of fluorinated polyindoles

• Gabriela Ramos Chagas,
• Thierry Darmanin and
• Frédéric Guittard

Beilstein J. Nanotechnol. 2015, 6, 2078–2087, doi:10.3762/bjnano.6.212

• extremely various shapes can be produced in solution by self-assembly [19][20][21] or directly formed on substrates by different strategies such as preferential growth [22], grafting [23], vapor phase polymerization [24], plasma polymerization [25] and electropolymerization [26][27][28][29][30]. The last

• method allows for a very quick and easy deposition of conducting polymer films while the formation of surface structures can be controlled by electrochemical parameters [26] and the used monomer [27]. In order to control the formation of surface nanostructures, the core responsible for the polymerization

• for Indole-6-F6 is shown in Figure 1, where it is possible to see the maximum peak of oxidation of the monomer. Then, the polymerization was followed from −0.7 V to a potential slightly lower than Eox (working potential Ew) by the same electrochemical method. Examples of cyclic voltammograms for the

Electrochemical behavior of polypyrrol/AuNP composites deposited by different electrochemical methods: sensing properties towards catechol

• Celia García-Hernández,
• Cristina García-Cabezón,
• Cristina Medina-Plaza,
• Fernando Martín-Pedrosa,
• Yolanda Blanco,
• José Antonio de Saja and
• María Luz Rodríguez-Méndez

Beilstein J. Nanotechnol. 2015, 6, 2052–2061, doi:10.3762/bjnano.6.209

• this reason, they have been widely used as chemical sensors for the detection of a variety of substances. The structure and sensing properties of the Ppy films are considerably influenced by the electrochemical method used for the polymerization (potentiostatic, galvanostatic or potentiodynamic), by

• [13], ammonia gas at room temperature [14], caffeine [15] or hydroxylamine [16] among others. Ppy/AuNP composites can be prepared by chemical and electrochemical polymerization. Electrochemical methods provide a better control of the structure and properties of the composite by controlling the

• sensing properties of the Ppy/AuNPs films directly depend on the polymerization conditions. However, the influence of the polymerization conditions in the properties of Ppy/AuNPs electrodes has not been yet studied. One of the fields where electrochemical sensors are having an important success is in the

Focused particle beam-induced processing

• Michael Huth and
• Armin Gölzhäuser

Beilstein J. Nanotechnol. 2015, 6, 1883–1885, doi:10.3762/bjnano.6.191

• polymerization that is a basis for the creation of ultrathin nanomembranes. Finally, André Beyer and coworkers show impressive HIM images of ultrathin carbon nanomembranes [17], which is a clear indication of the potential of the bourgeoning fields of helium ion microscopy and lithography towards nanofabrication

Radiation losses in the microwave K_u band in magneto-electric nanocomposites

• Talwinder Kaur,
• Sachin Kumar,
• Jyoti Sharma and
• A. K. Srivastava

Beilstein J. Nanotechnol. 2015, 6, 1700–1707, doi:10.3762/bjnano.6.173

• explained. Further studies revealed that the prepared material is a nanocomposite. FTIR spectra show the presence of expected chemical structures such as C–H bonds in a ring system at 1512 cm−1. Keywords: emulsion polymerization; magneto-electric composite; radiation loss; vector network analyser

• paper, we have used the versatile citrate precursor method to synthesize La–Co-substituted barium hexaferrite. Lanthanum and cobalt are used as substituents to enhance the magnetic properties of barium hexaferrite and then emulsion polymerization is employed for the synthesis of nanocomposites. The

• material (BaM) and aniline are mixed in the ratio of 1:1. The solution is stirred 3–4 h at very low temperature for micelle formation. To initiate the polymerization, ammonium persulfate is used as an initiator that initiates the reaction at 2 °C. The obtained product is filtered with a suction pump and

Atomic force microscopy as analytical tool to study physico-mechanical properties of intestinal cells

• Christa Schimpel,
• Oliver Werzer,
• Eleonore Fröhlich,
• Gerd Leitinger,
• Markus Absenger-Novak,
• Birgit Teubl,
• Andreas Zimmer and
• Eva Roblegg

Beilstein J. Nanotechnol. 2015, 6, 1457–1466, doi:10.3762/bjnano.6.151

• thus responsible for polymerization of monomeric actin to microfilaments and/or the linkage of single microfilaments into hexagonally packed bundles [6][39]. According to the literature, villin is localized at the apex of cells that display a well-developed brush border [40]. In M cells, however

DNA–melamine hybrid molecules: from self-assembly to nanostructures

• Rina Kumari,
• Shib Shankar Banerjee,
• Anil K. Bhowmick and
• Prolay Das

Beilstein J. Nanotechnol. 2015, 6, 1432–1438, doi:10.3762/bjnano.6.148

• could be used for various potential applications including templated polymerization or metallization. Several strategies have been developed to generate self-assembled DNA nanostructures based on DNA–organic hybrid molecular building blocks. The selection of organic molecule and the DNA sequence are the

Peptide-equipped tobacco mosaic virus templates for selective and controllable biomineral deposition

• Klara Altintoprak,
• Axel Seidenstücker,
• Alexander Welle,
• Sabine Eiben,
• Petia Atanasova,
• Nina Stitz,
• Alfred Plettl,
• Joachim Bill,
• Hartmut Gliemann,
• Holger Jeske,
• Dirk Rothenstein,
• Fania Geiger and
• Christina Wege

Beilstein J. Nanotechnol. 2015, 6, 1399–1412, doi:10.3762/bjnano.6.145

• mineralization-directing peptides designed to yield silica coatings in a reliable and predictable manner via precipitation from tetraethoxysilane (TEOS) precursors. Three peptide groups were compared regarding their influence on silica polymerization: (i) two peptide variants with alternating basic and acidic

• residues, i.e. lysine–aspartic acid (KD)x motifs expected to act as charge-relay systems promoting TEOS hydrolysis and silica polymerization; (ii) a tetrahistidine-exposing polypeptide (CA4H4) known to induce silicification due to the positive charge of its clustered imidazole side chains; and (iii) two

Electrical characterization of single molecule and Langmuir–Blodgett monomolecular films of a pyridine-terminated oligo(phenylene-ethynylene) derivative

• Henrry M. Osorio,
• Santiago Martín,
• María Carmen López,
• Santiago Marqués-González,
• Simon J. Higgins,
• Richard J. Nichols,
• Paul J. Low and
• Pilar Cea

Beilstein J. Nanotechnol. 2015, 6, 1145–1157, doi:10.3762/bjnano.6.116

• groups [67][68][69] and fullerenes [60][70][71]. However, many of these groups have significant limitations including chemical degradation at working temperatures [72][73], associated polymerization phenomena [74], small binding energies [74], unexpectedly high contact resistance [75][76][77][78][79][80

In situ observation of biotite (001) surface dissolution at pH 1 and 9.5 by advanced optical microscopy

• Chiara Cappelli,
• Daniel Lamarca-Irisarri,
• Jordi Camas,
• F. Javier Huertas and
• Alexander E. S. Van Driessche

Beilstein J. Nanotechnol. 2015, 6, 665–673, doi:10.3762/bjnano.6.67

• the biotite structure; (2) hydrolysis of the Si–O–Si and Si–O–Al groups of the tetrahedral sheet, responsible for the layer expansion and (3) re-polymerization of Si–OH groups to form Si–O–Si that might cause layer contraction by expulsion of water. In a new concept of the mineral/solution interface

Simple approach for the fabrication of PEDOT-coated Si nanowires

• Mingxuan Zhu,
• Marielle Eyraud,
• Judikael Le Rouzo,
• Nadia Ait Ahmed,
• Florence Boulc’h,
• Claude Alfonso,
• Philippe Knauth and
• François Flory

Beilstein J. Nanotechnol. 2015, 6, 640–650, doi:10.3762/bjnano.6.65

• electrochemical methods. Since the polymerization reaction is a very fast process with regards to monomer diffusion along the SiNW, the conformal deposition by classical, fixed potential deposition was not favored. Instead, the core–shell heterojunction structure was finally achieved by a pulsed deposition method

• . An extremely large shunt resistance was exhibited and determined to be related to the diffusion conditions occurring during polymerization. Keywords: conductive polymer; core–shell structure; electrodeposition; hybrid material; SiNW; Introduction Silicon nanowires (SiNWs) are a current, active

• surface uncovered [16]. In order to improve the junction quality, a conformal PEDOT shell should be introduced to eliminate charge transport paths parallel to the diode. Compared with the spin coating technique, the electrochemical polymerization of PEDOT provides the possibility of excellent polymer

Self-assembled anchor layers/polysaccharide coatings on titanium surfaces: a study of functionalization and stability

• Ognen Pop-Georgievski,
• Dana Kubies,
• Josef Zemek,
• Neda Neykova,
• Roman Demianchuk,
• Eliška Mázl Chánová,
• Miroslav Šlouf,
• Milan Houska and
• František Rypáček

Beilstein J. Nanotechnol. 2015, 6, 617–631, doi:10.3762/bjnano.6.63

• -aminopropyltriethoxysilane (APTES) can result in several surface structures such as covalent attachment, self-assembly, multilayer formation by surface-initiated (SI) polymerization and particle adsorption [22]. The obstacles and limitations inherent to thiol–SAMs and silanes can be circumvented by the use of moieties

• dopamine and its intermediates (dopamine-quinone, 5,6-dihydroxyindole, etc.), of SI polymerization and of adsorption of the resulting polymer molecules resulted in a 15.2 ± 0.5 nm thick confluent PDA layer. Despite the precautions taken during the APTES deposition for the formation of the SAM [21] (freshly

• surface, but also proves the presence of the siloxane polymer network. The network is formed by SI polymerization from non-hydrolyzed ethoxy groups (which can give rise to silanol groups) and free silanols that did not undergo a dehydration condensation reaction with surface hydroxy groups. Both possible

Silica micro/nanospheres for theranostics: from bimodal MRI and fluorescent imaging probes to cancer therapy

• Shanka Walia and
• Amitabha Acharya

Beilstein J. Nanotechnol. 2015, 6, 546–558, doi:10.3762/bjnano.6.57

• was then activated by silane-carrying methacrylate and 3-(methacryloyloxy)propyltrimethoxysilane (MPTS). Finally, a lightly crosslinked poly(N-isopropylacrylamide) (PNIPAAm) shell was immobilized by a graft polymerization process. The characterization of these NPs was carried out through DLS, TEM, VSM

• -functionalized CdTe QDs were conjugated with the magnetic NPs inside the silica shell. Finally, the silica-coated NPs were wrapped with thermosensitive poly(N-isopropylacrylamide) by a template polymerization process. The average diameter of silica-coated magnetic NPs was found to be 100 ± 10 nm as studied by

• nanocomposite material composed of a magnetic silica core and a fluorescent shell by combining two different techniques, namely heterocoagulation and soap-free emulsion polymerization. The N-trimethoxysilylpropyl-N,N,N-trimethylammonium chloride (TSA)-modified Fe3O4 NPs were prepared by the Massart method and

Hematopoietic and mesenchymal stem cells: polymeric nanoparticle uptake and lineage differentiation

• Ivonne Brüstle,
• Thomas Simmet,
• Gerd Ulrich Nienhaus,
• Katharina Landfester and
• Volker Mailänder

Beilstein J. Nanotechnol. 2015, 6, 383–395, doi:10.3762/bjnano.6.38

• particles were fluorescently labeled with the fluorescent dye N-(2,6-diisopropylphenyl)perylene-3,4-dicarboximide (PMI). The magnetite was encapsulated for magnetic resonance purposes. The polymeric nanoparticles used in this work were obtained by miniemulsion polymerization (non-functionalized and

Comparative evaluation of the impact on endothelial cells induced by different nanoparticle structures and functionalization

• Lisa Landgraf,
• Ines Müller,
• Peter Ernst,
• Miriam Schäfer,
• Christina Rosman,
• Isabel Schick,
• Oskar Köhler,
• Hartmut Oehring,
• Vladimir V. Breus,
• Thomas Basché,
• Carsten Sönnichsen,
• Wolfgang Tremel and
• Ingrid Hilger

Beilstein J. Nanotechnol. 2015, 6, 300–312, doi:10.3762/bjnano.6.28

• endocytotic processes were assessed. SVEC4-10 cells were pre-incubated with 5 µg/mL cytochalasin D (inhibitor of actin polymerization, indicator of caveolae and macropinocytosis) [74], 100 nM wortmannin (inhibitor of PI3 kinase, indicator of macropinocytosis) [75], 5 µg/mL nocodazol (promotes microtubule

Tailoring the ligand shell for the control of cellular uptake and optical properties of nanocrystals

• Johannes Ostermann,
• Christian Schmidtke,
• Christopher Wolter,
• Jan-Philip Merkl,
• Hauke Kloust and
• Horst Weller

Beilstein J. Nanotechnol. 2015, 6, 232–242, doi:10.3762/bjnano.6.22

• against dilution can be achieved. By carefully choosing the monomers, reaction conditions and block length ratios it is possible to reproducibly synthesize very defined ligands, using anionic polymerization techniques [10]. One advantage of this reaction type is the absence of chain transfer and

• Ligand synthesis The synthesis of amphiphilic polyisoprene-block-poly(ethylene glycol) (PI-b-PEG) was realized via anionic polymerization, using standard high vacuum reaction techniques [10][20]. Isoprene was polymerized in dry THF by the quick addition of sec-butyllithium at −40 °C. After completion of

• solvate separated ion pair, which is capable of starting the polymerization of ethylene oxide at room temperature (Scheme 1). Using this reaction path a variety of PI homopolymers and PI-b-PEG diblock copolymers differing in size and block length ratio were synthesized (Table 1). The aggregation of the PI

Synthesis of boron nitride nanotubes and their applications

• Saban Kalay,
• Zehra Yilmaz,
• Ozlem Sen,
• Melis Emanet,
• Emine Kazanc and
• Mustafa Çulha

Beilstein J. Nanotechnol. 2015, 6, 84–102, doi:10.3762/bjnano.6.9

• and it might be worthwhile to further investigate it [71]. BNNT-grafted, poly(glycidyl methacrylate) and polystyrene brushes were prepared via atom transfer radical polymerization [72]. The resulting nanocomposite material was characterized using FTIR, TGA, SEM and TEM. The TEM images clearly show the

Poly(styrene)/oligo(fluorene)-intercalated fluoromica hybrids: synthesis, characterization and self-assembly

• Giuseppe Leone,
• Francesco Galeotti,
• William Porzio,
• Guido Scavia,
• Luisa Barba,
• Gianmichele Arrighetti,
• Giovanni Ricci,
• Chiara Botta and
• Umberto Giovanella

Beilstein J. Nanotechnol. 2014, 5, 2450–2458, doi:10.3762/bjnano.5.254

• powders by synchrotron radiation XRD. Successively, the hybrids are dispersed in poly(styrene) through in situ polymerization. Such a procedure allows us to synthesize the materials from solution, to achieve solid films, and to characterize them by optical and morphologic techniques. The polymeric films

• (styrene) (PS) matrix by in situ thermal polymerization. Such a procedure allowed us to process the materials as solid films and to characterize them by optical, structural, and morphologic analyses. In addition, we explored the possibility of organizing these materials in ordered honeycomb structures

• material in solution, we believed that an intriguing strategy would be to use a polymer as dispersing agent. Our previous results [8][9][10] caused us to regard the in situ polymerization as a potent tool to improve the intimate mixing between the polymer and the inorganic component. Thus, we synthesized