The role of ligands in coinage-metal nanoparticles for electronics

• Ioannis Kanelidis and
• Tobias Kraus

Beilstein J. Nanotechnol. 2017, 8, 2625–2639, doi:10.3762/bjnano.8.263

• silver nitrate in the presence of poly(vinylpyrrolidone) (PVP, Figure 2) and sodium bromide. The nanobars formed when bromide ions etched the multiply twinned seeds, promoted the formation of single crystal seeds, and initiated anisotropic growth [68]. Longer silver nanowires grew from multiply twinned

• nanoparticles by the reduction of silver nitrate in the presence of PVP. The twin boundaries served as active sites for the addition of silver atoms as the strong interaction between PVP and the sides of the initially formed nanorod allowed preferential diffusion of the silver atoms to the ends of the nanorods

• nanorods [70]. Single crystalline gold nanoplates were prepared in water from hydrogen tetrachloroaurate and PVP using sodium citrate as reducing agent. The authors believe that low sodium citrate concentrations create small numbers of nuclei and that the remaining gold ions attach laterally on the nuclei

Synthesis and characterization of noble metal–titania core–shell nanostructures with tunable shell thickness

• Bartosz Bartosewicz,
• Marta Michalska-Domańska,
• Malwina Liszewska,
• Dariusz Zasada and
• Bartłomiej J. Jankiewicz

Beilstein J. Nanotechnol. 2017, 8, 2083–2093, doi:10.3762/bjnano.8.208

• poly(sodium 4-styrenesulfonate) (PSS) [49], mercaptoundecanoic acid [38][39], 1-ethenylpyrrolidin-2-one (PVP) [33][41], or hydroxypropyl cellulose [45][46][47]. In addition, in some studies, an adhesion layer was formed on the metal NP surface in order to better control the TiO2 shell growth [48]. The

Synthesis and catalytic application of magnetic Co–Cu nanowires

• Lijuan Sun,
• Xiaoyu Li,
• Zhiqiang Xu,
• Kenan Xie and
• Li Liao

Beilstein J. Nanotechnol. 2017, 8, 1769–1773, doi:10.3762/bjnano.8.178

• the foundation for expanding their application to industrial catalysis. All chemicals were of analytical reagent grade and used without any further purification. CoCl2·6H2O, EDTA-2Na, CuSO4·5H2O, PVP, NaOH, N2H4·H2O, H2PtCl6·6H2O and C2H5OH were purchased from Chengdu Kelong Reagent Co., Ltd (China

• measured by a magnetometer. The detailed synthetic process for the Co–Cu nanowires was as follows. First, 0.14 g of CoCl2·6H2O and 0.22 g of EDTA-2Na were dispersed in 60 mL of deionized water in a 100 mL polytetrafluoroethylene (PTFE) beaker. Then 0.18 g of PVP was added to the reaction solution. The pH

• because they originated from the silicon wafer substrate, PVP and H2PtCl6·6H2O, respectively. Moreover, the elemental mapping profiles (Figure 4c,d) of Co and Cu further proved the presence of Co and Cu as well as their uniform distribution patterns. The magnetic hysteresis loop of bimetallic Co–Cu

Near-infrared-responsive, superparamagnetic Au@Co nanochains

• Varadee Vittur,
• Arati G. Kolhatkar,
• Shreya Shah,
• Irene Rusakova,
• Dmitri Litvinov and
• T. Randall Lee

Beilstein J. Nanotechnol. 2017, 8, 1680–1687, doi:10.3762/bjnano.8.168

• polyvinylpyrrolidone (PVP), Au@Co nanochains with a hollow interior are formed. Using this new methodology, we were able to shift the optical extinction of the generated nanoparticles to the near-infrared (NIR) region (about 900 nm), which is significantly higher than the maximum of 700 nm observed previously for

• this replacement reaction, it is likely that nucleation of the reduced Au atoms led to small Au particles that eventually grew into a thin Au shell covering the cobalt nanoparticles. At the same time, because of its extended polymeric chain structure, PVP, which was present as a colloidal stabilizer

• the hollow nanostructure. As noted above, PVP is widely used as a colloidal stabilizer to inhibit the aggregation of metal nanoparticles such as gold [49][50][51][52], silver [53][54], platinum [55][56][57], palladium [46][57][58][59], nickel [60][61], and cobalt [62][63]. To verify this hypothesis in

Parylene C as a versatile dielectric material for organic field-effect transistors

• Tomasz Marszalek,
• Maciej Gazicki-Lipman and
• Jacek Ulanski

Beilstein J. Nanotechnol. 2017, 8, 1532–1545, doi:10.3762/bjnano.8.155

• polymer insulators bear much higher application potential in organic transistor technology. There are only few commercial dielectric polymer materials that meet the requirements: poly(methylmethacrylate) (PMMA) [42], polyvinylphenol (PVP) [43], amorphous fluoropolymer (CYTOP®) [44] and poly-p-xylylene

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

• performed either in water or in air, and afterwards stabilization by polyvinylpyrrolidone (PVP) in dispersion. Air-sonicated MWCNTs allowed for a smooth polymerization reaction, resulting in 20 wt % solids content (s.c.), stable and film-forming latexes with up to 1 wt % MWCNTs incorporated. Important

• purchased from IoLiTec Nanomaterials Co. (98.5%, Germany). Polyvinylpyrrolidone (PVP) with molar mass of 10,000 g·mol−1 was purchased from Sigma-Aldrich (99%). Potassium persulfate (KPS) was used as an initiator and purchased from Fluka. Sodium dodecyl sulfate (SDS) from Sigma-Aldrich (99%) and stearyl

• pretreated by sonication in air, after which they were dispersed in water in presence of PVP. The procedure for sonication in air was as follow: 0.35 g of MWCNTs were placed into a 50 mL beaker that had a magnetic stirrer. An ultrasound tip (Branson 450 instrument, Danbury, CT) was introduced into the beaker

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

• acid and cetyltrimethylammonium bromide (CTAB) were supplied by Shanghai Chemical Regents Co. (Shanghai, China). Additionally, polyvinyl pyrrolidone (PVP) (Mw = 1300000) was purchased from Tianjin Bodi Chemical Reagent Co., Ltd. (Tianjin, China). All chemicals were used as received without further

• purification. Preparation of the spinning solution 0.5 g PVP and 0.3 g CTAB were firstly dissolved into 6.5 g ethanol and 0.4 g acetic acid followed by vigorously stirring to form a homogeneous solution. Subsequently, 1 g paraffin oil and stoichiometric amounts of TBT with different TBT/paraffin oil ratios (w

• decomposition process could be divided into three steps. The first step occurred between 25 to 150 °C and can be attributed to the evaporation of residual solvent and water. The second step from 160 to 370 °C corresponds to the major decomposition process of long molecular chains of PVP and paraffin oil as well

Optical response of heterogeneous polymer layers containing silver nanostructures

• Miriam Carlberg,
• Florent Pourcin,
• Olivier Margeat,
• Judikaël Le Rouzo,
• Gérard Berginc,
• Rose-Marie Sauvage,
• Jörg Ackermann and
• Ludovic Escoubas

Beilstein J. Nanotechnol. 2017, 8, 1065–1072, doi:10.3762/bjnano.8.108

• colloidal solutions range from 390 to 1300 nm. The non-absorbing, transparent polymer matrix poly(vinylpyrrolidone) (PVP) was chosen because of its suitable optical and chemical properties. The optical studies of the layers include spectrophotometry and spectroscopic ellipsometry measurements, which provide

• control the absorption of thin film layers by embedding different NPs. When included in polymer thin film layers (such as poly(vinylpyrrolidone) (PVP)), the plasmon resonance wavelengths of the NPs are red-shifted with respect to the resonance wavelengths in water. This environment dependence can easily

• with computer simulations and transmission electron microscopy (TEM) imaging. Spectrophotometer and spectroscopic ellipsometry measurements of the PVP host matrix validated its non-absorbing and transparent properties. Spectroscopic ellipsometry measurements of the heterogeneous layers of nanospheres

The longstanding challenge of the nanocrystallization of 1,3,5-trinitroperhydro-1,3,5-triazine (RDX)

• Florent Pessina and
• Denis Spitzer

Beilstein J. Nanotechnol. 2017, 8, 452–466, doi:10.3762/bjnano.8.49

• synthesis of 30 nm RDX in a pH 7-stabilized solution. For such sizes and even at that pH, agglomeration and Ostwald ripening occur. Therefore, to avoid the degradation of the nanoparticles, a polymer coating (PEI or poly(vinylpyrrolidone) (PVP)) is necessary. It should be mentioned that no subsequent

• chemical interaction was also found from IR and Raman spectra. The high versatility of the SFE permits the processing of liquid (poly(ethylene glycol) (PEG) 400) and solid (PVP 40k) polymers to tune the RDX particle size distribution from the nanometer to the micrometer scale with controlled shapes [121

• ]. The smallest particle diameter obtained was at 160 nm with a spherical morphology. Adding 0.05 wt % of PVP decreased the size of RDX by 34%, from around 500 nm to 320 nm, but also significantly improved the spheric shape. Additionally, all the synthesized RDX samples were less sensitive, especially

Template-controlled piezoactivity of ZnO thin films grown via a bioinspired approach

• Nina J. Blumenstein,
• Fabian Streb,
• Stefan Walheim,
• Thomas Schimmel,
• Zaklina Burghard and
• Joachim Bill

Beilstein J. Nanotechnol. 2017, 8, 296–303, doi:10.3762/bjnano.8.32

• several washing steps in Milli-Q water. ZnO mineralization For all solutions, methanol (BASF, VLSI selectipur) was used as solvent. Stock solutions with 34.02 mm Zn(CH3COO)2∙2H2O (Sigma-Aldrich, ≥99.0%), 25.71 mm poly(vinylpyrrolidone) (PVP, Sigma-Aldrich, Mw ≈ 10,000 g mol−1, batch BCBJ4889V) and 75 mm

• tetraethylammonium hydroxide (TEAOH, Sigma-Aldrich, 1.5 m in methanol) were prepared. The PVP and zinc acetate solutions were mixed and the TEAOH was added drop-wise with a peristaltic pump under gentle stirring. The final composition was [Zn2+] = 11.34 mm, [PVP] = 8.57 mm and [TEAOH] = 25 mm. The coated wafers were

Functionalized platinum nanoparticles with surface charge trigged by pH: synthesis, characterization and stability studies

• Giovanna Testa,
• Laura Fontana,
• Iole Venditti and
• Ilaria Fratoddi

Beilstein J. Nanotechnol. 2016, 7, 1822–1828, doi:10.3762/bjnano.7.175

• solvothermal techniques are well favored for the synthesis of PtNPs, together with sol–gel methods [17]. They give rise to colloidal suspensions although a fine control of the size, dispersity and the surface functionalization is quite difficult to reach. Poly(N-vinyl-2-pyrrolidone) (PVP) has been used as a

Surface-enhanced infrared absorption studies towards a new optical biosensor

• Lothar Leidner,
• Julia Stäb,
• Jennifer T. Adam and
• Günter Gauglitz

Beilstein J. Nanotechnol. 2016, 7, 1736–1742, doi:10.3762/bjnano.7.166

• used in the experiments were polyvinylpyrrolidone (PVP) stabilized spherical silver nanoparticles (AgNP) with a diameter of 51 nm in aqueous suspension, AgNP content 0.01% (w/w) and PVP content 0.2% (w/w). The nanoparticle suspension was used as delivered. Amplification of water OH-stretching band

Role of RGO support and irradiation source on the photocatalytic activity of CdS–ZnO semiconductor nanostructures

• Suneel Kumar,
• Rahul Sharma,
• Vipul Sharma,
• Gurunarayanan Harith,
• Vaidyanathan Sivakumar and
• Venkata Krishnan

Beilstein J. Nanotechnol. 2016, 7, 1684–1697, doi:10.3762/bjnano.7.161

• permanganate (KMnO4) and hydrogen peroxide (H2O2) were purchased from Merck. Zinc chloride (ZnCl2), sodium hydroxide (NaOH), cadmium acetate dihydrate (Cd(OOCCH3)2·2H2O), sodium sulfide (Na2S), ammonia solution and methyl orange were also supplied by Merck. Polyvinyl pyrrolidone (PVP) used in synthesis was

• ) (0.2 M) was prepared in deionized water. To this solution, 20 mL of sodium sulfide (Na2S) solution (0.2 M) was added dropwise under continuous stirring. After 10 min of stirring, 0.5 g of PVP was added as capping agent under vigorous stirring. The pH value of the solution was maintained at around 10 by

• of CdS NP also reveal the presence of O–H stretching vibrations of adsorbed water molecules on its surface. The peak at 1550 cm−1 is attributed to the C–N stretching vibration of the PVP monomer, which was used as capping agent [53]. The 1404 cm−1 peak corresponds to the C–H bond of PVP [54]. CdS–ZnO

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

• Qingxin Nie Zengyuan Pang Hangyi Lu Yibing Cai Qufu Wei Key Laboratory of Eco-Textiles, Ministry of Education, Jiangnan University, 214122 Wuxi, Jiangsu, China 10.3762/bjnano.7.122 Abstract Indium nitrate/polyvinyl pyrrolidone (In(NO3)3/PVP) composite nanofibers were synthesized via

• 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

• morphology of In(NO3)3/PVP, In2O3/PANI composite nanofibers and pure PANI were investigated by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and current–voltage (I–V) measurements. The gas sensing properties

Tunable longitudinal modes in extended silver nanoparticle assemblies

• Serene S. Bayram,
• Klas Lindfors and
• Amy Szuchmacher Blum

Beilstein J. Nanotechnol. 2016, 7, 1219–1228, doi:10.3762/bjnano.7.113

• pentagonal silver crystals into silver wires when capped with polyvinylpyrrolidone (PVP) in the polyol synthesis. Their calculations showed that at high concentrations of PVP, the energy difference between the (100) and (111) facets is sufficiently reduced, eliciting a strain restriction, which in turn

Preparation of alginate–chitosan–cyclodextrin micro- and nanoparticles loaded with anti-tuberculosis compounds

• Albert Ivancic,
• Fliur Macaev,
• Fatma Aksakal,
• Veaceslav Boldescu,
• Serghei Pogrebnoi and
• Gheorghe Duca

Beilstein J. Nanotechnol. 2016, 7, 1208–1218, doi:10.3762/bjnano.7.112

• the delivery of a celecoxib–hydroxypropyl-β-cyclodextrin–PVP complex [3] and for the controlled release of insulin after oral delivery [4][5]. Since these were mainly administered through the digestive tract, their sizes were only determined by bioavailability, and not by aerosol stability as in the

Manufacturing and investigation of physical properties of polyacrylonitrile nanofibre composites with SiO₂, TiO₂ and Bi₂O₃ nanoparticles

• Tomasz Tański,
• Wiktor Matysiak and
• Barbara Hajduk

Beilstein J. Nanotechnol. 2016, 7, 1141–1155, doi:10.3762/bjnano.7.106

• acid) (PLA), poly(butylene succinate) (PBS), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), poly(vinylidene difluoride) (PVBF), poly(vinylpyrrolidone) PVP, poly(acrylonitrile) (PAN)) reinforced with particles of SiO2, TiO2 and Bi2O3, particularly in thin layers, are very attractive because of

Synthesis of cobalt nanowires in aqueous solution under an external magnetic field

• Xiaoyu Li,
• Lijuan Sun,
• Hu Wang,
• Kenan Xie,
• Qin Long,
• Xuefei Lai and
• Li Liao

Beilstein J. Nanotechnol. 2016, 7, 990–994, doi:10.3762/bjnano.7.91

• pressures, cobalt nanowires were synthesized by chemical reduction in aqueous solution with the assistance of polyvinylpyrrolidone (PVP) as surfactant under moderate conditions for the first time, while an external magnetic field of 40 mT was applied. Uniform linear cobalt nanowires with relatively smooth

• surfaces and firm structure were obtained and possessed an average diameter of about 100 nm with a coating layer of PVP. By comparison, the external magnetic field and PVP were proven to have a crucial influence on the morphology and the size of the synthesized cobalt nanowires. The prepared cobalt

• under moderate conditions [12]. In this research, with polyvinylpyrrolidone (PVP) as surfactant, uniform linear cobalt nanowires with a mean diameter of about 100 nm were synthesized in aqueous solution under an external magnetic field at low temperature and atmosphere pressure for the first time. All

Surface coating affects behavior of metallic nanoparticles in a biological environment

• Darija Domazet Jurašin,
• Marija Ćurlin,
• Ivona Capjak,
• Tea Crnković,
• Marija Lovrić,
• Michal Babič,
• Daniel Horák,
• Ivana Vinković Vrček and
• Srećko Gajović

Beilstein J. Nanotechnol. 2016, 7, 246–262, doi:10.3762/bjnano.7.23

• −38.5 ± 2.9, −27.8 ± 1.9 and −26.9 ± 1.1 mV, respectively. For AgNPs coated with uncharged molecules; PVP, Tween 20 and Brij 35, we expected a ζ-potential close to zero. However, all of the three mentioned AgNPs were characterized by slightly negative ζ-potentials ranging from −6 to −19 mV. Since we

• ligands such as PVP and BSA provide additional steric hindrances. Our results, in accordance with previously published data [48], imply that CIT, PVP and BSA provided colloidal stability for AgNPs irrespective to the type of surface interactions. It is interesting that we have recently observed [49] a

• -potential imparted by adsorbed , a residual side product from AgNPs synthesis. In addition, PVPAgNPs were stabilized by steric repulsion of PVP molecules. However, anions were also attached to the BrijAgNPs and TweenAgNPs coatings, but adsorption of Tween 20 and Brij 35 surfactants to the AgNPs surfaces

Chemical bath deposition of textured and compact zinc oxide thin films on vinyl-terminated polystyrene brushes

• Nina J. Blumenstein,
• Caroline G. Hofmeister,
• Peter Lindemann,
• Cheng Huang,
• Johannes Baier,
• Andreas Leineweber,
• Stefan Walheim,
• Christof Wöll,
• Thomas Schimmel and
• Joachim Bill

Beilstein J. Nanotechnol. 2016, 7, 102–110, doi:10.3762/bjnano.7.12

• methanol (VLSI Grade, J. T. Baker) with concentrations of 20, 40 and 85 mM, respectively, were mixed. The reaction solution was prepared by mixing the stock solutions in a volume ratio of PVP/ZnAc2/TEAOH 3:2:2. Thereby, the TEAOH solution was added drop wise to the PVP–ZnAc2 mixture with a peristaltic pump

Controlled graphene oxide assembly on silver nanocube monolayers for SERS detection: dependence on nanocube packing procedure

• Martina Banchelli,
• Bruno Tiribilli,
• Roberto Pini,
• Luigi Dei,
• Paolo Matteini and
• Gabriella Caminati

Beilstein J. Nanotechnol. 2016, 7, 9–21, doi:10.3762/bjnano.7.2

• synthesized through a polyol synthesis, in the presence of poly(vinylpyrrolidone) (PVP) as a stabilizing agent, adopting an established literature protocol [35]. The resulting nanocube samples were mainly monodisperse with 45 nm average size and contained only a negligible fraction of Ag rods and irregular

• presence of the PVP polymer surrounding the nanoparticles. These features also warrant a successful transfer of the film from the water subphase to the solid support (Supporting Information File 1, Figure S2), fast reorganization of the nanocubes at the interface when the material is transferred to the

• transfer was obtained also at 0.5 mN/m although with low nanocube density. Such behaviour, reported also by other authors for mixed AgNC/phospholipid systems [40], is likely due to the stabilizing effect of PVP cushion capping the surface of the nanocubes. Optical microscopy in reflection mode of LB

Green and energy-efficient methods for the production of metallic nanoparticles

• Mitra Naghdi,
• Mehrdad Taheran,
• Satinder K. Brar,
• M. Verma,
• R. Y. Surampalli and
• J. R. Valero

Beilstein J. Nanotechnol. 2015, 6, 2354–2376, doi:10.3762/bjnano.6.243

• , they produced spherical Ag NPs with an average diameter of 26 nm, and polydispersity of 2.3%. They also investigated the capability of different ionic and non-ionic surfactants and also polyethylene glycol (PEG) and polyvinylpyrrolidone (PVP) in surface modification and stabilization of Ag NPs produced

• by reaction of AgNO3 and D-maltose. According to their results, sodium dodecyl sulfate (SDS), polyoxyethylenesorbitan monooleate (Tween 80) and PVP (Mw = 360000) were superior stabilizers for aggregation of Ag NPs [64]. Tai et al. used starch and glucose to reduce AgNO3 to Ag NPs in a spinning disk

Nanoscale rippling on polymer surfaces induced by AFM manipulation

• Mario D’Acunto,
• Franco Dinelli and
• Pasqualantonio Pingue

Beilstein J. Nanotechnol. 2015, 6, 2278–2289, doi:10.3762/bjnano.6.234

• different periodicities depending on the T value at which the experiment is carried out and with respect to the Tg values of the two components. Maas et al. [50] have conducted an experimental work on polysterene/polyvinylpyrrolidone (PS/PVP) copolymer films where the composition ratio is varied and the

• wear patterns reveal the different proportions of PS and PVP within the single molecules. Finally, Aoike et al. [51] have also reported studies on random copolymers. Part 2: Theoretical modelling Once observed and described, like any other physical phenomenon, the formation of nanoripples should be

NanoE-Tox: New and in-depth database concerning ecotoxicity of nanomaterials

• Katre Juganson,
• Angela Ivask,
• Irina Blinova,
• Monika Mortimer and
• Anne Kahru

Beilstein J. Nanotechnol. 2015, 6, 1788–1804, doi:10.3762/bjnano.6.183

• 15% uncoated. ENMs were most often modified with citrate (31% of all coatings) and polyvinylpyrrolidone (PVP; 24% of all coatings) (Figure 4a). The high percentage of coated NPs in the database can be explained by the fact that nanosilver which constituted 35% of the database entries is frequently

• functionalised with different coatings, polyvinylpyrrolidone (PVP) and citrate being the most widely used. A parameter closely related to NP surface properties is surface charge. It has been shown that positively charged ENMs tend to attach to the cellular surface that is negatively charged and these

In situ SU-8 silver nanocomposites

• Søren V. Fischer,
• Basil Uthuppu and
• Mogens H. Jakobsen

Beilstein J. Nanotechnol. 2015, 6, 1661–1665, doi:10.3762/bjnano.6.168

• bought from Sigma-Aldrich. Luviskol® VA 64, a poly(vinylpyrrolidone-co-vinyl acetate) (PVP/VA) mixture was kindly gifted by BASF. Method 1 g of PVP/VA and 0.1 g of silver nitrate is dissolved in 50 mL of absolute ethanol. 0.02 g of sodium borohydride and 0.2 g of PVP/VA dissolved in 10 mL of absolute