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Search for "functionalization" in Full Text gives 394 result(s) in Beilstein Journal of Nanotechnology. Showing first 200.
Review on nanoparticles and nanostructured materials: history, sources, toxicity and regulations
Beilstein J. Nanotechnol. 2018, 9, 1050–1074, doi:10.3762/bjnano.9.98
Electro-optical interfacial effects on a graphene/π-conjugated organic semiconductor hybrid system
Beilstein J. Nanotechnol. 2018, 9, 963–974, doi:10.3762/bjnano.9.90
- of graphene-based devices, SAM surface functionalization is employed for both doping level control and work function tuning [14][15][16]. The present work brings these two fronts together by investigating a graphene/retinoic acid (RA) – a π-conjugated organic semiconductor – hybrid system and its
- surface), G (green color), Gf and RA (brown – dark and blue – illuminated). It is clear in Figure 4f that, upon RA functionalization, the surface potential of a graphite microplate decreases. This provides a signature of p-type doping of graphene, as follows: the work function φ of any material is given
- of Gf, which results from the p-doping of Gf induced by RA functionalization. The data in Figure 5 clearly indicate that RA self-assembled monolayers present a larger surface potential difference compared to graphite microplate (in agreement with the photo-assisted EFM experiments in Figure 4). In
Heavy-metal detectors based on modified ferrite nanoparticles
Beilstein J. Nanotechnol. 2018, 9, 762–770, doi:10.3762/bjnano.9.69
- agreement, which also confirms the successful fabrication of requested structures. Infrared spectroscopy All samples were measured by IR spectroscopy to see if the surface of nanoparticles changes after core modification and surface functionalization. This method was also expected to serve as a reference
- unmodified one) in the range of 1393–1591 cm−1, which indicates the presence of C–C bonds in the rings of PA and SA [30]. The spectra after functionalization with 3-PPA or 16-PHDA show the presence of signals around 1060 and 1105 cm−1, which proves the presence of P–O and P–O–Fe stretching bonds [31]. Bands
- hint that local Fe surrounding becomes maghemite-like. In Figure 5B, the spectra of SA-modified Mn0.5Fe2.5O4 nanoparticles after the adsorption of different ions are depicted. The comparison of spectra collected in Figure 5B with unmodified particles (Figure 5A) indicates that surface functionalization
The effect of atmospheric doping on pressure-dependent Raman scattering in supported graphene
Beilstein J. Nanotechnol. 2018, 9, 704–710, doi:10.3762/bjnano.9.65
- designed to operate on the basis of undoped properties of graphene; on the other hand, the adsorption of certain functional groups, for example, can be used as a constituent part of the methods of graphene functionalization [4]. At the same time, graphene layers on substrates are necessary for
- , graphene functionalization techniques, and taking into account adsorption effects during nanoelectronic device engineering. Experimental Graphene was synthesized on Cu foil at 1020 °C by a chemical vapor deposition (CVD) method using a mixture of CH4 of 40 sccm and H2 of 10 sccm. Cu foil (Alfa Aesar
Cyclodextrin-assisted synthesis of tailored mesoporous silica nanoparticles
Beilstein J. Nanotechnol. 2018, 9, 693–703, doi:10.3762/bjnano.9.64
- functionalization-induced changes in the CD structure. The solubility of CD molecules greatly varies depending on the CD structure. Pristine CDs are poorly soluble molecules due to the presence of strong intermolecular hydrogen bonding in the crystal state (e.g., the solubility of β-CD in water is 18.5 g/L) [22
- structure [23][24]. The aggregation is mainly governed by hydrogen bonds between the hydroxyl moieties. After the functionalization with HP motifs, no significant aggregation was observed for partially substituted HP-β-CDs at low concentration (12 mM) [25]. It is thus expected that the HP-γ-CD incorporation
Tuning adhesion forces between functionalized gold colloidal nanoparticles and silicon AFM tips: role of ligands and capillary forces
Beilstein J. Nanotechnol. 2018, 9, 660–670, doi:10.3762/bjnano.9.61
- higher than on their nanoparticle counterparts, the dependance on functional groups remained the same. Keywords: adhesion; AFM; gold; nanoparticle functionalization; nanoparticles; Introduction Adhesion is a complex combination of various interfacial forces such as capillary, electrostatic and vdW
- surface treatment. One approach is the functionalization of the surfaces with various ligands. For instance, grafting a thin molecular film with hydrophobic tail groups on a surface, formed by self-assembly process, prevents the formation of nano- or microdroplets of water on the treated sample, or
- between Au particles and silicon substrates. Furthermore, Langbein et al. stated that the vdW attraction between two surfaces is only affected by their outer layers, if the separation of the surfaces is lower or in the same range as the thickness of the outer layer [22]. As a result, functionalization of
Single-step process to improve the mechanical properties of carbon nanotube yarn
Beilstein J. Nanotechnol. 2018, 9, 545–554, doi:10.3762/bjnano.9.52
- . Covalent bonding among the tubes can be obtained via simultaneous functionalization and crosslinking [19]. Possible strategies for enhancing the friction between CNTs include modifying CNT surfaces through physical processes (e.g., condensing the tubes under high pressure) [16], chemical processes [20][21
- a dose of 27 kGy. The low dose of 27 kGy was chosen for this preliminary investigation because only functionalization on the MWNT powder surface was desired. The aim of this preliminary study was to verify the conversion of AN to PAN on the MWNT powder surface under e-beam irradiation. An aqueous
- . investigated the functionalization of vapor-grown carbon fibers (VGCFs), via gamma and e-beam radiation processes using acrylic acid as a source of oxygen functional groups, which enhanced the dispersion of VGCFs in water [33]. Unlike CNTs, VGCFs have a unique morphology, a tubular structure with the sidewalls
Colloidal solution of silver nanoparticles for label-free colorimetric sensing of ammonia in aqueous solutions
Beilstein J. Nanotechnol. 2018, 9, 499–507, doi:10.3762/bjnano.9.48
- absorption spectra in a concentration-dependent manner and catalyses the formation of silver nanoparticles. Size, shape and surface functionalization of the nanoparticles can strongly influence the spectral trend of the plasmon band of the silver nanoparticles [28][29]. As evident from Figure 1, the plasmon
Engineering of oriented carbon nanotubes in composite materials
Beilstein J. Nanotechnol. 2018, 9, 415–435, doi:10.3762/bjnano.9.41
- anisotropy, is achieved for the engineering of cardiac [21], muscle [22] and nerve tissues [23]. Finally, CNT properties can be fine-tuned upon chemical functionalization. However, the latter characteristic needs to be well-balanced in order to prevent degradation of the CNT properties [24][25][26]. The
Anchoring of a dye precursor on NiO(001) studied by non-contact atomic force microscopy
Beilstein J. Nanotechnol. 2018, 9, 242–249, doi:10.3762/bjnano.9.26
- , Switzerland 10.3762/bjnano.9.26 Abstract The properties of metal oxides, such as charge-transport mechanisms or optoelectronic characteristics, can be modified by functionalization with organic molecules. This kind of organic/inorganic surface is nowadays highly regarded, in particular, for the design of
A robust AFM-based method for locally measuring the elasticity of samples
Beilstein J. Nanotechnol. 2018, 9, 1–10, doi:10.3762/bjnano.9.1
- of the Young’s modulus of the FDTS monolayer. Effect of tip functionalization on the SiOx elasticity peak of the SAM sample The proximity of the peaks of FDTS and SiOx holes can be explained by the fact that during scanning, some material of FDTS has gathered around the tip, so that the relatively
- AFM scan on silicon. Since our sample consists of a perforated Teflon-like monolayer, the cantilever tip is most likely constantly functionalized with a thin layer of FDTS. This leads to the observed soft elasticity in- and outside the holes. The stability of this functionalization during the scan can
- 1.2 nm deep holes. Due to the functionalization of the cantilever tip by SAM molecules, a similar stiffness is measured inside and outside the holes. Finally, the measured value of the storage modulus of 478.5 ± 0.5 MPa, which is close to the value for bulk PTFE (500 MPa), can be used as an estimation
L-Lysine-grafted graphene oxide as an effective adsorbent for the removal of methylene blue and metal ions
Beilstein J. Nanotechnol. 2017, 8, 2680–2688, doi:10.3762/bjnano.8.268
- strong cohesive interactions of graphene basal planes and edges have also caused some difficulties in attaining its optimal performance. Hence, the functionalization of graphene has been extensively developed to further improve its properties and broaden its potential application, such as loading of
- defects and π–π interactions on the graphene basal planes and edges can enhance the adsorption capacities for pollutants [3][20]. We inferred that organic molecules modifying graphene might improve their adsorption capabilities. For instance, Swager et al. reported the surface functionalization of
Patterning of supported gold monolayers via chemical lift-off lithography
Beilstein J. Nanotechnol. 2017, 8, 2648–2661, doi:10.3762/bjnano.8.265
- regions containing Au–alkanethiolates appeared bright in fluorescence microscopy images (Figure 2). Using this straightforward functionalization and visualization method, we investigated patterns of lifted-off Au monolayers on PDMS as substrates for DNA recognition. Upon hybridization of dye-labeled
- functionalization chemistries of Au. Experimental Fabricating patterned polydimethylsiloxane stamps Stamps with topographic features were prepared as previously described [85]. The Sylgard® 184 silicone elastomer kits were purchased from Dow Corning (Midland, MI, USA). The elastomer base and curing agent were mixed
The role of ligands in coinage-metal nanoparticles for electronics
Beilstein J. Nanotechnol. 2017, 8, 2625–2639, doi:10.3762/bjnano.8.263
- ligands are employed during synthesis to determine geometry [2][8], to control colloidal stability [5][26][27][28], to expand the solubility range through end-functionalization [29], or to influence the electro-optical features [26][30] of the resulting nanoparticles (NPs). They can act as cross-linkers
Inelastic electron tunneling spectroscopy of difurylethene-based photochromic single-molecule junctions
Beilstein J. Nanotechnol. 2017, 8, 2606–2614, doi:10.3762/bjnano.8.261
- particularly promising because of the negligible change of molecular length between the two isomers (i.e., open and closed forms) and the possibility for further chemical functionalization [13][14]. The isomerization upon illumination with appropriate wavelengths tunes the electronic structure of the molecules
Amplified cross-linking efficiency of self-assembled monolayers through targeted dissociative electron attachment for the production of carbon nanomembranes
Beilstein J. Nanotechnol. 2017, 8, 2562–2571, doi:10.3762/bjnano.8.256
- high thermal stability [1][2][3]. Depending on the fabrication method, the choice of precursor molecules and functionalization type, such membranes have great potential for a wide variety of applications [2]. In recent years, protocols and procedures have been developed to produce functional CNMs by
Direct writing of gold nanostructures with an electron beam: On the way to pure nanostructures by combining optimized deposition with oxygen-plasma treatment
Beilstein J. Nanotechnol. 2017, 8, 2530–2543, doi:10.3762/bjnano.8.253
- Figure 5b, indicate that the O-plasma cleaning exposed some of the embedded Au nanocrystallites to the exterior. Such purified patterned nanostructures are deemed very suitable for further functionalization, e.g., for immobilization of biomolecules or similar applications where having clean Au surfaces
- functionalization. Conclusion In summary, we investigated a FEBID experimental parameter subspace, aiming to fabricate 2D and 3D nanostructures with a high Au content, starting from a common metal-organic precursor, Me2-Au-tfac. In the first instance, we realized vertical free-standing FEBID Au nanopillars having a
- functionalization, which is highly desired for a range of applications in nanotechnology. Experimental The samples were prepared by FEBID of Au inside a custom-modified Zeiss Leo 1530VP SEM. The microscope was equipped with a home-made gas injection system containing dimethylgold(III)-trifluoroacetylacetonate
Synthesis of metal-fluoride nanoparticles supported on thermally reduced graphite oxide
Beilstein J. Nanotechnol. 2017, 8, 2474–2483, doi:10.3762/bjnano.8.247
- reactive sites for the nucleation and growth of metal nanoparticles. The nucleation and growth mechanism depends on the degree of oxygen functionalization at the graphene surface sheets, such that no nanoparticles are obtained at totally reduced graphene surfaces [7][79]. TRGO is generally regarded as a
- good base material for obtaining highly loaded nanoparticle–graphene hybrid materials, because of its surface functionalization [80]. A distinct possibility is the formation of hydrogen bonds between the metal-fluoride nanoparticles and the hydroxyl groups at the TRGO surface. Batteries based on
Strategy to discover full-length amyloid-beta peptide ligands using high-efficiency microarray technology
Beilstein J. Nanotechnol. 2017, 8, 2446–2453, doi:10.3762/bjnano.8.243
- features of the used system [27]. An additional advantage is the ease of implementing on it consolidated coating methods for the hosting of biomolecules. In this work, for peptide immobilization in a microarray format, we propose one of the most common functionalization methods (an epoxysilane) although
- different kinds of functionalization processes can be used [28]. To validate the new platform with suitable control experiments, we used two different peptides (i.e., KLVFF and Semax), investigating their ability to bind monomeric Aβ. Residues encompassing the domain 16–20 of the Aβ peptide may act as a
Involvement of two uptake mechanisms of gold and iron oxide nanoparticles in a co-exposure scenario using mouse macrophages
Beilstein J. Nanotechnol. 2017, 8, 2396–2409, doi:10.3762/bjnano.8.239
- diagnostic and therapeutic applications [4]. There is convincing evidence that the physico-chemical properties of NPs, such as size, shape, material, and surface functionalization, strongly influence uptake and intracellular trafficking of NPs [5][6][7]. The uptake of NPs occurs via endocytotic pathways
In situ controlled rapid growth of novel high activity TiB2/(TiB2–TiN) hierarchical/heterostructured nanocomposites
Beilstein J. Nanotechnol. 2017, 8, 2116–2125, doi:10.3762/bjnano.8.211
- these exposed atoms could serve as high activity positions and might be used in future research in the fields of proton exchange membrane fuel cells, surface chemical modification and functionalization [18][19]. Moreover, the internal and external components were TiB2 and TiN, respectively. The crystal
- highly active material could possibly be further used in the research fields of proton exchange membrane fuel cells, structural and functional performance integrated composite ceramics and/or films, surface chemical modification and functionalization. Another point worth noting is that the detailed
Magnetic properties of optimized cobalt nanospheres grown by focused electron beam induced deposition (FEBID) on cantilever tips
Beilstein J. Nanotechnol. 2017, 8, 2106–2115, doi:10.3762/bjnano.8.210
- magnetic nanostructures have been produced in last years by the focused electron beam induced deposition (FEBID) technique [1][2]. The extensive list of nanostructures includes: (a) planar deposits in the shape of Hall bars for sensing purposes [3][4][5][6]; (b) magnetic nanopillars for functionalization
A systematic study of the controlled generation of crystalline iron oxide nanoparticles on graphene using a chemical etching process
Beilstein J. Nanotechnol. 2017, 8, 2017–2025, doi:10.3762/bjnano.8.202
- were found to have diameters in the range of 9 ± 4 nm after this annealing procedure (Figure 5). To summarize, functionalization of CVD-derived graphene with iron oxide nanoparticles is possible using customized etchants and/or additional processing techniques. The number of iron oxide particles in
- subdividing the etching chamber into two connected individual compartments. Using this modified chemical etching process, an additional post-processing to remove polymer residues from graphene is not required. We further investigated functionalization of graphene with iron oxide nanoparticles by using
- hydrochloric solutions of iron(III) chloride as the etchant in the modified transfer process. A controlled functionalization with iron(II) oxide nanoparticles is possible by adjusting the ratio of copper to etchant, the concentration of iron(III) chloride and weight percent of hydrochloric acid employed. The
Identifying the nature of surface chemical modification for directed self-assembly of block copolymers
Beilstein J. Nanotechnol. 2017, 8, 1972–1981, doi:10.3762/bjnano.8.198
- silicon wafer, left in the Figure) and the block copolymer domains. The first DSA (two steps) process uses electron beam lithography (EBL) [12] on a poly(methyl methacrylate) (PMMA) resist with a subsequent substrate functionalization with oxygen plasma of the uncovered areas (top of Figure 1). The two
- the oxygen plasma functionalization. Conversely, when the sample is cooled down in nitrogen, PS does not undergo oxidation. As a consequence, such a sample is slightly affine to PS before functionalization. When chemical guiding stripes are defined on this substrate by oxygen plasma exposure (see
- of the polymer brush layer were analysed, we investigated the effect of the functionalization upon exposure to oxygen plasma. Figure 3c shows the C 1s HAXPES spectrum taken with 2020 eV photons of the sample cooled in nitrogen after the oxygen plasma treatment. The comparison with Figure 3a evidences
Carbon nano-onions as fluorescent on/off modulated nanoprobes for diagnostics
Beilstein J. Nanotechnol. 2017, 8, 1878–1888, doi:10.3762/bjnano.8.188
- 10.3762/bjnano.8.188 Abstract Multishell fullerenes, known as carbon nano-onions (CNOs), have emerged as a platform for bioimaging because of their cell-penetration properties and minimal systemic toxicity. Here, we describe the covalent functionalization of CNOs with a π-extended distyryl-substituted
- procedure [25][26]. The condensation with dimethylaminobenzaldehyde led to the NIR-BODIPY derivative 3. The surface functionalization of 5 nm pristine CNOs (p-CNOs), synthetized by thermal annealing of d-NDs, was obtained by an oxidation process using a 3 M solution of nitric acid under reflux condition
- (BODIPY 3) is the switched-off form while the protonated form (BODIPY 4) is the switched-on form. The successful functionalization of CNOs with BODIPY 3 was confirmed by photoemission studies. Upon photoexcitation at 680 nm, fluo-CNOs-1a (Figure 2) exhibited a maximum emission (λem) at 768 nm, while fluo
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