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Search for "adsorption" in Full Text gives 744 result(s) in Beilstein Journal of Nanotechnology. Showing first 200.

Design of surface nanostructures for chirality sensing based on quartz crystal microbalance

  • Yinglin Ma,
  • Xiangyun Xiao and
  • Qingmin Ji

Beilstein J. Nanotechnol. 2022, 13, 1201–1219, doi:10.3762/bjnano.13.100

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  • based on noncovalent interactions, including hydrogen bonding, metal coordination, van der Waals forces, π–π interaction, and electrostatic interaction. Moreover, the structural “fitting” effect may also have distinct adsorption behaviors for enantiomers. Therefore, the design of effective chiral
  • layers, composed of biomolecules, polymers, supramolecular assemblies, and functional organic hybrids have been successfully constructed on the surface of QCM electrodes. According to frequency shifts of QCM upon adsorption, detection efficiencies of various selectors for chiral analytes could be
  • in the pharmaceutical industry. It has been taken as a model molecule to verify the “proof-of-principle” concept for chiral recognition [28]. Kim and co-workers fabricated ʟ-phenylalanine (ʟ-Phe)-modified QCM sensor and used vapor diffusion molecular assembly (VDMA) to study the chiral adsorption of
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Published 27 Oct 2022

Application of nanoarchitectonics in moist-electric generation

  • Jia-Cheng Feng and
  • Hong Xia

Beilstein J. Nanotechnol. 2022, 13, 1185–1200, doi:10.3762/bjnano.13.99

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  • regions of high concentration to regions of low concentration. This enhances the transfer of electric charges and improves the electrical energy output [61]. Under natural conditions, a film material with a certain thickness will induce a difference in water concentration due to its poor adsorption
  • voltages of 0.115, 0.52, 0.5, and 0.71 V, respectively. As shown in Figure 8a, the existence of this natural concentration difference has been experimentally proved in a work regarding protein nanowires. In organic materials, in addition to the difference in natural adsorption capacity to construct
  • self-powered generators driven by natural water evaporation“, article no. 104502, Copyright Elsevier (2020). This content is not subject to CC BY 4.0. (d) A cross-sectional SEM image of the phase-engineered MoS2 film with a film thickness of 4.6 µm. (e) The adsorption and desorption process of ions
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Published 25 Oct 2022

Rapid fabrication of MgO@g-C3N4 heterojunctions for photocatalytic nitric oxide removal

  • Minh-Thuan Pham,
  • Duyen P. H. Tran,
  • Xuan-Thanh Bui and
  • Sheng-Jie You

Beilstein J. Nanotechnol. 2022, 13, 1141–1154, doi:10.3762/bjnano.13.96

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  • are different approaches to mitigate NO pollution, including catalyst/non-catalyst [4], oxidation [5], bioprocesses [6], adsorption [7], absorption [8], and non-thermal plasma technologies [9]. Photocatalytic oxidation is considered a promising approach due to its ability to degrade various air
  • the dosage of catalysts was 0.2 g for all experiments. Before each catalytic experiment, 0.2 g of the sample was dispersed in 10 mL of DI water, evaporated at 80 °C, and placed in the dark to achieve adsorption–desorption equilibrium. Finally, the sample was illuminated by a Xenon lamp (300 W) for 30
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Published 18 Oct 2022

Green synthesis of zinc oxide nanoparticles toward highly efficient photocatalysis and antibacterial application

  • Vo Thi Thu Nhu,
  • Nguyen Duy Dat,
  • Le-Minh Tam and
  • Nguyen Hoang Phuong

Beilstein J. Nanotechnol. 2022, 13, 1108–1119, doi:10.3762/bjnano.13.94

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  • technologies have been proposed to remove organic pollutants from water, including coagulation coupled with sedimentation, biological processes, membrane filtration, adsorption, advanced oxidation, catalysis, and photocatalysis [1][2][3]. Using semiconductors as photocatalysts has been a widely studied
  • in the dark for 30 min to equilibrate the adsorption. Subsequently, the suspensions were illuminated by a 30 W LED or an 18 W high-pressure mercury lamp. The light source was fixed at a distance of 20 cm from the surface of the reactor. After fixed illumination times, 5 mL was withdrawn and
  • centrifuged at 6000 rpm to measure the dye concentrations. The dye concentration was analyzed by UV–vis spectroscopy (Hitachi U2900) with maximum adsorption wavelengths of MB and MO of 664 nm and 464 nm, respectively [29][30]. The degradation efficiency was calculated using Equation 3. where c0 is the initial
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Published 07 Oct 2022

Recent advances in green carbon dots (2015–2022): synthesis, metal ion sensing, and biological applications

  • Aisha Kanwal,
  • Naheed Bibi,
  • Sajjad Hyder,
  • Arif Muhammad,
  • Hao Ren,
  • Jiangtao Liu and
  • Zhongli Lei

Beilstein J. Nanotechnol. 2022, 13, 1068–1107, doi:10.3762/bjnano.13.93

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  • confirmed the catalytic activity of the product. Adsorption of heavy ions from water samples was investigated to find the activity on the surface of the product, and it was found that the mentioned CDs can remove Cd2+ ions by 37% and Pb2+ ion by 75% from the water sample [111]. Watermelon juice-based N-CDs
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Published 05 Oct 2022

Biomimetic chitosan with biocomposite nanomaterials for bone tissue repair and regeneration

  • Se-Kwon Kim,
  • Sesha Subramanian Murugan,
  • Pandurang Appana Dalavi,
  • Sebanti Gupta,
  • Sukumaran Anil,
  • Gi Hun Seong and
  • Jayachandran Venkatesan

Beilstein J. Nanotechnol. 2022, 13, 1051–1067, doi:10.3762/bjnano.13.92

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  • -hydroxybutyrate) composites generates a hydrophilic environment which promotes cell motility, adhesion, and protein adsorption. Furthermore, the mixture enhances the surface roughness of the composites, stimulating bone cells to attach to the surface [108]. The different characteristics of the 3D porous collagen
  • wettability and protein adsorption which can facilitate osteogenesis [129]. Biomaterials such as chitosan and its composites containing bioactive metals draw much attention in tissue engineering and regenerative applications. Chitosan-based composites are now being studied in wound healing, bone and cartilage
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Published 29 Sep 2022

Spindle-like MIL101(Fe) decorated with Bi2O3 nanoparticles for enhanced degradation of chlortetracycline under visible-light irradiation

  • Chen-chen Hao,
  • Fang-yan Chen,
  • Kun Bian,
  • Yu-bin Tang and
  • Wei-long Shi

Beilstein J. Nanotechnol. 2022, 13, 1038–1050, doi:10.3762/bjnano.13.91

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  • remove CTC existing in the aquatic environment. Up to now, various technologies, including adsorption, hydrolysis, and biodegradation, have been applied in the removal of pollutants from water [5][6][7][8]. Owing to the relatively complicated treatment, high cost, and possible secondary pollution, these
  • cavities, and excellent thermal stability [20][21]. These advantages make it appalling to adsorption [22], gaseous capture/separation [23], sensing [24], and drug release applications [25]. Moreover, some MOFs can be excited under UV or visible light and exhibit light harvesting properties due to ligand
  • of a CTC solution with an initial concentration of 20 mg/L and stirred in the dark for 30 min to reach adsorption–desorption equilibrium. Then, the photocatalytic reaction was initiated by a 300 W xenon lamp with a 420 nm cut-off filter. At 20 min intervals, 4 mL of the sample was taken out and
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Published 28 Sep 2022

Influence of water contamination on the sputtering of silicon with low-energy argon ions investigated by molecular dynamics simulations

  • Grégoire R. N. Defoort-Levkov,
  • Alan Bahm and
  • Patrick Philipp

Beilstein J. Nanotechnol. 2022, 13, 986–1003, doi:10.3762/bjnano.13.86

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  • simulation conditions used in this work, the adsorption of water favours the formation of defects in silicon by mixing hydrogen and oxygen atoms into the substrate. The sputtering yield of silicon is not significantly changed by the contamination, but the fraction of hydrogen and oxygen atoms that is
  • sample. The water molecules were equilibrated using the ReaxFFOH(2017) [24] potential in a fully periodic space using the NPT ensemble. Since the adsorption of water molecules on a surface is a random process, the orientation of the molecules could freely evolve. Snapshots of water equilibration can be
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Published 21 Sep 2022

Bioselectivity of silk protein-based materials and their bio-inspired applications

  • Hendrik Bargel,
  • Vanessa T. Trossmann,
  • Christoph Sommer and
  • Thomas Scheibel

Beilstein J. Nanotechnol. 2022, 13, 902–921, doi:10.3762/bjnano.13.81

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  • cells but to even display antiviral attachment properties [58]. Superhydrophobic surfaces inspired by the Lotus-effect® (>150° contact angle) have been found to diminish bacterial adhesion due to reduced protein surface adsorption [59][60][61]. Superhydrophobicity relies on the combination of chemical
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Published 08 Sep 2022

Solar-light-driven LaFexNi1−xO3 perovskite oxides for photocatalytic Fenton-like reaction to degrade organic pollutants

  • Chao-Wei Huang,
  • Shu-Yu Hsu,
  • Jun-Han Lin,
  • Yun Jhou,
  • Wei-Yu Chen,
  • Kun-Yi Andrew Lin,
  • Yu-Tang Lin and
  • Van-Huy Nguyen

Beilstein J. Nanotechnol. 2022, 13, 882–895, doi:10.3762/bjnano.13.79

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  • pollutants, such as adsorption, coagulation, filtration, and chemical and biochemical oxidation [10][11]. Advanced oxidation processes (AOPs) have recently attracted attention due to their simple operation, low cost, and potentially high effectiveness. AOPs are the technologies that use various chemical
  • presented as black, as shown in Figure 5b. They successfully increased the absorption efficiency of visible light and utilized more visible light effectively. In order to determine the specific surface area, pore size, and pore volume of the prepared perovskite oxides, the analysis of nitrogen adsorption
  • various photocatalysts prepared at pH 0 or pH 7 The standard concentration of MB aqueous solution was prepared at 20 ppm. Various LaFexNi1−xO3 perovskite oxides prepared at pH 0 were examined for dark adsorption and photocatalytic degradation. First, dark adsorption was not significant for all perovskite
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Published 05 Sep 2022

DNA aptamer selection and construction of an aptasensor based on graphene FETs for Zika virus NS1 protein detection

  • Nathalie B. F. Almeida,
  • Thiago A. S. L. Sousa,
  • Viviane C. F. Santos,
  • Camila M. S. Lacerda,
  • Thais G. Silva,
  • Rafaella F. Q. Grenfell,
  • Flavio Plentz and
  • Antero S. R. Andrade

Beilstein J. Nanotechnol. 2022, 13, 873–881, doi:10.3762/bjnano.13.78

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  • ) functionalization with ZIKV60 aptamers. In this experiment, we used 100 mM PBS as electrolyte for gating. The π-conjugated units of the pyrene-modified ZIKV60 aptamers transfer electrons to graphene, resulting in the left-shift of the graphene transfer curve because of the aptamer adsorption. Several studies
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Published 02 Sep 2022

Self-assembly of C60 on a ZnTPP/Fe(001)–p(1 × 1)O substrate: observation of a quasi-freestanding C60 monolayer

  • Guglielmo Albani,
  • Michele Capra,
  • Alessandro Lodesani,
  • Alberto Calloni,
  • Gianlorenzo Bussetti,
  • Marco Finazzi,
  • Franco Ciccacci,
  • Alberto Brambilla,
  • Lamberto Duò and
  • Andrea Picone

Beilstein J. Nanotechnol. 2022, 13, 857–864, doi:10.3762/bjnano.13.76

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  • aspect is the electronic coupling between the molecules and the metallic substrate. In this case, the key parameter is the adsorption energy (Ea), which is defined as the energy required to desorb a molecule from the surface. A high Ea is characteristic of molecules chemisorbed on the substrate, where a
  • relevant charge transfer between the overlayer and the substrate occurs. In contrast, a low Ea is characteristic of physisorbed molecules, for which the adsorption is mediated by the weak van der Waals interaction with the substrate. Chemisorption is the typical scenario for molecules stabilized on
  • ascribed to charge transfer from ZnTPP to the Fe(001)–p(1 × 1)O substrate. When 1 ML of C60 is added, the variation of the work function is within the experimental error, indicating a negligible charge transfer on the surface region upon C60 adsorption. The electronic properties of C60 adsorbed on ZnTPP
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Published 30 Aug 2022

Temperature and chemical effects on the interfacial energy between a Ga–In–Sn eutectic liquid alloy and nanoscopic asperities

  • Yujin Han,
  • Pierre-Marie Thebault,
  • Corentin Audes,
  • Xuelin Wang,
  • Haiwoong Park,
  • Jian-Zhong Jiang and
  • Arnaud Caron

Beilstein J. Nanotechnol. 2022, 13, 817–827, doi:10.3762/bjnano.13.72

Graphical Abstract
  • drop is not disrupted during application onto a substrate. In contrast, when the oxide skin breaks, new oxide forms at the solid–liquid interface with a substrate, which results in adhesion. Also, the wetting of a liquid Ga–In alloy has been related to the adsorption energy of gallium on three
  • different substrates (steel, gold, and Al) [13], with the wetting becoming better as the adsorption energy of gallium onto the substrate becomes more negative. In the case of Fe and Cu substrates, it was observed that liquid gallium reacts with the substrate to form an intermetallic layer at the gallium
  • the meniscus flow of the eutectic Ga–In–Sn melt upon retraction, the adsorption of a thin water layer is likely to modify the surface energy of the liquid neck upon pulling and affect the above results. The analysis of the interfacial energy from AFM adhesion measurements is thus complicated by the
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Published 23 Aug 2022

Recent advances in nanoarchitectures of monocrystalline coordination polymers through confined assembly

  • Lingling Xia,
  • Qinyue Wang and
  • Ming Hu

Beilstein J. Nanotechnol. 2022, 13, 763–777, doi:10.3762/bjnano.13.67

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  • creating meso–macro channels without destroying most of the micropores. This can be achieved by removing emulsion networks from the single crystal [116]. The obtained HKUST-1 crystals contained bimodal or trimodal pores, which facilitated adsorption and enabled a fast Friedländer reaction. When the
  • demonstrated in millimeter-sized superstructures formed by ZIF-8 or UiO-66 [131]. Owing to the porous structure of the monocrystalline coordination polymers. The dielectric constant of the particles may be changed upon adsorption of molecules such as organic vapor. This can lead to a change of the structural
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Published 12 Aug 2022

Hierarchical Bi2WO6/TiO2-nanotube composites derived from natural cellulose for visible-light photocatalytic treatment of pollutants

  • Zehao Lin,
  • Zhan Yang and
  • Jianguo Huang

Beilstein J. Nanotechnol. 2022, 13, 745–762, doi:10.3762/bjnano.13.66

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  • using a reference to the peak of the surface adventitious carbon (284.8 eV) in the high-resolution spectrum of the C 1s region. The N2 adsorption−desorption isotherms were recorded at −196 °C on a Micromeritics ASAP 2020 analyzer, while the specific surface area and pore distribution curve were
  • 5.0 cm from the quartz tube reactor. The photocatalyst (10.0 mg) was dispersed in the pollutant solution (20.0 mL, 10.0 mg·L−1) and stirred in the dark for 1 h to guarantee the adsorption−desorption equilibrium. Then, the visible light was switched on, and the suspension containing photocatalyst and
  • irradiation for t hours, after the achievement of the adsorption−desorption equilibrium, and at the initial moment (10.0 mg·L−1), respectively. The photocatalytic stabilities of the cellulose-derived Bi2WO6/TiO2-NT nanocomposites on the photocatalytic reduction of Cr(VI) or degradation of RhB were confirmed
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Published 04 Aug 2022

A nonenzymatic reduced graphene oxide-based nanosensor for parathion

  • Sarani Sen,
  • Anurag Roy,
  • Ambarish Sanyal and
  • Parukuttyamma Sujatha Devi

Beilstein J. Nanotechnol. 2022, 13, 730–744, doi:10.3762/bjnano.13.65

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  • the scan rate suggests a surface-confined diffusion-controlled electrocatalytic process [21]. The slope of log Ipc as a function of log ν is 0.611 (>0.5), which confirms an adsorption-based reduction of PT on the modified electrode surface (Figure 7B). The reduction peak potential was shifted towards
  • on PT sensing in environmental samples. Other interfering OP (acephate, chlorpyrifos) and organochloride (dicofol, lindane) pesticides also did not significantly affect the response current of PT reduction as they have different redox potential and adsorption potential on the modified electrode
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Published 28 Jul 2022

Modeling a multiple-chain emeraldine gas sensor for NH3 and NO2 detection

  • Hana Sustkova and
  • Jan Voves

Beilstein J. Nanotechnol. 2022, 13, 721–729, doi:10.3762/bjnano.13.64

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  • gradient approximated (GGA) Perdew–Burke–Ernzerhof (PBE) exchange–correlation functional was used. Guo et al. [5] investigated the graphene/polyaniline adsorption energy of NH3, CO, NO, and H2 using DFT and molecular dynamics computations. From this, graphene/PANI is highly sensitive to NH3 in comparison
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Published 26 Jul 2022

Nanoarchitectonics of the cathode to improve the reversibility of Li–O2 batteries

  • Hien Thi Thu Pham,
  • Jonghyeok Yun,
  • So Yeun Kim,
  • Sang A Han,
  • Jung Ho Kim,
  • Jong-Won Lee and
  • Min-Sik Park

Beilstein J. Nanotechnol. 2022, 13, 689–698, doi:10.3762/bjnano.13.61

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  • the Zn/Co ratio during synthesis. The composite with higher Zn content has a larger BET surface area and micropore volume but a smaller mesopore volume, as compared in Figure 5c and Supporting Information File 1, Table S1. According to the adsorption–desorption hysteresis curves, the Zn1Co4–C/CNT
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Published 21 Jul 2022

Comparative molecular dynamics simulations of thermal conductivities of aqueous and hydrocarbon nanofluids

  • Adil Loya,
  • Antash Najib,
  • Fahad Aziz,
  • Asif Khan,
  • Guogang Ren and
  • Kun Luo

Beilstein J. Nanotechnol. 2022, 13, 620–628, doi:10.3762/bjnano.13.54

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  • that a local micro-convection is induced in the base fluid due to the Brownian motion of nanoparticles, which increases both mixing and heat transport within the nanofluid [16][17]. Later, several studies demonstrated that interactions between liquid atoms and nanoparticles (i.e., a liquid adsorption
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Published 07 Jul 2022

Sodium doping in brookite TiO2 enhances its photocatalytic activity

  • Boxiang Zhuang,
  • Honglong Shi,
  • Honglei Zhang and
  • Zeqian Zhang

Beilstein J. Nanotechnol. 2022, 13, 599–609, doi:10.3762/bjnano.13.52

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  • magnetically stirred for 30 min in the dark to equilibrate the adsorption and desorption of MB on the surface of the crystallites. After switching on the UV light, samples were periodically collected and centrifuged. The concentration of the MB solution was analyzed based on the characteristic absorption peak
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Published 05 Jul 2022

Stimuli-responsive polypeptide nanogels for trypsin inhibition

  • Petr Šálek,
  • Jana Dvořáková,
  • Sviatoslav Hladysh,
  • Diana Oleshchuk,
  • Ewa Pavlova,
  • Jan Kučka and
  • Vladimír Proks

Beilstein J. Nanotechnol. 2022, 13, 538–548, doi:10.3762/bjnano.13.45

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  • substituents compared to PHEG-Tyr nanogel [25]. This assumption is also supported by the DH dependence (Figure 3a) showing a DH maximum at pH 7.4. Adsorption and release of BSA and AAT Next, optimization studies of in vitro loading of 125I-radiolabeled BSA as a model protein and its release from PHEG-Tyr and
  • of BSA (pI 4.7) and, thus, BSA adsorption is driven by electrostatic and hydrophobic interactions [30][31]. PHEG-Tyr nanogel was incubated with three different 125I-radiolabeled BSA concentrations (1, 0.75, and 0.5 mg/mL), and the loading efficiency was found to be low, that is, 2.1% (21 µg/mL), 1.9
  • interaction [35][36]. Our observation indicates that the adsorption of 125I-radiolabeled BSA onto Nα-Lys-NG is mainly driven by hydrophobic interaction. At higher initial concentrations of 125I-radiolabeled BSA, both polypeptide nanogels, Nα-Lys-NG and PHEG-Tyr, are quickly saturated and unable to adsorb
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Published 22 Jun 2022

Zinc oxide nanostructures for fluorescence and Raman signal enhancement: a review

  • Ioana Marica,
  • Fran Nekvapil,
  • Maria Ștefan,
  • Cosmin Farcău and
  • Alexandra Falamaș

Beilstein J. Nanotechnol. 2022, 13, 472–490, doi:10.3762/bjnano.13.40

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  • a higher adsorption of analyte molecules, increasing the EF from 106 (before) to 108 (after hydrogenation) [43]. The charge transfer effect was probably increased as well since the hydrogenation introduced lattice defects that could alter the energy band structure of ZnO, promoting charge separation
  • promoted strong light confinement, and the increased number of adsorption sites due to the branched ZnO nanostructures. Despite the fact that ZnO is a non-plasmonic semiconductor material, it can elicit a degree of SERS effect via chemical enhancement of atomic vibrational modes of the analyte. Kim et al
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Published 27 May 2022

Investigation of electron-induced cross-linking of self-assembled monolayers by scanning tunneling microscopy

  • Patrick Stohmann,
  • Sascha Koch,
  • Yang Yang,
  • Christopher David Kaiser,
  • Julian Ehrens,
  • Jürgen Schnack,
  • Niklas Biere,
  • Dario Anselmetti,
  • Armin Gölzhäuser and
  • Xianghui Zhang

Beilstein J. Nanotechnol. 2022, 13, 462–471, doi:10.3762/bjnano.13.39

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  • ][9]. Self-assembled monolayers (SAMs) are ordered molecular assemblies formed by the adsorption of amphiphilic organic molecules on a solid surface [10][11][12]. Self-assembled monolayers are model systems that enable a fundamental understanding of self-organization and provide a versatile path to
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Published 25 May 2022

A chemiresistive sensor array based on polyaniline nanocomposites and machine learning classification

  • Jiri Kroutil,
  • Alexandr Laposa,
  • Ali Ahmad,
  • Jan Voves,
  • Vojtech Povolny,
  • Ladislav Klimsa,
  • Marina Davydova and
  • Miroslav Husak

Beilstein J. Nanotechnol. 2022, 13, 411–423, doi:10.3762/bjnano.13.34

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  • arrays were exposed to various relative humidity levels ranging from 20% to 80% (Figure 10). The obtained results show a decreasing sensor response with increasing RH% value. This change in response toward relative humidity is due to the adsorption of water molecules and an increase of charge
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Published 27 Apr 2022

Electrostatic pull-in application in flexible devices: A review

  • Teng Cai,
  • Yuming Fang,
  • Yingli Fang,
  • Ruozhou Li,
  • Ying Yu and
  • Mingyang Huang

Beilstein J. Nanotechnol. 2022, 13, 390–403, doi:10.3762/bjnano.13.32

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  • et al. [33] used molecular dynamics to compare the adsorption energies of GR-Au and GR-GR structures. The GR-GR structure has a higher adsorption energy of 307 mJ/m2. Mizuta et al. [7][35] assumed that the use of a GR-GR electrode structure could avoid the uncontrollable microscale interactions
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Published 12 Apr 2022
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