Fabrication of nano/microstructures for SERS substrates using an electrochemical method

• Jingran Zhang,
• Tianqi Jia,
• Xiaoping Li,
• Junjie Yang,
• Zhengkai Li,
• Guangfeng Shi,
• Xinming Zhang and
• Zuobin Wang

Beilstein J. Nanotechnol. 2020, 11, 1568–1576, doi:10.3762/bjnano.11.139

• spots decreases. Sivashanmugan et al. [32] employed FIB technology to prepare nanostructures on silicon surfaces, which were then coated with Au and Ag films to generate SERS substrates. The enhancement factor range of R6G using the substrate was between 2.62 × 106 and 1.74 × 107. Gao et al. [33

• a KCl-saturated Ag/AgCl rod are used as the working, counter, and reference electrodes, respectively. Using this approach, Au/TiO2 nanocomposites formed on Pt substrates yielded a SERS enhancement factor of 1.8 × 108 for R6G molecules [34]. Chang et al. [35] fabricated different Ag nanostructures on

• to fabricate roughened Ag substrates. In this system, the limit of detection for R6G with SERS was 2 × 10−8 mol·L−1. Based on a ORC method, Chen et al. [37] created hybrid Au–AuOx with reverse rates of 200, 100, 50, 25, and 5 mV/s. The highest enhancement factor observed with R6G in this system was

Adsorption and self-assembly of porphyrins on ultrathin CoO films on Ir(100)

• Feifei Xiang,
• Tobias Schmitt,
• Marco Raschmann and
• M. Alexander Schneider

Beilstein J. Nanotechnol. 2020, 11, 1516–1524, doi:10.3762/bjnano.11.134

• homogeneous contrast develops in Figure 4d. Such compact assemblies were previously observed for the case of the non-metalated 2H-DPP compound on Ag(110) [24] and on Au(111) [22], but, for example, not on Cu(111) [23]. For the assembly on 1BL CoO, the distance between the phenyl rings is a little larger than

• forms compact islands on the 2BL film when the molecules are deposited at approx. 300 K or when the system is annealed to that temperature (Figure 6a). The appearance of 2 on the 2BL film is very similar to that on Ag(111) and allows for an identification of individual molecules in the compact

Controlling the electronic and physical coupling on dielectric thin films

• Philipp Hurdax,
• Michael Hollerer,
• Larissa Egger,
• Georg Koller,
• Xiaosheng Yang,
• Anja Haags,
• Serguei Soubatch,
• Frank Stefan Tautz,
• Mathias Richter,
• Alexander Gottwald,
• Peter Puschnig,
• Martin Sterrer and
• Michael G. Ramsey

Beilstein J. Nanotechnol. 2020, 11, 1492–1503, doi:10.3762/bjnano.11.132

• (6P) on ultrathin MgO(100) films supported on Ag(100) is reported. By deliberately changing the work function of the MgO(100)/Ag(100) system, it is shown that the charge transfer (electronic coupling) into the 6P molecules can be controlled, and 6P monolayers with uncharged molecules (Schottky–Mott

• Pacchioni et al. [4][5][6] and either inferred or observed for adsorbates ranging from metal atoms [7][8] and small molecules [9][10] to larger π-conjugated molecules [11][12][13]. This phenomenon has been comprehensively analyzed for 5A on epitaxial MgO(100)/Ag(100), in which orbital-resolved STM and

• )/Ag(100) work function after MgO film growth (ΦMgO) by changing the composition at the dielectric–metal interface without changing its surface [16][17][18][19], it has been recently shown that two distinct adsorption regimes exist [20]. On films with a high ΦMgO, all molecules in the ML remain neutral

Self-assembly and spectroscopic fingerprints of photoactive pyrenyl tectons on hBN/Cu(111)

• Domenik M. Zimmermann,
• Knud Seufert,
• Luka Ðorđević,
• Tobias Hoh,
• Sushobhan Joshi,
• Tomas Marangoni,
• Davide Bonifazi and
• Willi Auwärter

Beilstein J. Nanotechnol. 2020, 11, 1470–1483, doi:10.3762/bjnano.11.130

• -ylethynyl substituents have been used to steer and control the self-assembly on hBN/Cu(111), including the formation of dense-packed arrays and intricate kagome networks. The resulting structures deviate in part from the assemblies previously studied on Ag(111) [48]. Additionally, the hBN decoupling layer

• section, we will put forward a comparative discussion of the self-assembly of pyridin-4-ylethynyl-functionalized pyrenes on hBN/Cu(111) and on Ag(111) [48]. The molecular density of tetrapyridylpyrene 1 in arrays on hBN/Cu(111) was higher compared to Ag(111) (ρtetra/hBN = 0.41 molecules/nm2 vs ρtetra/Ag

• hBN/Cu(111) and Ag(111), the separation along the unit cell vector a was clearly reduced on hBN, reflecting the minimum energy interdigitation configuration, determined by basic molecular mechanics modeling for two modules of 1 in the gas phase. Thus, we tentatively assigned the higher packing density

Antimicrobial metal-based nanoparticles: a review on their synthesis, types and antimicrobial action

• Matías Guerrero Correa,
• Fernanda B. Martínez,
• Cristian Patiño Vidal,
• Camilo Streitt,
• Juan Escrig and
• Carol Lopez de Dicastillo

Beilstein J. Nanotechnol. 2020, 11, 1450–1469, doi:10.3762/bjnano.11.129

• allows for nanoparticles to be synthesized directly from a metal source. Jung et al., for example, obtained Ag NPs in various sizes, ranging from 6 to 21 nm. However, this technique has the disadvantage of consuming a significant amount of energy and it requires a large lab space for the experimental

• different materials in a fast, safe, and environmentally friendly way. This technique allows for the synthesis of Ag [27], CuO [28], and MgO [29] NPs with sizes ranging from 1 to 25 nm. In addition, with this technique it is possible to control the geometry of the nanoparticles in order to obtain squared

• irradiation time. For example, while Tan et al. [31] obtained spherical silver nanoparticles, Zhou et al. [32] obtained plate-like triangles. Another method used is the pulsed laser ablation technique which is used to synthesize colloidal solutions of Ag [33], Au [34], MgO [35], and ZnO [36] NPs, among others

Wafer-level integration of self-aligned high aspect ratio silicon 3D structures using the MACE method with Au, Pd, Pt, Cu, and Ir

• Mathias Franz,
• Romy Junghans,
• Paul Schmitt,
• Adriana Szeghalmi and
• Stefan E. Schulz

Beilstein J. Nanotechnol. 2020, 11, 1439–1449, doi:10.3762/bjnano.11.128

• layer for the wet etching of silicon. The MACE process has been extensively studied over the last decade [13][14][15][16]. In theory, the process works with a wide range of noble metals. The main focus in research has been set on the noble metals gold (Au) and silver (Ag) [2][17][18][19]. Other studies

Protruding hydrogen atoms as markers for the molecular orientation of a metallocene

• Linda Laflör,
• Michael Reichling and
• Philipp Rahe

Beilstein J. Nanotechnol. 2020, 11, 1432–1438, doi:10.3762/bjnano.11.127

• ionised derivates calculations yielded rotational barrier values of up to 1.4 eV [19]. From this class of molecules we investigate the ferrocene derivate 1,1’-ferrocene dicarboxylic acid (FDCA), a ferrocene functionalised with two carboxylic acid moieties. This molecule has been analysed before on Ag(111

• FDCA molecule to the tip with the carbonyl moiety facing the surface. This would be in line with earlier NC-AFM experiments of naphthalene tetracarboxylic diimide (NTCDI) adsorbed on Ag-terminated silicon surfaces [37]. In the latter case, the observation of submolecular contrast similar to images

Impact of fluorination on interface energetics and growth of pentacene on Ag(111)

• Qi Wang,
• Meng-Ting Chen,
• Antoni Franco-Cañellas,
• Bin Shen,
• Thomas Geiger,
• Holger F. Bettinger,
• Frank Schreiber,
• Ingo Salzmann,
• Alexander Gerlach and
• Steffen Duhm

Beilstein J. Nanotechnol. 2020, 11, 1361–1370, doi:10.3762/bjnano.11.120

• ) on Ag(111) via X-ray standing waves (XSW), low-energy electron diffraction (LEED) as well as ultraviolet and X-ray photoelectron spectroscopy (UPS and XPS). XSW revealed that the adsorption distances of F4PEN in (sub)monolayers on Ag(111) were 3.00 Å for carbon atoms and 3.05 Å for fluorine atoms

• . The F4PEN monolayer was essentially lying on Ag(111), and multilayers adopted π-stacking. Our study shed light not only on the F4PEN–Ag(111) interface but also on the fundamental adsorption behavior of fluorinated pentacene derivatives on metals in the context of interface energetics and growth mode

• charge transfer from the substrate [9][28]. This can be explained by the repulsive interaction of the fluorine atoms with the substrate, which leads to much larger vertical adsorption heights of PFP compared to PEN in monolayers on Cu(111) [9]. Ag(111) represents an intermediate case [55] with weak

Growth of a self-assembled monolayer decoupled from the substrate: nucleation on-command using buffer layers

• Robby Reynaerts,
• Kunal S. Mali and
• Steven De Feyter

Beilstein J. Nanotechnol. 2020, 11, 1291–1302, doi:10.3762/bjnano.11.113

• formed at the solution–solid interface, is a more of routine occurrence than an exception. Such structurally diverse monolayers are typically formed on solid substrates such as highly oriented pyrolytic graphite (HOPG), graphene, and metals such as Cu, Ag and Au and have been characterized using scanning

Ultrasensitive detection of cadmium ions using a microcantilever-based piezoresistive sensor for groundwater

• Dinesh Rotake,
• Anand Darji and
• Nitin Kale

Beilstein J. Nanotechnol. 2020, 11, 1242–1253, doi:10.3762/bjnano.11.108

• . Results of the SAM detecting cadmium ions The proposed microfluidic platform provides real-time monitoring of Cd(II) in groundwater. We performed the experiment using the coating of cysteamine thiol with cross-linked ᴅʟ-glyceraldehyde (Cys-DL-GC). We have already discussed that the methods based on Au/Ag

Hybridization vs decoupling: influence of an h-BN interlayer on the physical properties of a lander-type molecule on Ni(111)

• Maximilian Schaal,
• Takumi Aihara,
• Marco Gruenewald,
• Felix Otto,
• Jari Domke,
• Roman Forker,
• Hiroyuki Yoshida and
• Torsten Fritz

Beilstein J. Nanotechnol. 2020, 11, 1168–1177, doi:10.3762/bjnano.11.101

• indicative of a strong electronic interaction of first-layer molecules with the Ni(111) substrate. A similar broadening was observed for DBP on Ag(111), where a mixing of the molecular frontier orbitals with the metal bands of the substrate was concluded [26]. After about 0.25 monolayer equivalents (MLE

• ordered DBP on h-BN/Ni(111), suitable coincidences with the lowest substrate orders are the on-line coincidences (1, 2), (−1, −2), (−2, 1), and (2, −1). A comparison with reported lateral structures of DBP on Ag(111) [34] and Au(111) [33] shows very similar adsorbate lattice parameters except for the unit

• the LT-STM measurements, we concluded that the DBP molecules adopt a herringbone structure similar to DBP on Ag(111) and Au(111). Furthermore, we observed that the low work function of h-BN/Ni(111) decreases upon DBP deposition down to a value of 3.45(2) eV for the highly ordered DBP layer on h-BN/Ni

Scanning tunneling microscopy and spectroscopy of rubrene on clean and graphene-covered metal surfaces

• Karl Rothe,
• Alexander Mehler,
• Nicolas Néel and
• Jörg Kröger

Beilstein J. Nanotechnol. 2020, 11, 1157–1167, doi:10.3762/bjnano.11.100

• (Figure 1c) where one diagonal pair of phenyl groups would appear higher than the other. Such a configuration was indeed observed for a closed monolayer of C42H28 on Ag(100) [24]. However, it is difficult to infer geometric heights from STM images due to variations in the local density of states. Moreover

• superimposed molecule sketch visualizes this assignment. For some molecules the apparent height of all four phenyl groups is similar, while others exhibit a pair of diagonal phenyl groups appearing higher than the other pair, similar to previous findings on Ag(100) [24]. This observation is compatible with the

• of the molecular backbone of C42H28 is not limited to low-temperature depositions. It was likewise observed for room-temperature deposition on low-index Cu surfaces [22][36] and Ag(100) [24]. The STM image in Figure 4c shows the influence of the Au(111) reconstruction on the C42H28 assembly

Revealing the local crystallinity of single silicon core–shell nanowires using tip-enhanced Raman spectroscopy

• Marius van den Berg,
• Ardeshir Moeinian,
• Arne Kobald,
• Yu-Ting Chen,
• Anke Horneber,
• Steffen Strehle,
• Alfred J. Meixner and
• Dai Zhang

Beilstein J. Nanotechnol. 2020, 11, 1147–1156, doi:10.3762/bjnano.11.99

• antenna. This nanoantenna is typically made by chemical etching of a thin Ag or Au wire or by evaporating a Ag or Au thin film on AFM tips. The tip works like an optical antenna when it is brought as close as a few nanometers to the sample surface and when it is illuminated with a tightly focused laser

Photothermally active nanoparticles as a promising tool for eliminating bacteria and biofilms

• Mykola Borzenkov,
• Piersandro Pallavicini,
• Angelo Taglietti,
• Laura D’Alfonso,
• Maddalena Collini and
• Giuseppe Chirico

Beilstein J. Nanotechnol. 2020, 11, 1134–1146, doi:10.3762/bjnano.11.98

• results regarding antibacterial activity. The advances in the field of nanomaterials exhibiting antibacterial activity are well summarized in recent reviews [1][7][8][9]. In particular, the antibacterial properties of silver nanoparticles (Ag NPs) and Ag-NP-based polymeric materials are the most

• intensively studied within the broad spectrum of existing nanomaterials [10][11][12][13][14][15]. However, the low stability (even at physiological pH levels) and the potential toxicity of Ag NPs limit their application [7][16]. Moreover, the results regarding the efficiency of Ag NPs in preventing biofilm

• formation are controversial as the Ag nanoparticles seem to be effective against the Gram-negative but not so much against the Gram-positive strains [6]. The antibacterial properties of a wide range of nanoparticles and their corresponding nanocomposites, such as ZnO [17][18], TiO2 [19][20], Fe3O4 [21][22

Thermophoretic tweezers for single nanoparticle manipulation

• Jošt Stergar and
• Natan Osterman

Beilstein J. Nanotechnol. 2020, 11, 1126–1133, doi:10.3762/bjnano.11.97

• implemented using a custom-built fluorescence microscope. By using an LED-optimized filter cube (Dapi/FITC/Cy3/Cy5 Quad LED HC Filter Set, AHF analysentechnik AG), Köhler illumination is utilized for fluorescence imaging using an LED as its light source. Light is collected from the sample plane by a 63

Gram-scale synthesis of splat-shaped Ag–TiO₂ nanocomposites for enhanced antimicrobial properties

• Mohammad Jaber,
• Asim Mushtaq,
• Kebiao Zhang,
• Jindan Wu,
• Dandan Luo,
• Zihan Yi,
• M. Zubair Iqbal and
• Xiangdong Kong

Beilstein J. Nanotechnol. 2020, 11, 1119–1125, doi:10.3762/bjnano.11.96

• multidrug-resistant bacterial strains. In this regard, metal-oxide-based antibacterial nanomaterials have received potential research interest due to the efficient prevention of microorganism growth. In this study, splat-shaped Ag–TiO2 nanocomposites (NCs) were synthesized on the gram scale and the enhanced

• antibacterial properties of TiO2 in the presence of silver were examined. The formation of Ag–TiO2 NCs was analyzed through various characterization techniques. The cell viability experimental results demonstrated that the Ag–TiO2 NCs have good biocompatibility. The antibacterial activity of the prepared Ag

• –TiO2 NCs was tested against the Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli) bacterial strains. The Ag–TiO2 NCs exhibited promising and superior antibacterial properties compared to TiO2 nanospheres as confirmed by the bacterial growth and inhibition zone

Monolayers of MoS₂ on Ag(111) as decoupling layers for organic molecules: resolution of electronic and vibronic states of TCNQ

• Asieh Yousofnejad,
• Gaël Reecht,
• Nils Krane,
• Christian Lotze and
• Katharina J. Franke

Beilstein J. Nanotechnol. 2020, 11, 1062–1071, doi:10.3762/bjnano.11.91

• vibronic states of an almost isolated molecule. Here, we use scanning tunneling microscopy and spectroscopy to show that a single layer of MoS2 on Ag(111) exhibits a semiconducting bandgap, which may prevent molecular states from strong interactions with the metal substrate. We show that the lowest

• explore this potential for MoS2 on a Ag(111) surface. In agreement with the band modifications of WS2 on Au(111) and Ag(111), we find that the bandgap remains almost the same, albeit shifted to lower energies [33]. As a test molecule we chose tetracyanoquinodimethane (TCNQ). Due to its electron-accepting

• vibronic states of the gas-phase molecule. Results and Discussion We have grown monolayer islands of MoS2 on an atomically clean Ag(111) surface, which had been exposed to sputtering–annealing cycles under ultrahigh vacuum before. The growth procedure was adapted from that of MoS2 on Au(111) [34][35], with

Electrochemical nanostructuring of (111) oriented GaAs crystals: from porous structures to nanowires

• Elena I. Monaico,
• Eduard V. Monaico,
• Veaceslav V. Ursaki,
• Shashank Honnali,
• Vitalie Postolache,
• Karin Leistner,
• Kornelius Nielsch and
• Ion M. Tiginyanu

Beilstein J. Nanotechnol. 2020, 11, 966–975, doi:10.3762/bjnano.11.81

• in a Teflon cell with the 0.2 cm2 area exposed to the electrolyte. The electrolytes used in this study were 1.75 M NaCl and 1 M HNO3. The experiments were performed in a three-electrode configuration, with a Pt mesh with a surface area of 6 cm2 acting as counter electrode, a saturated Ag/AgCl

Atomic layer deposition for efficient oxygen evolution reaction at Pt/Ir catalyst layers

• Stefanie Schlicht,
• Korcan Percin,
• Stefanie Kriescher,
• André Hofer,
• Claudia Weidlich,
• Matthias Wessling and
• Julien Bachmann

Beilstein J. Nanotechnol. 2020, 11, 952–959, doi:10.3762/bjnano.11.79

• Meinsberg) mounted in a Haber–Luggin capillary or a Ag/AgCl reference electrode was used. A platinum (coated titanium mesh) electrode was used as the counter electrode (Magneto Special Anodes B.V., The Netherlands). The working electrodes consist of the prepared catalyst-coated titanium electrodes

Measurement of electrostatic tip–sample interactions by time-domain Kelvin probe force microscopy

• Christian Ritz,
• Tino Wagner and
• Andreas Stemmer

Beilstein J. Nanotechnol. 2020, 11, 911–921, doi:10.3762/bjnano.11.76

• Christian Ritz Tino Wagner Andreas Stemmer Nanotechnology Group, ETH Zürich, Säumerstrasse 4, 8803 Rüschlikon, Switzerland present address: Zurich Instruments AG, Technoparkstrasse 1, 8005 Zürich, Switzerland 10.3762/bjnano.11.76 Abstract Kelvin probe force microscopy is a scanning probe

A Josephson junction based on a highly disordered superconductor/low-resistivity normal metal bilayer

• Pavel M. Marychev and
• Denis Yu. Vodolazov

Beilstein J. Nanotechnol. 2020, 11, 858–865, doi:10.3762/bjnano.11.71

• NbN/Al, NbN/Ag and MoN/Ag bilayers. Namely, the suppression of the critical temperature of the SN bilayer is smaller while the change in magnetic field penetration depth of the SN bilayer is larger than the Usadel model predicts. Therefore, the present results should be considered only as a route for

Adsorption behavior of tin phthalocyanine onto the (110) face of rutile TiO₂

• Lukasz Bodek,
• Mads Engelund,
• Aleksandra Cebrat and
• Bartosz Such

Beilstein J. Nanotechnol. 2020, 11, 821–828, doi:10.3762/bjnano.11.67

• protrudes from the macrocycle making the molecule nonplanar [20]. This enables the molecule to adsorb onto a surface with a tin atom pointing either towards the surface (Sn-down) or towards the vacuum (Sn-up). Similar findings were reported for the Ag(111) surface [21][22], where Sn-up Pc molecules appeared

• (above 5 V) leads to a lateral movement of the molecules or to their distortion. The conformational switching of SnPc molecules was previously discussed for the Ag(111) surface [21], the InAs(111) surface [26] and a 1 ML PTCDA/Ag(111) interface [27]. Using a C60-functionalized tip, successful switching

• between Sn-up and Sn-down was also reported on Cu(111) and Ag(100), while this reaction did not occur on Au(111) and Au(110) surfaces [28]. On the Ag(111) surface, within the first layer, Sn-up molecules were irreversibly switched to the down position, while on InAs(111), the molecules could be switched

A set of empirical equations describing the observed colours of metal–anodic aluminium oxide–Al nanostructures

• Cristina V. Manzano,
• Jakob J. Schwiedrzik,
• Gerhard Bürki,
• Laszlo Pethö,
• Johann Michler and
• Laetitia Philippe

Beilstein J. Nanotechnol. 2020, 11, 798–806, doi:10.3762/bjnano.11.64

• changed by changing the used metal (Pt/Pd, Al, Cr, Ag, or Au) [9][10], by using carbon [5], or by changing the thickness of the metal film [9][11][12]. There are two published studies in which wavelength values were generated by using a model that could predict colours by taking into account the

Nickel nanoparticles supported on a covalent triazine framework as electrocatalyst for oxygen evolution reaction and oxygen reduction reactions

• Secil Öztürk,
• Yu-Xuan Xiao,
• Dennis Dietrich,
• Beatriz Giesen,
• Juri Barthel,
• Jie Ying,
• Xiao-Yu Yang and
• Christoph Janiak

Beilstein J. Nanotechnol. 2020, 11, 770–781, doi:10.3762/bjnano.11.62

• material Ni(OH)2/graphene oxide has an onset potential of −0.17 V vs Ag/AgCl for ORR, which is 80 to 100 mV more positive than the corresponding onset potentials of unsupported Ni(OH)2 (−0.25 V vs Ag/AgCl) and exfoliated graphite oxide sheets (−0.27 V vs Ag/AgCl) [64]. In another study, Ni-N/C (nickel

• Autolab working station from Metrohm, Switzerland. Typically, a Ag/AgCl electrode (with saturated KCl solution) was used as a reference electrode, a carbon rod was used as a counter electrode, and a glassy-carbon rotating disk electrode (RDE, diameter: 5 mm, area: 0.196 cm2) was used as the working

Effect of Ag loading position on the photocatalytic performance of TiO₂ nanocolumn arrays

• Jinghan Xu,
• Yanqi Liu and
• Yan Zhao

Beilstein J. Nanotechnol. 2020, 11, 717–728, doi:10.3762/bjnano.11.59

• solar energy harvesting in photovoltaic and photocatalytic applications owing to their extremely high visible-light absorption and tuned effective band gap. In this work, Ag-loaded TiO2 nanocolumn (Ag-TNC) arrays were fabricated based on anodic aluminum oxide (AAO) template by combining atomic layer

• deposition (ALD) and vacuum evaporation. The effects of the Ag loading position and deposition thickness, and the morphology, structure and composition of Ag-deposited TNC arrays on its optical and photocatalytic properties were studied. The Ag-filled TiO2 (AFT) nanocolumn arrays exhibited higher removal

• efficiency of methylene blue (MB) compared with Ag-coated TiO2 (ACT) nanocolumn arrays and pure TiO2 nanocolumns arrays. Both experimental and theoretical simulation results demonstrated that the enhanced photocatalytic performance of AFT nanocolumn arrays was attributed to the surface plasmon resonance (SPR