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

• networks [38], wires of polycyclic aromatic hydrocarbons [39], and graphene patches [40][41] were also performed on hBN/Cu(111). However, advanced supramolecular architectures, such as organic porous networks, have not been reported on either hBN/Cu(111) or other metal-supported hBN monolayers so far, in

• anchor for noncovalent functionalization, e.g., to develop graphene platforms to be used in sensing applications [65][66][67] and to employ hBN monolayers for capturing aromatic organic pollutants [68]. On bulk insulators, it was, for instance, demonstrated how the optical properties of an adsorbed

• revealed weak molecule–support interactions. The STM data showed an electronic patterning of the pyrene films with periodicities in the single digit nanometer range. Furthermore, we provide a first case study for the self-assembly of advanced porous structures on hBN monolayers, introducing a chiral kagome

Analysis of catalyst surface wetting: the early stage of epitaxial germanium nanowire growth

• Owen C. Ernst,
• Felix Lange,
• David Uebel,
• Thomas Teubner and
• Torsten Boeck

Beilstein J. Nanotechnol. 2020, 11, 1371–1380, doi:10.3762/bjnano.11.121

• has a thickness 0.32 nm, one or two gold monolayers are stable on silicon, as long as the systems are in thermodynamic equilibrium. Experimental results Gold on silicon oxide UHV−PVD-deposited gold droplets on SiOx are characterized in Figure 2a. The dependence of gold droplet mean diameter and the

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

• or PFP with a flat-lying (long and short molecular axes parallel to the substrate) orientation, which have IEs (in monolayers on graphite) of 5.65 eV and 6.20 eV, respectively [25][26]. The decrease in the IE is due to solid state polarization, which is a general phenomenon for molecular thin films

• contribution polarization [11][44]. Perfluorination does not impact the orientation of PEN and PFP in the contact layer with clean metals, where both compounds are lying flat [9][30][31][47][48][49][50][51][52]. On Au(111), the coupling strength of both monolayers with the substrate is rather similar and

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

• Robby Reynaerts Kunal S. Mali Steven De Feyter Department of Chemistry, Division of Molecular Imaging and Photonics, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium 10.3762/bjnano.11.113 Abstract Structural polymorphism is ubiquitous in physisorbed self-assembled monolayers formed at the

• than one type of packing – a property widely known as crystal polymorphism – is not limited to the realm of bulk (3D) crystals but also extends to the 2D world of physisorbed self-assembled monolayers [1][2][3][4]. In fact, observation of multiple polymorphic networks, especially for organic monolayers

• 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

Role of redox-active axial ligands of metal porphyrins adsorbed at solid–liquid interfaces in a liquid-STM setup

• Thomas Habets,
• Sylvia Speller and
• Johannes A. A. W. Elemans

Beilstein J. Nanotechnol. 2020, 11, 1264–1271, doi:10.3762/bjnano.11.110

• no direct metal atom coordination from the substrate is possible. To our surprise we found a strong influence of the solvent on the success of imaging the molecules with STM. When n-tetradecane was used as the solvent, monolayers of MnTUPCl readily formed on Au(111) (Figure 1c), while poorly

• in measured tunneling current. While the imaging of monolayers of MnTUPCl and other metal porphyrins based on the TUP-ligand generally requires a tunneling set current of less than 5 pA [7][10][11][12][13], now additional currents of several tens of picoamperes were present. Remarkably, the

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

• 12–24 hours. The experiments were performed to create self-assembled monolayers (SAMs) of cysteamine cross-linked with ᴅʟ-glyceraldehyde on the microcantilever surface to selectively capture the targeted Cd(II). The proposed portable microfluidic platform is able to achieve the detection in 20–23 min

• the WHO limit of 3 μg/L. Keywords: BioMEMS; heavy metal ions (HMIs); limit of detection (LOD); microcantilevers; microfluidics; micro-electromechanical systems (MEMS); piezoresistive sensors; SAM (self-assembled monolayers); World Health Organization (WHO); Introduction Water is fundamentally

Nonadiabatic superconductivity in a Li-intercalated hexagonal boron nitride bilayer

• Kamila A. Szewczyk,
• Izabela A. Domagalska,
• Artur P. Durajski and
• Radosław Szczęśniak

Beilstein J. Nanotechnol. 2020, 11, 1178–1189, doi:10.3762/bjnano.11.102

• form of hBN was obtained at the University of Manchester [32]. Monolayers of graphene and hBN have a very similar crystal lattice structure. Their compatibility is estimated to be 98.5% [23]. In a graphene/hBN composite, a homogeneous distribution of charge on the graphene surface is observed. This

• result is radically different from the data obtained for graphene/SiO2 [33]. In addition, hBN monolayers exhibit a high temperature stability, a low dielectric constant (ε = 3–4), and a high thermal conductivity [34]. The band gap of hBN is about 5.9 eV [35]. Furthermore, which is also important, hBN is

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

• cohesive energy that overcompensates through intermolecular hybridization the energy cost for planarization [13][31]. Flat C42H28 molecules were previously reported for monolayers on Au(111) [32], while on Bi(001) a coexistence of twisted and planar C42H28 was observed [33]. The unit cell of the

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

• nanomaterial used, for example, aqueous solutions, self-assembled monolayers or polymeric nanocomposites [33]. In the case of plasmonic nanoparticles, the plasmonic properties (i.e., the maximum position of the absorption band and the band shape) are strongly affected by the conditions under which the

• monolayers consisting of a weak electrolytic (i.e., pH-sensitive), 11-mercaptoundecanoic acid, a strong electrolytic (i.e., pH-independent), and (10-mercaptodecyl)trimethylammonium bromide. In addition, the resulting photothermal effect did not cause damage to the surrounding healthy tissue. Multibranched

• excitation by near-infrared light at 808 nm causes localized heating (up to 81 °C) that is capable of destroying the bacteria nearby [61]. Gold nanostar monolayers with a tunable LSPR absorption were grafted onto glass slides and were found to efficiently eliminate an S. aureus biofilm upon NIR laser

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

• and K′ by circularly polarized light [32]. The potential as decoupling layer for molecules may become even more appealing by the fact that monolayers of transition metal dichalcogenides can be grown in situ on different metal surfaces, where the precise hybridization and band alignment depend on the

A new photodetector structure based on graphene nanomeshes: an ab initio study

• Babak Sakkaki,
• Hassan Rasooli Saghai,
• Ghafar Darvish and
• Mehdi Khatir

Beilstein J. Nanotechnol. 2020, 11, 1036–1044, doi:10.3762/bjnano.11.88

• makes it suitable for optical devices. Keywords: absorption spectra; DFT calculations; graphene nanomesh; graphene nanoribbon; photodetectors; Introduction Graphene monolayers with honeycomb crystal structure have unique electrical and optical properties and have received a lot of attention recently

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

• temperature. The difference in the adsorption process between (110) and (011) surfaces is clear when increasingly more molecules are evaporated onto the surface. After deposition of the equivalent of a few monolayers, the formation of well-ordered phases of non-flat lying molecules is observed on the rutile

Light–matter interactions in two-dimensional layered WSe₂ for gauging evolution of phonon dynamics

• Avra S. Bandyopadhyay,
• Chandan Biswas and
• Anupama B. Kaul

Beilstein J. Nanotechnol. 2020, 11, 782–797, doi:10.3762/bjnano.11.63

• the damping mechanisms in WSe2 with varying thickness and the increase in energy from external stimuli. The insights from this work reveal the importance of light–matter interactions in 2D WSe2 to alter the phonon spectrum toward the quantum-confined limit of monolayers. These findings can be broadly

Hexagonal boron nitride: a review of the emerging material platform for single-photon sources and the spin–photon interface

• Stefania Castelletto,
• Faraz A. Inam,
• Shin-ichiro Sato and
• Alberto Boretti

Beilstein J. Nanotechnol. 2020, 11, 740–769, doi:10.3762/bjnano.11.61

• ]. This has prompted the investigation of SP confocal microscopy to observe SPEs from various h-BN types of materials from bulk to monolayers, however with similar unclear attributions. Despite the PL variability in h-BN, very recently, deep-level, atom-like luminescent defects in h-BN have been

• miscellaneous transition rates for the optical and non-radiative transitions of the emitters. The SPEs show a very good photo-stability under ambient conditions and in monolayers. A correlation between the defect orientation and the h-BN hexagonal structure is observed by studying the excitation polarization

• 442 nm to 780 nm with operation from cryogenic to very high temperatures (1100 K). DFT was used to understand the origin of such broadband emission possible from defect states related to H, O, C, N, and B induced defects in bulk and monolayers indicating the emission-related defects population

Quantitative determination of the interaction potential between two surfaces using frequency-modulated atomic force microscopy

• Nicholas Chan,
• Carrie Lin,
• Tevis Jacobs,
• Robert W. Carpick and
• Philip Egberts

Beilstein J. Nanotechnol. 2020, 11, 729–739, doi:10.3762/bjnano.11.60

• such issues. For example, the adsorption of self-assembled monolayers on contacting surfaces is one method by which the surface can be modified to reduce the detrimental impacts of adhesion, friction and wear [15][16][17]. The nanometer length scales over which these processes modify surface

Luminescent gold nanoclusters for bioimaging applications

• Nonappa

Beilstein J. Nanotechnol. 2020, 11, 533–546, doi:10.3762/bjnano.11.42

• , semiconductor quantum dots suffer from toxicity and are susceptible to oxidation. In this context, atomically precise gold nanoclusters protected by thiol monolayers have emerged as a new class of luminescent nanomaterials. Low toxicity, bioavailability, photostability as well as tunable size, composition, and

Multilayer capsules made of weak polyelectrolytes: a review on the preparation, functionalization and applications in drug delivery

• Varsha Sharma and
• Anandhakumar Sundaramurthy

Beilstein J. Nanotechnol. 2020, 11, 508–532, doi:10.3762/bjnano.11.41

• between β-cyclodextrin monolayers as host and polymers modified with adamantyl groups as guests, which also resulted in stable multilayers [61]. The first stimuli-responsive supramolecular hydrogels films based on these reactions were built in 2006 using β-cyclodextrin and adamantyl modified chitosan

DFT calculations of the structure and stability of copper clusters on MoS₂

• Cara-Lena Nies and
• Michael Nolan

Beilstein J. Nanotechnol. 2020, 11, 391–406, doi:10.3762/bjnano.11.30

• structures and MoS2 monolayers is therefore of significant importance and first-principles simulations can probe aspects of this interaction not easily accessible to experiment. Previous theoretical studies have focused particularly on the adsorption of a range of metallic elements, including first-row

• character of Cu nanoclusters is preserved. Keywords: copper (Cu); density functional theory (DFT); 2D materials; molybdenum disulfide (MoS2); thin film nucleation; Introduction Since the successful exfoliation of monolayers of graphene by Novoselov et al., 2D materials have gained a large interest in a

• adsorption [26][29][30][31] and adsorption of larger structures such as nanoparticles [25] or metal chains [24]. Studies of single-atom adsorption have focused on screening the stability of a range of elements at TMD monolayers. As an example, Wang et al. [26] studied the adsorption energy, stable geometries

Brome mosaic virus-like particles as siRNA nanocarriers for biomedical purposes

• Alfredo Nuñez-Rivera,
• Pierrick G. J. Fournier,
• Danna L. Arellano,
• Ana G. Rodriguez-Hernandez,
• Rafael Vazquez-Duhalt and
• Ruben D. Cadena-Nava

Beilstein J. Nanotechnol. 2020, 11, 372–382, doi:10.3762/bjnano.11.28

• described previously. When the cell monolayers reached about 70% confluence, the medium was completely removed and cells were synchronized in basal media for 12 h. The cells were then further incubated in the presence of BMV or CCMV (20 µg/mL, 2.6 × 107 virions per cell) or DMSO (20% v/v) as a control for

Rational design of block copolymer self-assemblies in photodynamic therapy

• Maxime Demazeau,
• Laure Gibot,
• Anne-Françoise Mingotaud,
• Patricia Vicendo,
• Clément Roux and
• Barbara Lonetti

Beilstein J. Nanotechnol. 2020, 11, 180–212, doi:10.3762/bjnano.11.15

Internalization mechanisms of cell-penetrating peptides

• Ivana Ruseska and
• Andreas Zimmer

Beilstein J. Nanotechnol. 2020, 11, 101–123, doi:10.3762/bjnano.11.10

Antimony deposition onto Au(111) and insertion of Mg

• Lingxing Zan,
• Da Xing,
• Abdelaziz Ali Abd-El-Latif and
• Helmut Baltruschat

Beilstein J. Nanotechnol. 2019, 10, 2541–2552, doi:10.3762/bjnano.10.245

• processes are kinetically slow because of the large ionic radius and high charge density of Mg2+ compared with Li+. In this work, we prepared very thin films of Sb by electrodeposition on a Au(111) substrate. Monolayer and multilayer deposition (up to 20 monolayers) were characterized by cyclic voltammetry

• the potential cycle to more negative potentials, bulk Sb starts around 0.13 V and gives rise to the peak C3 and the corresponding dissolution peak A3. Peak C1 and peak A2 largely decrease after extensive bulk deposition of nearly two monolayers in the fourth cycle. We attribute the decrease of peak A2

• . The reversibility of the magnesium bulk deposition/dissolution is nearly 97%. From the Sb deposition charge (10.36 mC cm−2), the amount of the deposited Sb was calculated to be 20 monolayers, which is comparable to the STM results. The amount of the inserted Mg was 6.39 mC cm−2. The ratio between the

Mobility of charge carriers in self-assembled monolayers

• Zhihua Fu,
• Tatjana Ladnorg,
• Hartmut Gliemann,
• Alexander Welle,
• Asif Bashir,
• Michael Rohwerder,
• Qiang Zhang,
• Björn Schüpbach,
• Andreas Terfort and
• Christof Wöll

Beilstein J. Nanotechnol. 2019, 10, 2449–2458, doi:10.3762/bjnano.10.235

• study charge transport within 2D layers of organic semi-conductors (OSCs) using atomic force microscopy (AFM)-based lithography applied to self-assembled monolayers (SAMs), fabricated from appropriate organothiols. The extent of lateral charge transport was investigated by insulating pre-defined patches

• , using an approach where measurements are carried out for structurally well-defined self-assembled monolayers (SAMs) [9], fabricated from appropriate organothiols. A very large number of organothiolates have been found to form monolayers of high structural quality on Au substrates [10], with a pronounced

• before the SAM preparation. The formation of the PAT monolayers was carried out by immersing the substrates into 0.1 mM absolute ethanolic solution (≥99.8%, AnalaR NORMAPUR® ACS, Reag. Ph. Eur. zur Analyse) of PAT for 24 h at RT and, optionally, at an elevated temperature (70 °C). The samples were

Multiwalled carbon nanotube based aromatic volatile organic compound sensor: sensitivity enhancement through 1-hexadecanethiol functionalisation

• Nadra Bohli,
• Meryem Belkilani,
• Juan Casanova-Chafer,
• Eduard Llobet and
• Adnane Abdelghani

Beilstein J. Nanotechnol. 2019, 10, 2364–2373, doi:10.3762/bjnano.10.227

• sensitivity (up to 17 times), selectivity and improves the response dynamics of the sensors. Keywords: gold-decorated MWCNTs; multiwall carbon nanotubes (MWCNTs); self-assembled monolayers (SAMs); sensitivity; selectivity; vapour sensor; Introduction Aromatic volatile organic compounds (VOCs) such as

• effect of nucleation. The power and time required for the plasma beam aperture within the cell were optimized and fixed to 30 W and 10 seconds, respectively. Functionalisation with self-assembled monolayers (SAMs) The Au-decorated MWCNT substrate was further functionalized with an alkanethiol self

• performance [25][26]. FTIR characterisation In order to ensure that the HDT monolayers are formed and well immobilized on the Au-MWCNT layers, we used FTIR spectroscopy. Figure 3 shows the infrared spectra, in absorbance mode, of both Au-MWCNT and HDT/Au-MWCNT layers. When analysing and comparing the infrared

Adsorption and desorption of self-assembled L-cysteine monolayers on nanoporous gold monitored by in situ resistometry

• Elisabeth Hengge,
• Eva-Maria Steyskal,
• Rupert Bachler,
• Alexander Dennig,
• Bernd Nidetzky and
• Roland Würschum

Beilstein J. Nanotechnol. 2019, 10, 2275–2279, doi:10.3762/bjnano.10.219

• 12, A-8010 Graz, Austria 10.3762/bjnano.10.219 Abstract Surface modifications of nanoporous metals have become a highly attractive research field as they exhibit great potential for various applications, especially in biotechnology. Using self-assembled monolayers is one of the most promising

• approaches to modify a gold surface. However, only few techniques are capable of characterizing the formation of these monolayers on porous substrates. Here, we present a method to in situ monitor the adsorption and desorption of self-assembled monolayers on nanoporous gold by resistometry, using cysteine as

• resistometry. From the desorption peak related to the (111) surface of the structure, which is associated with a resistance change of 4.8%, an initial surface coverage of 0.48 monolayers of cysteine could be estimated. Keywords: L-cysteine; in situ resistometry; nanoporous gold; self-assembled monolayer (SAM