TiO_x/Pt₃Ti(111) surface-directed formation of electronically responsive supramolecular assemblies of tungsten oxide clusters

• Marco Moors,
• Yun An,
• Agnieszka Kuc and
• Kirill Yu. Monakhov

Beilstein J. Nanotechnol. 2021, 12, 203–212, doi:10.3762/bjnano.12.16

• combination of these two species forms the characteristic stripe pattern of the z’-TiOx phase. Inside the trenches between the stripes, several holes in the film can be found, which are probably caused by the stress release during the film growth. These defects permit a direct contact with the underlying

• substrate and, thus, they should be special attraction points for adsorbates. As shown in Figure 1c and Figure 1d, it is very probable that W3O9 clusters prefer to adsorb these defects inside the trenches of the z’-TiOx phase. The result is a 1D alignment of the clusters along the direction of the stripes

• interaction with the substrate. The exclusive positioning of the W3O9 clusters on the point defects inside the trenches leads us to the conclusion that the preferred interaction with the metallic substrate below the oxide film compensates any charge injection or removal induced by the STM tip. For that

ZnO and MXenes as electrode materials for supercapacitor devices

• Ameen Uddin Ammar,
• Ipek Deniz Yildirim,
• Feray Bakan and
• Emre Erdem

Beilstein J. Nanotechnol. 2021, 12, 49–57, doi:10.3762/bjnano.12.4

• materials provide a fundamental understanding regarding the manner in which 2D structures are impacted by defects compared to bulk. Such an approach would therefore serve the scientific community with the material design tools needed to fabricate the next generation of supercapacitor devices. Keywords: 2D

• 2D structures are impacted by defects compared to the bulk. Such an approach would therefore serve the scientific community with the materials design tools needed to fabricate the next generation of supercapacitor devices. It must be borne in mind that the way in which carrier transport is enhanced

• in semiconductors is fundamentally the same, regardless of composition. Defects generate bandgap states that either generate electrons in the conduction band or holes in the valence band. Therefore, we believe that the discussion, based on experimental results, of the magnitude of this effect for 2D

Atomic layer deposited films of Al₂O₃ on fluorine-doped tin oxide electrodes: stability and barrier properties

• Hana Krýsová,
• Michael Neumann-Spallart,
• Hana Tarábková,
• Pavel Janda,
• Ladislav Kavan and
• Josef Krýsa

Beilstein J. Nanotechnol. 2021, 12, 24–34, doi:10.3762/bjnano.12.2

• , or to the perovskite (depending on the device type). This parasitic effect occurs through defects, such as pinholes and cracks in the blocking layer. Their presence is identified by the occurrence of anodic currents assigned to the oxidation of [Fe(CN)6]4− at FTO areas exposed by these defect sites

• that of pure FTO is higher than three. This means that there are B-type defects in the barrier film. These defects cause not only the delamination of the Al2O3 film from the FTO substrate, but also a slowdown of the charge-transfer kinetics (accompanied by a strong increase in ΔEpp). The Table 1 shows

Bio-imaging with the helium-ion microscope: A review

• Matthias Schmidt,
• James M. Byrne and
• Ilari J. Maasilta

Beilstein J. Nanotechnol. 2021, 12, 1–23, doi:10.3762/bjnano.12.1

Towards 3D self-assembled rolled multiwall carbon nanotube structures by spontaneous peel off

• Jonathan Quinson

Beilstein J. Nanotechnol. 2020, 11, 1865–1872, doi:10.3762/bjnano.11.168

• /N2/C3 structure is shown in Figure 2. The D peak refers to a defect in the MWCNT structure. An intense D peak (relative to the G peak intensity) correlates to higher defects, for instance, induced by nitrogen doping. The G and 2D peaks are related to the graphitization of MWCNTs. An intense G peak

Nanocasting synthesis of BiFeO₃ nanoparticles with enhanced visible-light photocatalytic activity

• Thomas Cadenbach,
• Maria J. Benitez,
• A. Lucia Morales,
• Cesar Costa Vera,
• Luis Lascano,
• Francisco Quiroz,
• Alexis Debut and
• Karla Vizuete

Beilstein J. Nanotechnol. 2020, 11, 1822–1833, doi:10.3762/bjnano.11.164

• catalytic performance in terms of overall degradation efficiency of the 5.5 nm particles is significantly superior compared to those of similarly sized particles reported. It also much improved when compared with samples free of surface defects synthesized by a previously reported co-precipitation method

• lead to a decrease in photocatalytic activity due to crystal defects and local distortions altering the skin layer of the BiFeO3 photocatalysts [28][53][56]. From this results we conclude that the nanocasting method for the synthesis of BiFeO3 does not only produce pure-phase, uniform BiFeO3 with a

• very narrow particle size distribution. The results also suggest that the nanoparticles are characterized by a low concentration of surface defects and a low level of local strain, which is ideal for surface-based applications such as photocatalysis. This is confirmed by the reaction kinetics of the

Molecular dynamics modeling of the influence forming process parameters on the structure and morphology of a superconducting spin valve

• Alexander Vakhrushev,
• Aleksey Fedotov,
• Vladimir Boian,
• Roman Morari and
• Anatolie Sidorenko

Beilstein J. Nanotechnol. 2020, 11, 1776–1788, doi:10.3762/bjnano.11.160

• cobalt with an increase in the substrate temperature will decrease the transparency parameter TF and worsen the functional parameters of the layered S/F heterostructure. The implementation of optimal technological processes is required to minimize these defects and imperfections of layered nanosystems

Mapping of integrated PIN diodes with a 3D architecture by scanning microwave impedance microscopy and dynamic spectroscopy

• Rosine Coq Germanicus,
• Peter De Wolf,
• Florent Lallemand,
• Catherine Bunel,
• Serge Bardy,
• Hugues Murray and
• Ulrike Lüders

Beilstein J. Nanotechnol. 2020, 11, 1764–1775, doi:10.3762/bjnano.11.159

• the measurements of the electrical interactions of a biased tip–sample nanoscale system [1][2]. Scanning spreading resistance microscopy (SSRM) and scanning capacitance microscopy (SCM) [3][4][5] are modes widely used for the detection of charge carriers, carrier types, and density of defects. These

Out-of-plane surface patterning by subsurface processing of polymer substrates with focused ion beams

• Serguei Chiriaev,
• Luciana Tavares,
• Vadzim Adashkevich,
• Arkadiusz J. Goszczak and
• Horst-Günter Rubahn

Beilstein J. Nanotechnol. 2020, 11, 1693–1703, doi:10.3762/bjnano.11.151

• wrinkle-like micropatterns [23][24]. In this work, we have employed thin films of a Pt60Pd40 alloy and of pristine Au. The primary reason for this choice was the difference in their microstructures, specifically in the availability of structural defects capable of providing the release of gases from

• (Figure S1a and Figure S1b, Supporting Information File 1), meaning that this fraction is wasted with regard to defect generation inside the PMMA layer. In contrast, Ne+ and Ga+ ions lose their energy entirely in the PMMA layer; therefore, the total ion energy is utilized for generating the defects in

The influence of an interfacial hBN layer on the fluorescence of an organic molecule

• Christine Brülke,
• Oliver Bauer and
• Moritz M. Sokolowski

Beilstein J. Nanotechnol. 2020, 11, 1663–1684, doi:10.3762/bjnano.11.149

• the optical excitation can occur. The different FL lines can be ascribed to different environments of the adsorption sites, namely molecules adsorbed at surface defects, in large ordered domains, and located in the second layer. Keywords: decoupling; fluorescence; hexagonal boron nitride; 3,4,9,10

• spectrum). An enhancement of radiative interband transitions has been reported for Cu nanoparticles [40]. We thus speculate that surface defects (protrusions) play a role here. This is in agreement with our observation that the intensity of this “defect luminescence” in region I depends on the exact

• additional enhancement [46]. According to the electromagnetic mechanism, on a rough surface, surface plasmon polaritons (SPPs) can also be excited by the incident light. The surface plasmons are located in the vicinity of surface defects, such as protrusions. The field enhancement at these defects leads to

PTCDA adsorption on CaF₂ thin films

• Philipp Rahe

Beilstein J. Nanotechnol. 2020, 11, 1615–1622, doi:10.3762/bjnano.11.144

• (111) surface with deposition on thicker CaF2/CaF1/Si(111) films. The identification of mostly single molecules on the CaF1/Si(111) interface layer is explained by the presence of atomic-size defects within this layer. Geometry-optimisation calculations using density functional theory reveal a geometry

• ) reconstruction. After PTCDA deposition, individual double-lobe features are apparent in STM at negative sample bias on the CaF1/Si(111) areas (see also Figure 1b), in addition to the dark spots that were identified before as single atomic-size defects within the CaF1 interface layer [27]. Each of these double

• , coupling to defects within the CaF1 layer, or charge transfer into the LUMO. Imaging at a positive sample bias of +1.5 V was performed in constant-height mode as the reduced sample conductivity at positive bias impeded operation in constant-current mode. Still, conductivity through PTCDA molecules is also

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

• deposited on the surface. The parameters and duration of the PEO process should be carefully determined, as intensive energy input and longer treatment duration may create excessive surface roughness or even introduce unexpected defects on the surface. Thus, a set of moderate parameters was applied in this

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

• , it is also an anti-ferromagnet due to electron correlation effects and it shows catalytic activity [14][15][16][17]. As a thin film grown on Ir(100), the oxide is of extremely high quality [18][19][20] avoiding the complexity that arises from atomic-scale defects in bulk materials [5][6][7][8]. The

• diffusive motion of the molecules since the directional intermolecular bond always “swings open”. Increasing the annealing temperature does not help to form supramolecular structures at low coverage. At 300 K, all molecules will attach to defects or move to 1BL CoO areas present in the film. In contrast, 2

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

• surface has to be determined: However, this equation is only valid for equilibrium states on ideal surfaces. Defects on the substrate can lead to hysteresis effects that change the contact wetting angle [38]. Other surface effects, such as coarsening, ageing, or ripening can additionally lead to

Atomic defect classification of the H–Si(100) surface through multi-mode scanning probe microscopy

• Jeremiah Croshaw,
• Thomas Dienel,
• Taleana Huff and
• Robert Wolkow

Beilstein J. Nanotechnol. 2020, 11, 1346–1360, doi:10.3762/bjnano.11.119

• available via a single imaging mode. We demonstrate this through the characterization and classification of several commonly found defects of the hydrogen-terminated silicon (100)-2 × 1 surface (H–Si(100)-2 × 1) by using six unique imaging modes. The H–Si surface was chosen as it provides a promising

• platform for the development of atom scale devices, with recent work showing their creation through precise desorption or placement of surface hydrogen atoms. While samples with relatively large areas of the H–Si surface are routinely created using an in situ methodology, surface defects are inevitably

• formed reducing the area available for patterning. By probing the surface using the different interactivity afforded by either hydrogen- or silicon-terminated tips, we are able to extract new insights regarding the atomic and electronic structure of these defects. This allows for the confirmation of

Effect of localized helium ion irradiation on the performance of synthetic monolayer MoS₂ field-effect transistors

• Jakub Jadwiszczak,
• Pierce Maguire,
• Conor P. Cullen,
• Georg S. Duesberg and
• Hongzhou Zhang

Beilstein J. Nanotechnol. 2020, 11, 1329–1335, doi:10.3762/bjnano.11.117

• of well-performing monolayer TMD films [3][4][5], leading to viable large-scale integration of on-chip TMD FETs. With device miniaturization, it becomes key to understand the impact of defects such as chalcogen vacancies on the electrical transport properties of FETs based on 2D semiconductors. This

• is particularly crucial for device applications in radiation-rich environments (e.g., space satellite technologies), since defects can be introduced by ionizing particle irradiation while the devices are in continuous operation. Recently, noble gas ion beam irradiation has opened the field to the

• exploration of nanometer-scale structural modifications of TMD devices [6][7][8]. The localized formation of defects by focused ion beam irradiation has been shown to induce unusual electronic properties in monolayer TMDs, such as pseudo-metallic phase transitions in MoS2 and WSe2 [9][10], resistive switching

An atomic force microscope integrated with a helium ion microscope for correlative nanoscale characterization

• Santiago H. Andany,
• Gregor Hlawacek,
• Stefan Hummel,
• Charlène Brillard,
• Mustafa Kangül and
• Georg E. Fantner

Beilstein J. Nanotechnol. 2020, 11, 1272–1279, doi:10.3762/bjnano.11.111

• fabrication capabilities of the HIM [33] and studying these local defects created at the micro- and nanoscale can provide valuable information towards understanding these limitations. For example, a focused helium ion beam can locally destroy the crystalline structure of silicon and lead to the growth of

• characterized the defects caused by He ion exposure in a correlative AFM–HIM experiment. Amorphous silicon bubbles are created on a crystalline silicon substrate through point exposition with the HIM at 25 kV and 14 pA using doses between 4.2 × 108 and 4.2 × 109 He ions (Figure 3). He ions penetrate deep into

Gas sorption porosimetry for the evaluation of hard carbons as anodes for Li- and Na-ion batteries

• Yuko Matsukawa,
• Fabian Linsenmann,
• Maximilian A. Plass,
• George Hasegawa,
• Katsuro Hayashi and
• Tim-Patrick Fellinger

Beilstein J. Nanotechnol. 2020, 11, 1217–1229, doi:10.3762/bjnano.11.106

• negative electrode [9]. We herein refer to HCs as strongly disordered carbons (having a high fraction of sp3-hybridized defects or heteroatoms), independent of their graphitizability. After the introduction of the LIB, efforts in research and development on sodium-ion anodes, i.e., lithium-analogue

• electrolyte. It was further shown that additional irreversible capacity can arise from alkali metal ions reacting with surface defects or reactive surface groups and small molecules other than the electrolyte adsorbed to the walls of nanometric pores that were not removed during the cell production [17

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

• nearly perpendicular to the aromatic backbone and two smaller double lobes which correspond to the bisbenz[5,6]indeno end groups [26]. The large-area LT-STM measurement shown in Supporting Information File 1, Figure S2 reveals highly ordered molecular domains with defects at the domain boundaries as well

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

• regarding the sensitivity and the diffraction-limited optical resolution. Thus, a high-resolution technique that reveals both, the structural and the optical properties at the nanometer scale is needed to study the fraction of crystalline phases and defects within the SiNWs. Tip-enhanced Raman spectroscopy

• SiNWs are mainly single crystalline. However, in some areas along the nanowire axis defects are present as well (Figure 1a). The diffraction pattern of this part of the SiNW (Figure 1b) shows more than one reflection, which indicates that the structure of the SiNW consists presumably of segments or

• ]. For polarization angle-resolved emission measurements, a Glan–Taylor prism as polarization filter is positioned in front of the entrance slit of the spectrometer. a) High-resolution TEM image of a segment of a SiNW obtained through Pt-catalyzed growth that exhibits several defects and differently

A few-layer graphene/chlorin e6 hybrid nanomaterial and its application in photodynamic therapy against Candida albicans

• Selene Acosta,
• Carlos Moreno-Aguilar,
• Dania Hernández-Sánchez,
• Beatriz Morales-Cruzado,
• Erick Sarmiento-Gomez,
• Carla Bittencourt,
• Luis Octavio Sánchez-Vargas and
• Mildred Quintana

Beilstein J. Nanotechnol. 2020, 11, 1054–1061, doi:10.3762/bjnano.11.90

• occurs in graphite. The intensity of the 2D band is reduced in the FLG-Ce6 hybrid nanomaterial due to the interaction between FLG and Ce6 π-electrons. Finally, the D band (≈1350 cm−1) is not present in the Raman spectrum of pristine graphite as it gives information about the in-plane defects of 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

• nanometers [18][19][20][21][22]. Also, defects in GNRs have been one way of engineering the absorption spectrum of detectors based on these materials. We have shown that defects in GNR transistors can improve the device performance [23], but the limitation of GNRs to carrying the current and the fabrication

• , these devices are tunable by varying the neck width. A4Z6-6 exhibits a large current in comparison with A4Z6-24. This is attributed to an increase in the amount of defects in A4Z6-24, i.e., the increasing scattering of carriers decreases the transmission. Another reason is the size of the bandgap

• is 1000-fold that of graphene detectors and 100-fold that of GNR devices. In addition, GNMs are tunable materials, meaning that by tuning the diameter and distribution of the defects, their optical and electrical properties can be engineered. Graphene nanomesh structures. (a) A4Z6-6, (b) A4A4-6, and

Band tail state related photoluminescence and photoresponse of ZnMgO solid solution nanostructured films

• Vadim Morari,
• Aida Pantazi,
• Nicolai Curmei,
• Vitalie Postolache,
• Emil V. Rusu,
• Marius Enachescu,
• Ion M. Tiginyanu and
• Veaceslav V. Ursaki

Beilstein J. Nanotechnol. 2020, 11, 899–910, doi:10.3762/bjnano.11.75

• discussed above, we suppose that the difference in the electrical parameters of films prepared by the two methods is determined by the specific features of the technology. The concentration of unintentionally introduced impurities and intrinsic defects is different with the two methods, particularly due to

• by spray pyrolysis are due to inhomogeneous distribution of intrinsic defects or unintentional doping impurities, as previously observed in undoped [38][49] or Cu, Ni, Co, or Al doped [46][50] ZnO materials, instead of local composition fluctuations. Usually, the full width at half maximum (FWHM) of

• films prepared by spin coating reaches values of 200 meV, while the material is highly resistive, as mentioned above. This means that the formation of large band tails in films prepared by spin coating cannot be attributed to doping with impurities or to intrinsic defects, but to local composition

Three-dimensional solvation structure of ethanol on carbonate minerals

• Hagen Söngen,
• Ygor Morais Jaques,
• Peter Spijker,
• Christoph Marutschke,
• Stefanie Klassen,
• Ilka Hermes,
• Ralf Bechstein,
• Lidija Zivanovic,
• John Tracey,
• Adam S. Foster and
• Angelika Kühnle

Beilstein J. Nanotechnol. 2020, 11, 891–898, doi:10.3762/bjnano.11.74

• density. This model has worked well in previous works with the solvent water [10], even in the case of defects [21]. There is excellent qualitative agreement between the experimentally obtained frequency shift data (Figure 1) and the atomic density data from the MD simulations (Figure 2). The AFM data

Simulations of the 2D self-assembly of tripod-shaped building blocks

• Łukasz Baran,
• Wojciech Rżysko and
• Edyta Słyk

Beilstein J. Nanotechnol. 2020, 11, 884–890, doi:10.3762/bjnano.11.73

• networks, we observe small defects, which are artifacts of the cooling process. These can also be observed very often in experiments. For model WT111 (Figure 2c) the formation of a different structure occurs. Also, there is only one aggregate built of almost all molecules in the system. It is surprising