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

• observed for hBN on SiO2/Si [61], on Cu foils [62], and on other metal foils [63][64] for our samples of hBN/Cu(111). This is an obvious discrepancy, which we cannot explain based on our current data. It may, however, be related to the specific interface between hBN and the single crystalline Cu substrate

Selective detection of complex gas mixtures using point contacts: concept, method and tools

• Alexander P. Pospelov,
• Victor I. Belan,
• Dmytro O. Harbuz,
• Volodymyr L. Vakula,
• Lyudmila V. Kamarchuk,
• Yuliya V. Volkova and
• Gennadii V. Kamarchuk

Beilstein J. Nanotechnol. 2020, 11, 1631–1643, doi:10.3762/bjnano.11.146

• Spectroscopy of Molecular Systems and Nanostructured Materials, B. Verkin Institute for Low Temperature Physics and Engineering, 47 Nauky Ave., Kharkiv, 61103, Ukraine Department of Pediatrics and Rehabilitation, SI “Institute for Children and Adolescents Health Care” of NAMS of Ukraine, 52-A Yuvileinyi Ave

• ., Kharkiv, 61153, Ukraine Department of Pediatrics, V. Karazin Kharkiv National University, 4 Svobody Sq., Kharkiv, 61077, Ukraine Laboratory of Age Endocrinology and Metabolism, SI “Institute for Children and Adolescents Health Care” of NAMS of Ukraine, 52-A Yuvileinyi Ave., Kharkiv, 61153, Ukraine

A self-powered, flexible ultra-thin Si/ZnO nanowire photodetector as full-spectrum optical sensor and pyroelectric nanogenerator

• Liang Chen,
• Jianqi Dong,
• Miao He and
• Xingfu Wang

Beilstein J. Nanotechnol. 2020, 11, 1623–1630, doi:10.3762/bjnano.11.145

• work, a new type of self-powered, high-performance ultra-thin p-Si/n-ZnO nanowire (NW) flexible photodetector (PD) and its application as full-spectrum optical sensor and pyroelectric nanogenerator (PENG) are demonstrated. The working mechanism of PDs for PENGs is carefully investigated and

• limits their application in the field of flexible electronics. Recently, the design of flexible devices with Si membranes as building blocks has been explored. These devices have become promising candidates for the use as flexible PDs due to many advantages, such as good compatibility, working in a harsh

• environment, low cost, and easy preparation [6][7][8][9]. However, the energy supply system of traditional Si-based flexible PDs utilizes an external battery, which will affect the portability, comfort, and durability of wearable devices due to large volume, and limited capacity. Therefore, it is necessary to

PTCDA adsorption on CaF₂ thin films

• Philipp Rahe

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

• functionality. Here, the molecular properties of 3,4,9,10-perylene tetracarboxylic dianhydride (PTCDA) adsorbed on insulating CaF2 thin films that were grown on Si(111) surfaces are studied. Scanning tunnelling microscopy is used to compare the properties of PTCDA molecules adsorbed on a partly CaF1-covered Si

• (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

• partially KBr-covered Ag(111) surfaces [24] as well as for cyanoporphyrin molecules on KBr-covered Cu(111) surfaces [26]. Here, the understanding of molecular adsorption on insulating thin films is extended by studying an insulator-on-semiconductor system, namely CaF2 thin films grown on Si(111) surfaces

High-responsivity hybrid α-Ag₂S/Si photodetector prepared by pulsed laser ablation in liquid

• Raid A. Ismail,
• Hanan A. Rawdhan and
• Duha S. Ahmed

Beilstein J. Nanotechnol. 2020, 11, 1596–1607, doi:10.3762/bjnano.11.142

• monodisperse Ag2S NPs when using the CTAB surfactant. The optoelectronic properties of α-Ag2S/p-Si photodetector, such as current–voltage characteristics and responsivity in the dark and under illumination, were also improved after using the CTAB surfactant. The responsivity of the photodetector increases from

• 0.64 to 1.85 A/W at 510 nm after adding CTAB. The energy band diagram of the α-Ag2S/p-Si photodetector under illumination was constructed. The fabricated photodetectors exhibited reasonable stability after three weeks of storage under ambient conditions with a responsivity of 70% of the initial value

• . synthesized monodisperse Ag2S NPs by using a sonochemical method and fabricated photodetector devices by integrating Ag2S NPs on a graphene sheet [17]. Tretyakov et al. [18] reported the characterization of a Ag2SQD (quantum dots)/Si heterojunction photodetector used for short-wave infrared radiation

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

• ] machined elliptic nanostructures with different parameters on Si substrates, including the spacing between structures and the thickness of the gold film. A spacing of 15 nm between the adjacent nanostructures was for the detection of R6G molecules with a concentration of 10−6 mol·L−1. Compared with other

• over a 20 × 20 μm2 area. Before the tests, the Raman spectra were rectified using a standard Si substrate. A Raman intensity peak of 1362 cm−1 for R6G was chosen in the experiment. An atomic force microscopy (AFM) system (Dimension Icon, Bruker, Germany) was employed to detect the two-dimensional and

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

• perpendicular to the surface has previously been observed for variety of molecules [37][38][39]. Many metal phthalocyanines have been shown to rotate on metal surfaces [40][41][42][43], but notably also a modified Co phthalocyanine on Si(100) [44]. Molecules sometimes come close enough to each other or can be

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

• stability and good biocompatibility [20]. The Si NPs enhance the bactericidal effects of some compounds, mainly metallic systems, against a broad range of microorganisms due to their easy delivery [20][140]. In addition, their surfaces can be easily modified by relatively inexpensive precursors which can

• increase their efficiency. Bactericidal properties of nitric-oxide-releasing Si NPs against P. aeruginosa, E. coli, S. aureus, S. epidermis, and Candida albicans were studied and the results indicated an increased antimicrobial effectiveness due to a greater amount of nitric oxide released by the Si NPs

• [141]. In addition, the antimicrobial efficiency of silver and copper nanoparticles have also been improved through the development of Si–Ag and Si–Cu NPs. This achievement is specifically important when NPs present cytotoxic effects. Silver NPs were immobilized on hollow silica nanospheres or

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

• metals (Au, Pt, Pd, Cu, and Ir) were investigated to derive a set of technologies as platform for specific applications. Especially, the shape of the 3D structures and the resulting reflectance have been investigated. The Si nanostructures fabricated using Au nanoparticles show a perfect light absorption

• electron vacancies play an important role within the anodic reactions at the silicon surface. The combined reaction can be written as: This reaction summarises two etching mechanisms related to n, the number of consumed holes h+ per etched Si atom. The first mechanism is correlated to n = 4. The silicon

• underneath the noble metal [13]. The second mechanism involves two holes (n = 2). Per etched Si atom one H2 molecule is formed. This etching mechanism is not limited to the metal–silicon interface and occurs in a wider area around the noble metal. This etching mechanism mainly results in nanoporous sponge

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

• /CaF1/Si(111) thin film samples under ultrahigh vacuum conditions (p < 5 × 10−10 mbar) in two separate systems equipped with appropriate facilities for in situ sample preparation. Bulk CaF2 crystals (Korth Kristalle, Altenholz, Germany) were cleaved in vacuum [24] after degassing the crystal and sample

• evaporator (Focus GmbH, Huenstetten, Germany) on freshly prepared Si(111)-(7 × 7) surfaces held at about 930 K. Silicon substrates were highly B-doped p-type Si(111) samples (Institute of Electronic Materials Technology, Warsaw, Poland) with the (7 × 7) reconstruction prepared by flash cycles. Further

• samples, the surface direction was determined by cleaving the crystal after the NC-AFM experiments along a (111) plane other than the surface plane. For thin film samples, the orientation of the Si(111)-(7 × 7) unit cell was measured by scanning tunnelling microscopy (STM) and the direction was

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

• the results for gold droplet formation on Si(111). A decrease in droplet number and an increase in droplet diameter with increasing temperature can be visualized. The droplet diameter distribution is described by a LSW distribution. Figure 3 shows scanning electron microscopy (SEM) and transmission

• were formed throughout the sample surface. The results for gold and germanium deposition onto a silicon substrate are shown in Figure 4c and Figure 4d, respectively. In Figure 4c, the gold droplets formed on the Si substrate were larger than the ones formed on the SiOx substrate (Figure 4b). When

• germanium was deposited onto Au/Si substrates, germanium nanowires were grown. The in-plane nanowires started to grow at places where the gold droplets had formed previously. The inset shows gold at the top of the germanium nanowire, where continuous homoepitaxial growth was catalysed. A sample with a

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

• . With this, we take the first steps toward enabling the creation of superior H–Si surfaces through an improved understanding of surface defects, ultimately leading to more consistent and reliable fabrication of atom scale devices. Keywords: atomic force microscopy; hydrogen-terminated silicon; scanning

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

• synthesized using a CVD microreactor method, described in detail in [33], directly on 285 nm SiO2/Si substrates, which also served as the back-gate in the FET configuration. MoS2 flakes were contacted with electrodes using standard electron beam lithography on polymethyl methacrylate (PMMA) resist, followed

Cryogenic low-noise amplifiers for measurements with superconducting detectors

• Ilya L. Novikov,
• Boris I. Ivanov,
• Dmitri V. Ponomarev and
• Aleksey G. Vostretsov

Beilstein J. Nanotechnol. 2020, 11, 1316–1320, doi:10.3762/bjnano.11.115

• Ilya L. Novikov Boris I. Ivanov Dmitri V. Ponomarev Aleksey G. Vostretsov Novosibirsk State Technical University, K.Marx-Av.20, Novosibirsk 630073, Russia 10.3762/bjnano.11.115 Abstract We designed, implemented, and characterized differential amplifiers for cryogenic temperatures based on Si

• low-frequency and low-noise amplifiers are commonly based on Si bipolar junction transistor (BJT) technology and junction field-effect transistor (JFET) technology. Since external interferences can be compensated by differential input circuits, differential amplifier designs are used for these

• applicability of commercially available Si bipolar transistors for cryogenics. Design and preliminary performance of cryogenic low-noise differential amplifiers, based on matched parallel connected pairs of commercially available bipolar junction transistors, at temperatures of 77 and 50 K are presented. This

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

• the pole piece and the sample. b, c) The cantilever (colorized in purple on the HIM images) can be navigated by making use of the large FOV image provided by the HIM. d) AFM height image of Si nanopillars taken in off-resonance tapping mode. Scale bar 5 µm. AFM height images of poly(methyl

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

• . It was calibrated using atomic force microscopy (AFM) [40]. The process begins with thermal oxidation of Si at 1000 °C using an oxidation furnace to obtain a thermally grown SiO2 layer followed by masking and etching to get the desired pattern. The polysilicon is deposited in a low-pressure chemical

3D superconducting hollow nanowires with tailored diameters grown by focused He⁺ beam direct writing

• Rosa Córdoba,
• Alfonso Ibarra,
• Dominique Mailly,
• Isabel Guillamón,
• Hermann Suderow and
• José María De Teresa

Beilstein J. Nanotechnol. 2020, 11, 1198–1206, doi:10.3762/bjnano.11.104

• transport study using the typical four-point-probe configuration has been performed. Following the procedure described in [17], first 3D NWs were placed flat on the SiO2 layer of a Si/SiO2 substrate by means of a nano-manipulator. Then, four Pt FIBID contacts were grown to connect the NWs to pre-patterned

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

• phthalocyanine molecules on graphene-covered SiO2/Si samples [5] as well as on h-BN-covered Ir(111) [6], of conjugated oligohenylenes on h-BN-covered Cu(111) [7], of manganese phthalocyanine on h-BN-covered Rh(111) [8], and of 5,10,15,20-tetraphenylbisbenz[5,6]indendo[1,2,3-cd:1′,2′,3′-lm]perylene on graphene

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

• , Germany 10.3762/bjnano.11.99 Abstract Tip-enhanced Raman spectroscopy is combined with polarization angle-resolved spectroscopy to investigate the nanometer-scale structural properties of core–shell silicon nanowires (crystalline Si core and amorphous Si shell), which were synthesized by platinum

• of the Raman peaks of crystalline Si and amorphous Si by applying tip-enhanced Raman spectroscopy, at sample positions being 8 nm apart. The local crystallinity revealed using confocal Raman spectroscopy and tip-enhanced Raman spectroscopy agrees well with the high-resolution transmission electron

• local structural properties of Si nanomaterials at the sub-10 nanometer scale using tip-enhanced Raman techniques. Keywords: core–shell nanowires; local crystallinity; polarization angle-resolved spectroscopy; silicon; tip-enhanced Raman spectroscopy; Introduction The properties of silicon are long

Applications of superparamagnetic iron oxide nanoparticles in drug and therapeutic delivery, and biotechnological advancements

• Maria Suciu,
• Corina M. Ionescu,
• Alexandra Ciorita,
• Septimiu C. Tripon,
• Dragos Nica,
• Hani Al-Salami and
• Lucian Barbu-Tudoran

Beilstein J. Nanotechnol. 2020, 11, 1092–1109, doi:10.3762/bjnano.11.94

Excitonic and electronic transitions in Me–Sb₂Se₃ structures

• Nicolae N. Syrbu,
• Victor V. Zalamai,
• Ivan G. Stamov and
• Stepan I. Beril

Beilstein J. Nanotechnol. 2020, 11, 1045–1053, doi:10.3762/bjnano.11.89

• and it does not refute the existence of indirect transitions given that more studies (like the ones made for Ge, Si, GaP, etc.) need to be performed in order to clarify those issues, ideally with purely grown crystals. We do not negate the existence of indirect transitions as we do not have such

Highly sensitive detection of estradiol by a SERS sensor based on TiO₂ covered with gold nanoparticles

• Andrea Brognara,
• Ili F. Mohamad Ali Nasri,
• Beatrice R. Bricchi,
• Andrea Li Bassi,
• Caroline Gauchotte-Lindsay,
• Matteo Ghidelli and
• Nathalie Lidgi-Guigui

Beilstein J. Nanotechnol. 2020, 11, 1026–1035, doi:10.3762/bjnano.11.87

• soaking in HAuCl4 solution, as composite SERS substrates for the detection of methylene blue. They reported a successful SERS enhancement, compared to bare Si substrates, with an enhancement factor of ca. 106 and a lower detection limit of 100 nM. Li et al. [15] studied Au NP-coated TiO2 nanotube arrays

• Si(100) and soda-lime glass substrates, which were mounted on a sample holder at a fixed target-to-substrate distance of 5 cm. Changing the background pressure within the deposition chamber allowed for a tuning of the film morphology (i.e., a higher pressure resulted in a higher film porosity) [28

• perform morphological characterizations of the films deposited on Si(100) substrates. The average size distribution of Au NPs was estimated through statistical analysis of top-view SEM images with the open source software ImageJ®. Since the shape of the Au NPs was not always perfectly circular, their area

Gas-sensing features of nanostructured tellurium thin films

• Dumitru Tsiulyanu

Beilstein J. Nanotechnol. 2020, 11, 1010–1018, doi:10.3762/bjnano.11.85

• sensing parameters did not differ much from the similar parameters obtained earlier for microcrystalline Te films. Further investigations have been extended to Te nanotubes grown on quartz or Si(111) substrates through a catalyst-free growing process in a furnace filled with argon [21]. Another study used

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

• at 1.32 eV is usually attributed to Si impurities at the Ga sites forming different complexes, such as (SiGaVGa) [28][29] or (SiGaGaAs) [30]. Since Si impurities exhibit an amphoteric behavior in GaAs, they give rise to an acceptor SiAs state in addition to the SiGa shallow donor state. The second PL

• our GaAs nanowire detector working in the photoconductor mode is by a factor of 1.5 better than the value obtained recently on molecular beam epitaxy (MBE)-grown Si-doped GaAs nanowires with a carrier concentration of 1.47 × 1017 cm−3, working in the field-effect transistor (FET) mode at similar

• suitable for the development of IR photodetectors with good sensitivity and dynamic characteristics. Experimental Electrochemical anodization. Crystalline 500 µm thick (111)-oriented substrates of Si-doped n-GaAs with a free electron concentration of 2 × 1018 cm−3 were used in this study. The samples were

A 3D-polyphenylalanine network inside porous alumina: Synthesis and characterization of an inorganic–organic composite membrane

• Jonathan Stott and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2020, 11, 938–951, doi:10.3762/bjnano.11.78

• Abstract Surface functionalization of porous materials allows for the introduction of additional functionality coupled with high mechanical stability of functionalized inner pores. Herein, we investigate the surface-initiated ring-opening polymerization (SI-ROP) of phenylalanine-N-carboxyanhydride (PA-NCA

• ; polyphenylalanine; porous alumina membranes; surface-initiated ring-opening polymerization (SI-ROP); Introduction Porous materials with functional surfaces are a topic of immense interest in science and technology. The high surface area and high mechanical stability of such materials allows for applications in

• applications. The most common route to graft polypeptides on surfaces is the surface-initiated ring-opening polymerization (SI-ROP) of α-aminoacid-N-carboxyanhydrides (NCAs). Dense polypeptide films consisting of poly(γ-benzyl-ʟ-glutamate), polylysine or polyphenylalanine with thickness in the range between