Gas-sensing features of nanostructured tellurium thin films

• Dumitru Tsiulyanu

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

• Dumitru Tsiulyanu CIMAN Research Centre of Department of Physics, Technical University, bul. Dacia 41, MD-2060 Chisinau, Moldova 10.3762/bjnano.11.85 Abstract Nanocrystalline and amorphous nanostructured tellurium (Te) thin films were grown and their gas-sensing properties were investigated at

• different operating temperatures with respect to scanning electron microscopy and X-ray diffraction analyses. It was shown that both types of films interacted with nitrogen dioxide, which resulted in a decrease of electrical conductivity. The gas sensitivity, as well as the response and recovery times

• , differed between these two nanostructured films. It is worth mentioning that these properties also depend on the operating temperature and the applied gas concentration on the films. An increase in the operating temperature decreased not only the response and recovery times but also the gas sensitivity of

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

• -dimensional fibrillar network with intrinsic porosity was formed in DCM, whereas in THF, a dense and smooth polypeptide film was observed. A post-treatment with a mixture of chloroform and dichloroacetic acid leads to rearrangement of the morphology of the grafted polymer films. The analysis by scanning

• electron microscopy (SEM), near-infrared spectroscopy (NIR) and contact angle measurements (CA) reveals a change in morphology of the grafted polymer films, which is due to the rearrangement of the secondary structure of the polypeptides. No significant loss of the surface-grafted polypeptides was

• determined by thermogravimetric (TG) measurements, which indicates that the change in morphology of the polymer films is solely a result of a conformational change of the surface-grafted polypeptides. Furthermore, adsorption of a test analyte (chloroanilic acid) was investigated with respect to different

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

• Politehnica of Bucharest, 060042-Bucharest, Romania Institute of Applied Physics, Chisinau MD-2028, Republic of Moldova National Center for Materials Study and Testing, Technical University of Moldova, Chisinau MD-2004, Republic of Moldova 10.3762/bjnano.11.75 Abstract A series of Zn1−xMgxO thin films with

• the composition range x = 0.00–0.40 has been prepared by sol–gel spin coating on Si substrates with a post-deposition thermal treatment in the temperature range of 400–650 °C. The morphology of the films was investigated by scanning electron microscopy and atomic force microscopy while their light

• emission properties were studied by photoluminescence spectroscopy under excitation at 325 nm. It was found that annealing at 500 °C leads to the production of macroscopically homogeneous wurtzite phase films, while thermal treatment at higher or lower temperature results in the degradation of the

Transition from freestanding SnO₂ nanowires to laterally aligned nanowires with a simulation-based experimental design

• Jasmin-Clara Bürger,
• Sebastian Gutsch and
• Margit Zacharias

Beilstein J. Nanotechnol. 2020, 11, 843–853, doi:10.3762/bjnano.11.69

• result, Choi et al. were able to measure an improved sensitivity for gas sensors made of tin oxide nanowires (SnO2 NWs) in comparison with powder-based SnO2 thin films [9]. For the use of NWs in electronic and sensor devices, freestanding NWs often have to be scratched off of the growth substrate

• substrates were prepared by two different preparation methods for the catalyst seeds, which are required for the VLS process. As a catalyst material, gold was chosen. First, a-plane sapphire substrates with structured gold thin films (thickness 5 nm) by metal evaporation, and second, a-plane sapphire

• Figure 5 compare the resulting NWs for two kind of samples (structured gold films, Figure 5a–c; gold nanoparticles, Figure 5d–f) for two different process pressures and powder temperatures. Especially for the nanowires from gold nanoparticles, a modification from freestanding to laterally aligned NWs is

Templating effect of single-layer graphene supported by an insulating substrate on the molecular orientation of lead phthalocyanine

• K. Priya Madhuri,
• Abhay A. Sagade,
• Pralay K. Santra and
• Neena S. John

Beilstein J. Nanotechnol. 2020, 11, 814–820, doi:10.3762/bjnano.11.66

• crystalline nonplanar MPcs are monoclinic and triclinic forms [5]. In thin films of MPcs, the molecules may attain face-on or edge-on orientations with respect to the substrate plane while forming the above crystal phases. The monoclinic fractions are known to have strong absorption in the visible range while

• intermolecular interactions on the top layers, influences the orientation of PbPc molecules leading to the formation of a very small fraction of triclinic moieties in edge-on or tilted configuration. Further, electrical characterization of these films in a vertical configuration shows enhanced conduction

Epitaxial growth and superconducting properties of thin-film PdFe/VN and VN/PdFe bilayers on MgO(001) substrates

• Wael M. Mohammed,
• Igor V. Yanilkin,
• Amir I. Gumarov,
• Airat G. Kiiamov,
• Roman V. Yusupov and
• Lenar R. Tagirov

Beilstein J. Nanotechnol. 2020, 11, 807–813, doi:10.3762/bjnano.11.65

• structure. We propose epitaxial single-crystalline thin films of VN and heteroepitaxial Pd1−xFex/VN and VN/Pd1−xFex (x ≤ 0.08) structures grown on MgO(001) as the materials of a choice for the improvement of superconducting magnetic random access memory characteristics. Keywords: epitaxial growth

• are indications of non-homogeneous, nanoclustered magnetism in Pd0.99Fe0.01 films grown on niobium [31], which may cause a shortening of the spin-memory length [32] and a reduction of the Josephson critical current. In general, the metallic Nb lattice (body-centered cubic with aNb = 329.4 pm) poorly

• matches that of the palladium-rich Pd1−xFex alloys (face-centered cubic with a0 = 389 pm). Therefore, a good crystallinity of the layer stack can hardly be expected. In the resulting polycrystalline films, crystallite boundaries and crystal lattice imperfections can lead to the segregation of iron

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

• aluminium oxide films and a metal layer (8 nm Cr and 25, 17.5 and 10 nm of Au), respectively. AAO films of different thickness were anodized and the Yxy values (Y is the luminance value, and x and y are the chromaticity values) were obtained via reflectance measurements. An empirical model based on the

• (AAO) films; anodization; structural colours; reflectance; polar coordinates; plasmonic effects; Introduction Recently, the reproduction of the vivid colours found in nature has received increasing interest [1]. These colours appear when light interacts with periodic structures. With regard to this

• , anodic aluminium oxide films play an important role. There are different approaches in obtaining brilliant colours using AAO films, such as the use of new anodization electrolytes (etidronic acid) [2], the use of pulsed anodization [3], and the deposition of a metal layer onto the surface of AAO–Al films

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

• , with widespread ZPLs from UV to NIR, which limits the potential development of h-BN-based devices and applications and their controllable formation. In [109], it is shown that in CVD large-area, few-layer h-BN films, more than 85% of the emitters have a ZPL at (580 ± 10) nm, while maintaining a high

• between multilayer flakes and CVD monolayers, where the former has a larger observed density of defects and ZPLs. CVD monolayer h-BN SPEs were studied in [45] after treatment and their ZPLs were reported in the range of 583–691 nm. Using low-pressure CVD [108][109], large-area, few-layer h-BN films can be

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

• template (AAO) has constituted an important advance in the field of film preparation, since it allows the formation of nanostructured films with a high degree of morphology control [22]. Furthermore, according to Das et al. [23], the use of atomic layer deposition (ALD) for the preparation of TiO2 films

• affords specimens with different electron transfer characteristics than those of rutile and anatase TiO2, and the as-prepared films fit the template well. When Ag particles are combined with TiO2, the photocatalytic performance of the film can be significantly enhanced by hot electron injection [24

Structural optical and electrical properties of a transparent conductive ITO/Al–Ag/ITO multilayer contact

• Aliyu Kabiru Isiyaku,
• Ahmad Hadi Ali and
• Nafarizal Nayan

Beilstein J. Nanotechnol. 2020, 11, 695–702, doi:10.3762/bjnano.11.57

• for transparent conductive oxide (TCO) films due to its good optical and electrical properties. Improving the optoelectronic properties of ITO films with reduced thickness is crucial and quite challenging. ITO-based multilayer films with an aluminium–silver (Al–Ag) interlayer (ITO/Al–Ag/ITO) and a

• pure ITO layer (as reference) were prepared by RF and DC sputtering. The microstructural, optical and electrical properties of the ITO/Al–Ag/ITO (IAAI) films were investigated before and after annealing at 400 °C. X-ray diffraction measurements show that the insertion of the Al–Ag intermediate bilayer

• led to the crystallization of an Ag interlayer even at the as-deposited stage. Peaks attributed to ITO(222), Ag(111) and Al(200) were observed after annealing, indicating an enhancement in crystallinity of the multilayer films. The annealed IAAI film exhibited a remarkable improvement in optical

Electromigration-induced directional steps towards the formation of single atomic Ag contacts

• Atasi Chatterjee,
• Christoph Tegenkamp and
• Herbert Pfnür

Beilstein J. Nanotechnol. 2020, 11, 680–687, doi:10.3762/bjnano.11.55

• detail previously. Contrary to most EM experiments with thin metallic films on insulating substrates, the Ag/Si(100) system is unique in the sense that the first Ag layer wets the hydrogen-terminated Si(100) surface [25]. This improves the thermal contact so that thermally assisted processes during EM

• can be suppressed to a large extent, in agreement with our own simulations [26]. This situation differs from most previous EM experiments, in which it was difficult to separate EM from thermal effects. For our experiments we use ultrathin Ag films (thickness 5 nm), which exhibit Stranski–Krastanov

• , studied here in detail, is less well defined than in single-crystalline materials. Therefore, the question arises whether a well-defined growth direction can be identified at all. Our answer is positive. Furthermore, we were recently able to demonstrate very different morphologies upon EM of such films

Observation of unexpected uniaxial magnetic anisotropy in La_2/3Sr_1/3MnO₃ films by a BaTiO₃ overlayer in an artificial multiferroic bilayer

• John E. Ordóñez,
• Lorena Marín,
• Luis A. Rodríguez,
• Pedro A. Algarabel,
• José A. Pardo,
• Roger Guzmán,
• Luis Morellón,
• César Magén,
• Etienne Snoeck,
• María E. Gómez and
• Manuel R. Ibarra

Beilstein J. Nanotechnol. 2020, 11, 651–661, doi:10.3762/bjnano.11.51

• using the pulsed-laser deposition technique. We analyzed the films structurally through X-ray reciprocal space maps and high-angle annular dark field microscopy, and magnetically via thermal demagnetization curves and in-plane magnetization versus applied magnetic field loops at room temperature. Our

• results indicate that the BaTiO3 layer induces an additional strain in the La2/3Sr1/3MnO3 layers close to their common interface. The presence of BaTiO3 on the surface of tensile-strained La2/3Sr1/3MnO3 films transforms the in-plane biaxial magnetic anisotropy present in the single layer into an in-plane

• ; magnetic anisotropy; Introduction In recent years, enormous interest has been shown in the multiferroic properties of the multilayered system based on La2/3Sr1/3MnO3 (LSMO) and BaTiO3 (BTO) films [1][2][3][4][5]. Each perovskite material has a particular ferroic order at room temperature, i.e

Luminescent gold nanoclusters for bioimaging applications

• Nonappa

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

• luminescent nanomaterials [30]. Despite the early discovery of the luminescence phenomenon in bulk gold and gold films, the PL of gold remained unexplored for several decades [31][32]. This is attributed to the low quantum yield (10−10), which limited the practical application and the understanding of the

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

• release of therapeutic agents upon minor variations in the environmental characteristics, surface modification and suppression of inter-chain interaction to the degradation/rearrangement of LbL films under the action of physical factors [19][20]. In spite of the fact that weak PE systems can also offer

• prominent when there are many charged groups present in the system. The use of different charged groups for LbL assembly can impart unique responsiveness to LbL systems as the residual charges in the multilayer films can play an important role in manipulating the polymer/polymer interactions, thus leading

• studied by using anionic fluorescent probes [42]. The amount of probe bound to an existing layer was linearly dependent on the thickness of multilayers up to 15 nm, and thereafter highly overlapped layers instead of well separated films were observed. Even when the outermost layer was negatively charged

Evolution of Ag nanostructures created from thin films: UV–vis absorption and its theoretical predictions

• Robert Kozioł,
• Marcin Łapiński,
• Paweł Syty,
• Damian Koszelow,
• Wojciech Sadowski,
• Józef E. Sienkiewicz and
• Barbara Kościelska

Beilstein J. Nanotechnol. 2020, 11, 494–507, doi:10.3762/bjnano.11.40

• Narutowicza 11/12, 80-233 Gdansk, Poland 10.3762/bjnano.11.40 Abstract Ag-based plasmonic nanostructures were manufactured by thermal annealing of thin metallic films. Structure and morphology were studied using scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution

• : dewetting; finite-difference time-domain (FDTD) method; plasmon resonance; silver (Ag) nanostructures; thin films; UV–vis absorption; Introduction In the last decade there has been significant development in sensor-related research regarding the application in optical, medical or biological areas [1][2][3

• resonance over a wide frequency range. There are many methods for the fabrication of metal nanostructures. One promising technique is the heating of thin metallic films deposited on a substrate. These layers are metastable and can undergo dewetting with increasing temperature. Dewetting can occur via three

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

• enable the use of 2D materials in technology applications, processes have been developed to grow 2D materials via chemical vapour deposition (CVD) [16][17] and atomic layer deposition (ALD) [18][19]. The films prepared via thin film deposition were comparable in performance to materials obtained via

Formation of nanoripples on ZnO flat substrates and nanorods by gas cluster ion bombardment

• Xiaomei Zeng,
• Vasiliy Pelenovich,
• Bin Xing,
• Rakhim Rakhimov,
• Wenbin Zuo,
• Alexander Tolstogouzov,
• Chuansheng Liu,
• Dejun Fu and
• Xiangheng Xiao

Beilstein J. Nanotechnol. 2020, 11, 383–390, doi:10.3762/bjnano.11.29

• -enhanced Raman spectroscopy [4]. Ion beam formation of nanoscale ripples has emerged as a versatile method to imprint uniaxial magnetic anisotropy [5] and to control the magnetic texture of thin films [6]. Formation of self-assembled surface nanoripple structures by monoatomic off-normal ion irradiation

• substrates have been employed, such as Si wafers, bulk Au samples or SiO2 films. There are very few papers on the ripple formation on the surface of confined nanostructures both by monoatomic and cluster ion irradiation. Therefore, in this research we study features of nanoripple formation on the facets of

• developed and wavelength and height of the ripples calculated from the bottom drift line surface increase (Figure 4b and Table 1). This behavior is in agreement with data obtained for SiO2 films and gold surfaces bombarded with Ar clusters [19][22]. The process of ripple formation is triggered by the

Poly(1-vinylimidazole) polyplexes as novel therapeutic gene carriers for lung cancer therapy

• Gayathri Kandasamy,
• Elena N. Danilovtseva,
• Vadim V. Annenkov and
• Uma Maheswari Krishnan

Beilstein J. Nanotechnol. 2020, 11, 354–369, doi:10.3762/bjnano.11.26

• to the proton-donating nature of the imidazole moiety have been demonstrated in [9]. Imidazole-based hydrogel films demonstrated excellent anti-microbial effects [10]. A copolymer of poly(acrylamide) and poly(vinylimidazole) was used as a hydrophilic matrix to disperse multiwalled carbon nanotubes

Implementation of data-cube pump–probe KPFM on organic solar cells

• Benjamin Grévin,
• Olivier Bardagot and
• Renaud Demadrille

Beilstein J. Nanotechnol. 2020, 11, 323–337, doi:10.3762/bjnano.11.24

• less data points to probe the parts of the time-domain where the SP evolves more slowly. Organic BHJ Solar Cells In this work, PTB7:PC71BM BHJ photovoltaic thin films have been used as test samples (Figure 3) for pp-KPFM experiments. In the following, a few concepts of organic photovoltaics are

• of the solvent and additives used for the film deposition from solution. The use of PTB7:PC71BM is widely documented. It is now well established that films of good morphology, namely with a nanoscale phase separation, can be obtained from solutions containing 1,8-diiodooctane (DIO) as solvent

• -based devices, hybrid perovskite thin films and single crystals as well as type-II van der Waals heterojunctions based on transition metal dichalcogenides. Experimental Nc-AFM and pp-KPFM Noncontact-AFM (nc-AFM) experiments were performed with a ScientaOmicron VT-AFM setup in UHV at room temperature (RT

Using gold nanoparticles to detect single-nucleotide polymorphisms: toward liquid biopsy

• María Sanromán Iglesias and
• Marek Grzelczak

Beilstein J. Nanotechnol. 2020, 11, 263–284, doi:10.3762/bjnano.11.20

• capable of quenching fluorescence through Förster resonance energy transfer. By involving an isothermal circular amplification reaction of polymerase and NEase, the group of Chen [121] used gold nanoparticles to either quench or enhance the electrochemiluminescence of CdS films through the modulation of

• oligonucleotides. The presence of a mutation decreases the fluorescence of the CdS films by nearly 90%. Reprinted with permission from [121], copyright 2011 Royal Society of Chemistry. Colorimetric DNA detection through rolling circle amplification (RCA) and NEase-assisted nanoparticle amplification (NEANA). a

Fabrication of Ag-modified hollow titania spheres via controlled silver diffusion in Ag–TiO₂ core–shell nanostructures

• Bartosz Bartosewicz,
• Malwina Liszewska,
• Bogusław Budner,
• Marta Michalska-Domańska,
• Krzysztof Kopczyński and
• Bartłomiej J. Jankiewicz

Beilstein J. Nanotechnol. 2020, 11, 141–146, doi:10.3762/bjnano.11.12

• TiO2 nanostructures has been only investigated in the case of TiO2 thin films [8][21][22][23][24] and our studies are probably the first to discuss this process occurring in Ag@TiO2 CSNs. Based on our results and the diffusion mechanism proposed for AgNPs on titania films [8][21], the silver diffusion

Nanosecond resistive switching in Ag/AgI/PtIr nanojunctions

• Botond Sánta,
• Dániel Molnár,
• Patrick Haiber,
• Agnes Gubicza,
• Edit Szilágyi,
• Zsolt Zolnai,
• András Halbritter and
• Miklós Csontos

Beilstein J. Nanotechnol. 2020, 11, 92–100, doi:10.3762/bjnano.11.9

• following the method of Kumar and co-workers [36]. The Ag films were evaporated on standard Si/SiO2 wafers using a 12 nm thick Ti sticking layer. The structural characterization of the thin film samples was carried out by Rutherford backscattering spectrometry (RBS) using an ion beam of 3500 keV 4He

The effect of heat treatment on the morphology and mobility of Au nanoparticles

• Sven Oras,
• Sergei Vlassov,
• Simon Vigonski,
• Boris Polyakov,
• Mikk Antsov,
• Vahur Zadin,
• Rünno Lõhmus and
• Karine Mougin

Beilstein J. Nanotechnol. 2020, 11, 61–67, doi:10.3762/bjnano.11.6

• Si wafers were prepared, and four of them were then separately annealed in an oven for 1 h at 200, 400, 600 and 800 °C while the fifth was left untreated. Separate samples were prepared on heat-resistant silicon nitride support films of 50 nm membrane thickness (Pelco, Ted Pella) to be used for

Recent progress in perovskite solar cells: the perovskite layer

• Xianfeng Dai,
• Ke Xu and
• Fanan Wei

Beilstein J. Nanotechnol. 2020, 11, 51–60, doi:10.3762/bjnano.11.5

• components in next-generation photovoltaic technology due to their high efficiency and low cost. In this article, recent progress in the development of perovskite layers, which are the basis of PSCs, is reviewed. Achievements in the fabrication of high-quality perovskite films by various methods and

• techniques are introduced. The reported works demonstrate that the power conversion efficiency of the perovskite layers depends largely on their morphology and the crystalline quality. Furthermore, recent achievements concerning the scalability of perovskite films are presented. These developments aim at

• control the film morphology and the crystalline quality and to prepare high-quality perovskite films with complete surface coverage, uniform morphology and large well-crystallized grains [13][14][15][16]. At the same time, research also focuses on the preparation of large-area perovskite films of high

Synthesis of amorphous and graphitized porous nitrogen-doped carbon spheres as oxygen reduction reaction catalysts

• Maximilian Wassner,
• Markus Eckardt,
• Andreas Reyer,
• Thomas Diemant,
• Michael S. Elsaesser,
• R. Jürgen Behm and
• Nicola Hüsing

Beilstein J. Nanotechnol. 2020, 11, 1–15, doi:10.3762/bjnano.11.1

• of the catalyst films of NCS and g-NCS (without catalyst film: 2 Ω). ORR onset potentials (potential value at 0.1 mA·cm−2) of the NCS and g-NCS catalysts in the ORR measurements in Figure 8. Acknowledgements This work was supported by the FWF Austrian Science Fund [I 1259–N28] and the Deutsche