Assessment of the optical and electrical properties of light-emitting diodes containing carbon-based nanostructures and plasmonic nanoparticles: a review

• Keshav Nagpal,
• Erwan Rauwel,
• Frédérique Ducroquet and
• Protima Rauwel

Beilstein J. Nanotechnol. 2021, 12, 1078–1092, doi:10.3762/bjnano.12.80

• market as they suffer from energy losses due to total internal reflection at the emitter/air interface. Several methods have been proposed to tune the properties of LED. To that end, multiwall carbon nanotubes (MWNT) and single-wall carbon nanotubes (SWNT) have been applied to various layers in LED, such

• as the emissive layer (EML), the hole transport layers (HTL), the electron transport layers (ETL), the cathode, and the anode [17][18][19][20][21]. Enhancement in LED properties via surface plasmon resonance (SPR) of metal nanoparticles (MNP) such as Au and Ag have also been reported [22][23]. This

• feasibility of incorporating GR and CNT in large-scale devices is also discussed. Even though plasmonic nanoparticles (NP) are a developing field, their applications are nonetheless promising. The effect of these nanostructures on the performance of LED when included in individual layers (i.e., anode, HTL

An overview of microneedle applications, materials, and fabrication methods

• Zahra Faraji Rad,
• Philip D. Prewett and
• Graham J. Davies

Beilstein J. Nanotechnol. 2021, 12, 1034–1046, doi:10.3762/bjnano.12.77

• fabricated using reshaped photoresist technology to form a channel inside (Figure 5c). The microneedle had a 1500 μm long shaft with a 45° angle tapered tip and a 1000 μm long pedestal. The manufacture comprised of repetitive patterning of the substrates by electroplating metal layers with multiple

Progress and innovation of nanostructured sulfur cathodes and metal-free anodes for room-temperature Na–S batteries

• Marina Tabuyo-Martínez,
• Bernd Wicklein and
• Pilar Aranda

Beilstein J. Nanotechnol. 2021, 12, 995–1020, doi:10.3762/bjnano.12.75

• methodology is more prone to generate rather thick and bulky sulfur layers, the latter can produce fine particles down to molecular sulfur species (S8) deposited on and within porous host materials [53]. Many cathodes of Na–S batteries are fabricated by the impregnation approach. In a recent work, 10 nm S NPs

A Au/CuNiCoS₄/p-Si photodiode: electrical and morphological characterization

• Adem Koçyiğit,
• Adem Sarılmaz,
• Teoman Öztürk,
• Faruk Ozel and
• Murat Yıldırım

Beilstein J. Nanotechnol. 2021, 12, 984–994, doi:10.3762/bjnano.12.74

• have revealed that the bandgap value is suitable for optoelectronic devices. To the best of our knowledge, there is no study on the electrical properties of CuNiCoS4-based photodiodes. The usage of different materials as interfacial layers in metal–semiconductor devices is a hot research topic

• ± 1 nm. An interplanar spacing of d = 2.87 Å, corresponding to the (113) planes of the cubic crystal structure, was determined from the HR-TEM image in Figure 2c. Figure 2d shows a FE-SEM images of the agglomerated nanocrystals. The surface of the CuNiCoS4 nanocrystal layers is smooth and free from

• results of the CuNiCoS4 nanocrystals confirmed that the nanocrystals are suitable for interfacial layers of photodiodes. Optical properties The optical properties of CuNiCoS4 nanocrystals were investigated by absorbance and diffuse reflectance spectroscopy (Figure 3). As can be seen in Figure 3a, the

Is the Ne operation of the helium ion microscope suitable for electron backscatter diffraction sample preparation?

• Annalena Wolff

Beilstein J. Nanotechnol. 2021, 12, 965–983, doi:10.3762/bjnano.12.73

Uniform arrays of gold nanoelectrodes with tuneable recess depth

• Elena O. Gordeeva,
• Ilya V. Roslyakov,
• Alexey P. Leontiev,
• Alexey A. Klimenko and
• Kirill S. Napolskii

Beilstein J. Nanotechnol. 2021, 12, 957–964, doi:10.3762/bjnano.12.72

• nanowires are electrically connected both to the bottom and the top continuous Cu layers (Figure 1c). According to [27], the decrease in electrodeposition overpotential, which is accompanied by the decrease in the diffusion current contribution, leads to an increase in the number of nanowires that reach the

• segments having electrical connection both with the bottom and the top continuous Cu layers are formed. Formation and characterization of NEAs After all the steps described above, the obtained NEAs consisted of the following components: the Cu layer sputtered on the AAO bottom side, short Cu, short Au, and

• diffusion layers results in the planar diffusion to the NEA surface. Thus, a decrease in the density of active electrodes could be more appropriate because of the decrease in electric double layer charging current and, as a consequence, the growth of the signal-to-noise ratio. A controlled decrease in the

Molecular assemblies on surfaces: towards physical and electronic decoupling of organic molecules

• Sabine Maier and
• Meike Stöhr

Beilstein J. Nanotechnol. 2021, 12, 950–956, doi:10.3762/bjnano.12.71

• of the substrate, for instance by adding or intercalating a decoupling layer, are often the better choice. In the best case, these interfacial layers have a large bandgap to prevent a hybridization with molecular states as well as with the metallic/semiconducting substrate. All the strategies for

• physical and electronic decoupling have been developed in view of fundamental studies as well as application in devices. Ultrathin semiconducting or insulating decoupling layers can be epitaxially grown as mono- and multilayers on many metallic substrates by either physical or chemical vapor deposition

• . Among others, ultrathin dielectric layers of either alkali halides (e.g., NaCl [17]) or metal oxides (e.g., MgO [18], Al2O3 [19], and CuO [20]), or nitrides (CuN [21]) have been shown to be beneficial for successfully reducing or even completely switching off the unwanted interaction between the metal

Self-assembly of Eucalyptus gunnii wax tubules and pure ß-diketone on HOPG and glass

• Miriam Anna Huth,
• Axel Huth and
• Kerstin Koch

Beilstein J. Nanotechnol. 2021, 12, 939–949, doi:10.3762/bjnano.12.70

• least 2% of diols [25]. The expected arrangements of the tubule-forming molecules are bended layers of nonacosanol and alkanediol. Within these layers, the hydroxyl groups of the alcohol molecules function as spacers in the tightly packed layer, leading to a curvature of the layer and eventually to the

• amplitude data of AFM measurements were processed and analyzed with JPK data processing software (version 4.2.62). The height of the tubules and the thickness of the layers were investigated using the cross section function of the processing software. The tubule height was calculated by averaging the height

• differences between the maximum tubule length to the left-side base and to the right-side base of the tubule. The height growth velocity of the tubules was calculated by linear regression lines of the height values as a function of time. The thickness of the layers (n = 10) was measured by the mean value of

The role of deep eutectic solvents and carrageenan in synthesizing biocompatible anisotropic metal nanoparticles

• Nabojit Das,
• Akash Kumar and
• Raja Gopal Rayavarapu

Beilstein J. Nanotechnol. 2021, 12, 924–938, doi:10.3762/bjnano.12.69

• ]. The difference between the electrochemical double layers and a differential activity of chloride ions (i.e., preferential facet binding during crystal growth restricting the lattice growth in a particular direction) were responsible for the observed morphological difference. The lower surface tension

In situ transport characterization of magnetic states in Nb/Co superconductor/ferromagnet heterostructures

• Olena M. Kapran,
• Roman Morari,
• Taras Golod,
• Evgenii A. Borodianskyi,
• Vladimir Boian,
• Andrei Prepelita,
• Nikolay Klenov,
• Anatoli S. Sidorenko and
• Vladimir M. Krasnov

Beilstein J. Nanotechnol. 2021, 12, 913–923, doi:10.3762/bjnano.12.68

• demonstrate how FORC can be used for detailed in situ characterization of magnetic states. It reveals that upon reduction of the external field, the magnetization in ferromagnetic layers first rotates in a coherent scissor-like manner, then switches abruptly into the antiparallel state and after that splits

• relative orientation of magnetizations in several F-layers [18][19][22][23][25][26][27][28][29][30][31][32][33][34][35]. However, the practical realization of such devices is complicated because neither ways of controlling many degrees of freedom in S/F multilayers, nor methods for monitoring magnetic

• microstructured Nb/Co multilayers (MLs) with a different number of F-layers and layer thicknesses. Our goal is to demonstrate how conventional experimental techniques can be used for in situ assessment of magnetic states of small S/F devices. The key technique that we employ is the first-order-reversal-curves

Modification of a SERS-active Ag surface to promote adsorption of charged analytes: effect of Cu²⁺ ions

• Bahdan V. Ranishenka,
• Andrei Yu. Panarin,
• Irina A. Chelnokova,
• Sergei N. Terekhov,
• Peter Mojzes and
• Vadim V. Shmanai

Beilstein J. Nanotechnol. 2021, 12, 902–912, doi:10.3762/bjnano.12.67

• deposited onto a PEI-modified silicon conductive support by adsorptive immobilization. Immobilization kinetics of Ag NPs on a glass substrate. Since the glass slides were modified on both sides, the spectra correspond to the absorption of two NPs layers. SEM image of Ag NPs immobilized on silicon surface by

The role of convolutional neural networks in scanning probe microscopy: a review

• Ido Azuri,
• Irit Rosenhek-Goldian,
• Neta Regev-Rudzki,
• Georg Fantner and
• Sidney R. Cohen

Beilstein J. Nanotechnol. 2021, 12, 878–901, doi:10.3762/bjnano.12.66

• boundary line in Figure 1). Then, a non-linear function is applied for each neuron. Without this step, termed “activation” (see below), multiple layers add no new knowledge to the problem. This non-linear function enables the neural network to learn complex non-linear decision boundaries instead of the

• linear decision boundaries, and prevents it from collapsing to a neural network without hidden layers. Application of this linear decision boundary has no benefit over logistic/linear regression, which is used for classification/regression in supervised machine learning. The weights and biases are

• , and pooling layers together form an operation block. Usually, this block is applied several times. Each block corresponds to a hidden layer. The number of filters can be increased or remain the same in each successive block, and the feature maps are down-sampled leading to dimension reduction while

Effects of temperature and repeat layer spacing on mechanical properties of graphene/polycrystalline copper nanolaminated composites under shear loading

• Chia-Wei Huang,
• Man-Ping Chang and
• Te-Hua Fang

Beilstein J. Nanotechnol. 2021, 12, 863–877, doi:10.3762/bjnano.12.65

• ]. Therefore, the design of ordered graphene composites and the development of optimized microstructures is a major issue to study. In 2013, Kim et al. synthesized metal–graphene nanolayered (MGNL) composites consisting of alternating metal (copper or nickel) layers and graphene monolayers [22]. Since then, a

• the mechanical properties of carbon materials [31]. In this study, graphene with zigzag and armchair chirality is considered while simulating different properties of graphene monolayers and copper layers, including stress–strain curve variations, the distribution of von Mises stress, the evolution of

• specific strain. In the case of the GPCuNL composite at 300 K, the shear stress drops suddenly when the strain is 0.39. Because the two layers of graphene do not fracture at the same time, a plateau appears in the curve followed by another drop at γ = 0.415, indicating another graphene failure. Furthermore

Comprehensive review on ultrasound-responsive theranostic nanomaterials: mechanisms, structures and medical applications

• Sepand Tehrani Fateh,
• Lida Moradi,
• Elmira Kohan,
• Michael R. Hamblin and
• Amin Shiralizadeh Dezfuli

Beilstein J. Nanotechnol. 2021, 12, 808–862, doi:10.3762/bjnano.12.64

Silver nanoparticles nucleated in NaOH-treated halloysite: a potential antimicrobial material

• Yuri B. Matos,
• Rodrigo S. Romanus,
• Mattheus Torquato,
• Edgar H. de Souza,
• Rodrigo L. Villanova,
• Marlene Soares and
• Emilson R. Viana

Beilstein J. Nanotechnol. 2021, 12, 798–807, doi:10.3762/bjnano.12.63

• smaller than that of the silver peaks, suggesting no stacking of halloysite layers in the composite. Figure 4 shows TEM images of halloysite substrate samples and of samples that went through the thermal reduction of silver. Images of HNT-0, HNT-4, and HNT-8 (Figure 4a,c,e) show that the NaOH treatment

Reducing molecular simulation time for AFM images based on super-resolution methods

• Zhipeng Dou,
• Jianqiang Qian,
• Yingzi Li,
• Rui Lin,
• Jianhai Wang,
• Peng Cheng and
• Zeyu Xu

Beilstein J. Nanotechnol. 2021, 12, 775–785, doi:10.3762/bjnano.12.61

• Lennard–Jones (LJ) potential is used to describe the interaction between the graphene layers and the tip substrate. The LJ parameters for C–C are εC–C = 2.84 meV, σC–C = 0.34 nm and for Si–C the parameters are εSi–C = 8.909 meV, σSi–C = 0.3326 nm (ε is the depth of the potential well, σ is the finite

• SRCNN is a representative method for deep learning super-resolution techniques and consists of three layers. This method uses bicubic interpolation as the preprocessing step and, then, extracts overlapping image blocks as high-dimensional vectors with the same dimension as the feature image through

• to reconstruct the complete image. The flow chart of the proposed SRCNN reconstruction method. First, the low-resolution simulated image is obtained, then the SRCNN method is used to reconstruct the high-resolution image. The SRCNN consists of three layers to implement feature extraction, non-linear

9.1% efficient zinc oxide/silicon solar cells on a 50 μm thick Si absorber

• Rafal Pietruszka,
• Bartlomiej S. Witkowski,
• Monika Ozga,
• Katarzyna Gwozdz,
• Ewa Placzek-Popko and
• Marek Godlewski

Beilstein J. Nanotechnol. 2021, 12, 766–774, doi:10.3762/bjnano.12.60

• inexpensive alternatives for indium tin oxide (ITO) [9]. In this work, we used ALD to deposit zinc oxide nanoseeds, magnesium-doped zinc oxide (MZO) layers and aluminium-doped zinc oxide films. We thus continue our interest on photovoltaic structures based on thin films of ZnO. Recently, there have been

Recent progress in magnetic applications for micro- and nanorobots

• Ke Xu,
• Shuang Xu and
• Fanan Wei

Beilstein J. Nanotechnol. 2021, 12, 744–755, doi:10.3762/bjnano.12.58

• with different magnetisms with applications in, for example, energy-saving logic, sensors, environmental remediation, and data storage [52]. Chen et al. [53] studied compensated magnetic heterostructures containing ferrimagnetic CoGd alloys and antiferromagnetic IrMn layers. The terahertz emission from

Prediction of Co and Ru nanocluster morphology on 2D MoS₂ from interaction energies

• Cara-Lena Nies and
• Michael Nolan

Beilstein J. Nanotechnol. 2021, 12, 704–724, doi:10.3762/bjnano.12.56

• made up of two layers. To create the pristine ML one of these was removed, which also creates the vacuum necessary to avoid interaction along the z-axis; the vacuum region is 8 Å. A (5 × 5) super cell was used. No van der Waals (vdW) corrections were applied, as both the literature and our own tests

Electromigration-induced formation of percolating adsorbate islands during condensation from the gaseous phase: a computational study

• Alina V. Dvornichenko,
• Vasyl O. Kharchenko and
• Dmitrii O. Kharchenko

Beilstein J. Nanotechnol. 2021, 12, 694–703, doi:10.3762/bjnano.12.55

• according to the Stransky–Krastanov growth regime [16][17][18][19], whereas at elevated temperatures such processes are associated with the solid dissolution of the layers of precipitated material [20][21]. Surface EM [22][23] is widely used in the study of thin solid films, for example, for the formation

• leading to a growth of multilayer adsorbate islands due to pairwise attractive interaction between adatoms. In such a case the reaction term R(x) should take into account the term ft responsible for the transitions of adatoms between neighboring layers, representing vertical diffusion. These transitions

• computed by solving the appropriate electrostatic boundary value problem [74]. In the present study we aimed to analyze a change in the morphology of the thin film on a substrate (first growing layer), assuming that upper layers will repeat the morphology of the first one. In this connection, we simplify

A review of defect engineering, ion implantation, and nanofabrication using the helium ion microscope

• Frances I. Allen

Beilstein J. Nanotechnol. 2021, 12, 633–664, doi:10.3762/bjnano.12.52

• junctions by the HIM method has again been demonstrated [48]. Ferromagnetic properties The first demonstration of defect engineering using the HIM was actually for a magnetic device by Franken and co-authors [49]. In this work, ferromagnetic microstrips comprising Pt(4 nm)/Co(0.6 nm)/Pt(2 nm) layers on an

• implementing doses up to 1 × 1017 ions/cm2, stripe patterns were irradiated onto a magnetic thin film structure (this time comprising a ferro- and an antiferromagnetic layer) [53]. The reason for using the higher doses was to investigate the effect of helium implantation and subsequent swelling of the layers

• and the underlying substrate on the magnetic modification obtained. It was found that helium ion bombardment influenced the magnetic anisotropy in both layers of the structure, strongly reducing the saturation magnetization of the layer system. Moreover, the behavior observed correlated with both the

Stability and activity of platinum nanoparticles in the oxygen electroreduction reaction: is size or uniformity of primary importance?

• Kirill O. Paperzh,
• Anastasia A. Alekseenko,
• Vadim A. Volochaev,
• Ilya V. Pankov,
• Olga A. Safronenko and
• Vladimir E. Guterman

Beilstein J. Nanotechnol. 2021, 12, 593–606, doi:10.3762/bjnano.12.49

• friendliness, low operating temperature, and high adaptability of specific characteristics [1][2][3]. The key components of PEMFC membrane–electrode assemblies (MEA) are the proton-exchange polymer membrane and porous electrode layers, in which current-forming reactions of oxygen electroreduction (ORR) and

• best choice [6][7][8]. The most important functional characteristics of the catalytic layers are their activity in the corresponding reactions and stability, which reflects the ability to maintain its activity during operation. These characteristics depend on the PEMFC operating conditions, the

• composition and structure of the catalytic layers, and the catalysts themselves [9]. Platinum–carbon catalysts, whose composition and structure determine their functional characteristics, are the key components of MEA catalytic layers. Of particular importance is the study of the catalyst electrochemical

Impact of GaAs(100) surface preparation on EQE of AZO/Al₂O₃/p-GaAs photovoltaic structures

• Piotr Caban,
• Rafał Pietruszka,
• Jarosław Kaszewski,
• Monika Ożga,
• Bartłomiej S. Witkowski,
• Krzysztof Kopalko,
• Piotr Kuźmiuk,
• Katarzyna Gwóźdź,
• Ewa Płaczek-Popko,
• Krystyna Lawniczak-Jablonska and
• Marek Godlewski

Beilstein J. Nanotechnol. 2021, 12, 578–592, doi:10.3762/bjnano.12.48

• ) properties and bandgap measurements of the deposited layers were also reported. The highest EQE value was obtained for the samples initially etched with a citric acid-based etchant and, in the last preparation step, either passivated with ammonium sulfide aqueous solution or treated with ammonium hydroxide

• ). For the etching of native oxide and suboxide gallium arsenide layers, 50 g of citric acid monohydrate (CA) C6H8O7·H2O (CAS: 5949-29-1) was dissolved into 50 mL of DIW. Since this is an endothermic reaction, the solution temperature initially dropped to approx. 8 °C. Further stirring for several

• passivation layer in the first few ALD cycles. By applying ALD, we were able to create both Al2O3 and AZO layers in a single ALD process conducted at 160 °C. Aluminum oxide was deposited within five cycles of (trimethylaluminum/Al(CH3)3, TMA, CAS:75-24-1) and H2O precursor supply while AZO required 10 multi

Properties of graphene deposited on GaN nanowires: influence of nanowire roughness, self-induced nanogating and defects

• Jakub Kierdaszuk,
• Piotr Kaźmierczak,
• Justyna Grzonka,
• Aleksandra Krajewska,
• Aleksandra Przewłoka,
• Wawrzyniec Kaszub,
• Zbigniew R. Zytkiewicz,
• Marta Sobanska,
• Maria Kamińska,
• Andrzej Wysmołek and
• Aneta Drabińska

Beilstein J. Nanotechnol. 2021, 12, 566–577, doi:10.3762/bjnano.12.47

• and adjacent layers should be studied. It is well established already that graphene grown on silicon carbide is less strained on substrate terraces than on terrace edges, while electron concentration on the edges is lower than that on terraces [4]. This example shows that fluctuations of substrate

• , such as strain induced by mechanical contact between materials or gating of graphene by neighbouring layers, are important for further applications. Furthermore, electron scattering on defects modifies graphene properties in several ways, for example, additional scattering centres reduce carrier

• analysis of graphene G and 2D band parameters provides information about the number of graphene layers, strain, and carrier concentration [11][12][13][14][15]. Furthermore, in defected graphene, D and D’ defect bands are also observed and their intensity values are related to the concentration of defects

Local stiffness and work function variations of hexagonal boron nitride on Cu(111)

• Abhishek Grewal,
• Yuqi Wang,
• Matthias Münks,
• Klaus Kern and
• Markus Ternes

Beilstein J. Nanotechnol. 2021, 12, 559–565, doi:10.3762/bjnano.12.46

• -BN/Cu(111) substrate. Keywords: decoupling layers; hexagonal boron nitride; local stiffness; Moiré superstructure; work function variation; Introduction Two-dimensional hexagonal boron nitride (h-BN) is among the list of materials that garnered tremendous interest following the exfoliation of mono

• ) [19][20], strain-induced highly corrugated layers for h-BN/Rh(111) [21][22][23], and template layers for molecules with strong local variations of the work function for h-BN/Ir(111) [24] are representative of such morphological diversity. We use low-temperature combined scanning tunnelling (STM) and