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

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

• increasing coverage, a few stable single molecules can be found, which are most likely stabilized by surface defects, as well as stable molecular assemblies in limited areas close to terrace edges, where movement is hampered by steric interactions (Figure S2, Supporting Information File 1). The

• assume that the shape asymmetry of SnPc may also appear as a result of the presence of the surrounding molecules, or it can arise from the corrugated nature of the rutile (110) surface including its defects. To confirm the identification of Sn-up and Sn-down geometries, we performed DFT calculations. A

• -range dispersive forces. The fact that the Sn-down geometry is preferred could be rationalized by assuming that the Sn atom locates between surface hydroxy groups, allowing for attractive interactions between positive surface defects and negatively charged pyrrole-like subunits. Such a geometry can

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 electron–phonon interaction, i.e., scattering of electrons from defects. Chakrabarty et al. reported that the linewidth of the A1g peak in single-layer MoS2 that was subsequently used in transistors, broadened due to n-type doping where the phonon linewidth renormalized under the presence of an

• electric filed [18]. Similarly, the Raman linewidths in graphene are found to increase with defects resulting from electron–impurity and electron–phonon scattering [19]. Moreover, the Raman linewidth broadening is also attributed to the confinement of the optical phonons. Specifically, in the case of low

• and bulk WSe2 varies widely in low T, but remains almost constant at high T. This is because the decay in τ is governed by various scattering mechanisms which are caused by the interaction of phonons with defects, boundaries, other phonons, etc. It is important to analyze the scattering as a whole

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

• address the requirements of the application in terms of quantum properties of the defects. This approach is quite difficult as it is based mostly on the reliability of modeling and predicting of color center properties in various materials, and their experimental verification is challenging. In this paper

• complementary outstanding properties compared to the other 3D bulk materials. Keywords: boron nitride; color centers; quantum applications; quantum properties; Review Introduction Point defects (impurity atoms or complex of atoms) in solids are recognized elementary units for various quantum technology

• applications, such as quantum information science [1], quantum sensing [2], quantum cryptography [3], and quantum computing [4][5]. After the discovery and assessment of their quantum properties, some of these defects became prominent examples of material platforms for quantum photonics [6][7][8][9][10] and

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

• images before and after AFM imaging. Additionally, we observe similar ordering in crystal lattices and an absence of defects in the lattice fringes for both figures. These observations suggest that plastic deformation did not occur during AFM experiments. It is also clear that Figure 2a and Figure 2b

• hydrogen- and oxygen-termination, as well as chemical aging of the diamond surface can lead to significant variations in surface energy [63]. Furthermore, a loss of hydrogen termination of the diamond surface could result in CHx defects [64][65] as well C–C dimer surface reconstruction [66]. Therefore, a

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

• less light scattering in the metal interlayer [28][29][30]. The annealing treatment has successfully reduced the number of defects leading light scattering [4][36]. The enhanced structural ordering decreases the electron scattering at grain boundaries and impurities. This can lead to an increase in the

• heat treatment lowers the trade-off between transparency and conductivity by reducing structural defects in the films. The sheet resistance of the multilayer structure of the IAAI film can be expressed as [29]: where is the total sheet resistance of the IAAI film, RAl and RAg are the sheet resistance

Effect of substitutional defects on resonant tunneling diodes based on armchair graphene and boron nitride nanoribbons lateral heterojunctions

• Majid Sanaeepur

Beilstein J. Nanotechnol. 2020, 11, 688–694, doi:10.3762/bjnano.11.56

• substitutional defects (including BC, NC, CB, and CN) at the interface of graphene and boron nitride nanoribbons on the negative differential resistance behavior of the proposed resonant tunneling diode is investigated. Transport simulations are carried out in the framework of tight-binding Hamiltonians and non

• heterojunction; armchair boron nitride nanoribbon (ABNNR); armchair graphene nanoribbon (AGNR); negative differential resistance (NDR); nonequilibrium Green’s function (NEGF); resonant tunneling diode (RTD); substitutional defects; Introduction 2D materials have gained tremendous research interest due to the

• between graphene and hBN [3]. However, inevitable interfacial defects located at the interface of Gr/hBN heterojunctions, including point defects (single vacancies and substitutional defects) and topological defects can alter the electronic properties of Gr/hBN heterostructures and, consequently, the

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

• strain maps reflect homogeneous and dislocation-free STO and LSMO layers, and a BTO layer with several linear defects, most of which are concentrated close to the BTO/LSMO interfaces. Misfit dislocation-free epitaxial growth of LSMO films under (001)-oriented STO substrates is expected and widely

• reported [2][47][48][49][50] due to their small mismatch (≈0.7%); dislocations appear in LSMO under compressive strain [51][52][53], while twin walls are expected under tensile strain [54][55][56] with the thickness-dependent elastic deformations already in LSMO/STO systems [54]. Linear defects in the BTO

Soybean-derived blue photoluminescent carbon dots

• Shanshan Wang,
• Wei Sun,
• Dong-sheng Yang and
• Fuqian Yang

Beilstein J. Nanotechnol. 2020, 11, 606–619, doi:10.3762/bjnano.11.48

• -CDs. Note that the deviation of the QY trend from that of the N-atomic fraction at high N content implies that other factors (i.e., defects) may start to influence the PL response of the LA-CDs-x% with x ≥ 30%. Table 3 summarizes the PL characteristics of the soybean-derived CDs. For comparison, the

Adsorptive removal of bulky dye molecules from water with mesoporous polyaniline-derived carbon

• Hyung Jun An,
• Jong Min Park,
• Nazmul Abedin Khan and
• Sung Hwa Jhung

Beilstein J. Nanotechnol. 2020, 11, 597–605, doi:10.3762/bjnano.11.47

• composed of both graphitic and defect phases. Therefore, KOH-900 might be useful for adsorption because of defects and the graphitic layers (with π-electrons). Dye adsorption over polyaniline-derived carbon (PDC) Firstly, adsorption of AR1 over PDC and AC was carried out for 6 h. As illustrated in Figure

Comparison of fresh and aged lithium iron phosphate cathodes using a tailored electrochemical strain microscopy technique

• Matthias Simolka,
• Hanno Kaess and
• Kaspar Andreas Friedrich

Beilstein J. Nanotechnol. 2020, 11, 583–596, doi:10.3762/bjnano.11.46

• ESM data. The ESM signal, which we observe on carbon-coated LFP, is not only limited to structural boundaries within one single grain, which are known to exhibit a high mobility for ions due to structural disordering, high concentration of defects and lower energy barrier [40][54][55]. We also observe

• signal is produced. The olivine crystal structure on the planar locations is not the only influence on the ionic mobility, but it is an additional factor next to the structural disordering, high concentration of defects and lower energy barrier and more important on planar locations than on structural

Examination of the relationship between viscoelastic properties and the invasion of ovarian cancer cells by atomic force microscopy

• Mengdan Chen,
• Jinshu Zeng,
• Weiwei Ruan,
• Zhenghong Zhang,
• Yuhua Wang,
• Shusen Xie,
• Zhengchao Wang and
• Hongqin Yang

Beilstein J. Nanotechnol. 2020, 11, 568–582, doi:10.3762/bjnano.11.45

• an important factor determining the mechanical properties of cells [50]. Some researchers have shown that alterations in the cytoskeletal structure or functional defects of cells are associated with the ability of tumor cells to proliferate [51]. The actin filaments on the cell membrane can affect

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

• different processes [9]. In two of them, the formation of nanostructures begins with the nucleation of holes and their subsequent growth. Nucleation can be caused by small thermal density fluctuations (homogeneous nucleation) or defects in the metal film or in the interface between the film and the

• responsible for dewetting. Especially because defects are always present in the interface between the substrate and the film. In the design of metallic nanostructure systems for plasmonic applications, the homogeneous distribution of nanostructures is very important, both in size and location on the surface

Interfacial charge transfer processes in 2D and 3D semiconducting hybrid perovskites: azobenzene as photoswitchable ligand

• Nicole Fillafer,
• Tobias Seewald,
• Lukas Schmidt-Mende and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2020, 11, 466–479, doi:10.3762/bjnano.11.38

• virtual level. Usually trap states and lattice defects in the surface region lead to a high concentration of charge carriers and to radiative recombination with a bright luminescence [51][52]. Instead, electrons from the high virtual level can be transferred also to an excited state of the azobenzene

• and AzoOC12), which can be seen in Figure 6B. As many other charge-carrier dynamics beside the radiative recombination, such as photorecycling and surface defects, affect the PL no (bi)exponential fit could be found [53][54]. Thus, the recorded measurements are discussed qualitatively. A small spacing

Atomic-resolution imaging of rutile TiO₂(110)-(1 × 2) reconstructed surface by non-contact atomic force microscopy

• Daiki Katsube,
• Shoki Ojima,
• Eiichi Inami and
• Masayuki Abe

Beilstein J. Nanotechnol. 2020, 11, 443–449, doi:10.3762/bjnano.11.35

• microscopy (STM) [10][11][12], transmission electron microscopy [13][14], and density functional theory (DFT) [15][16][17][18][19]. These studies have determined many surface properties such as structure, local defects, and adsorption sites. The (1 × 1) surface transforms to the (1 × 2) surface by oxygen

• can be clearly seen that the (1 × 2) structure was formed over a wide area (200 × 200 nm2) of the surface. Some local structures such as single links, double links, and line defects, which have been reported in previous studies [22][27][28][32], are evident on the (1 × 2) surface in Figure 2c. These

• -AFM and tunneling current for STM), the surface structure sometimes results in different contrasts in both images. In Figure 3, white squares and circles indicate line defects and protrusions, which are considered to be adsorbates or contamination. A line defect was imaged as a likely vacancy by STM

Electrochemically derived functionalized graphene for bulk production of hydrogen peroxide

• Munaiah Yeddala,
• Pallavi Thakur,
• Anugraha A and
• Tharangattu N. Narayanan

Beilstein J. Nanotechnol. 2020, 11, 432–442, doi:10.3762/bjnano.11.34

• defects along sheet edges are the most active sites for peroxide production in rGO [3]. They also showed that the performance of these rGO-based catalysts in alkaline conditions under low overpotential outperform the existing state-of-the-art catalysts. However, a large extent of oxidation may hamper the

• performance in 0.1 M KOH solution, and the data is given in Figure 5. In Figure 5a, the Raman spectra of EEG before and after 3 h of chronoamperometry are shown, which show no appreciable change in either the peak position or peak intensity. This indicates that no additional defects are created during the

• experiment. The important Raman peaks are marked in the figure and the shoulder peak in “G” is due to the additional single phonon intra-valley scattering process (named as D’) which is due to the presence of defects. However, the FTIR spectrum (see Figure S4b) shows evidence for the formation of OH

Synthesis and enhanced photocatalytic performance of 0D/2D CuO/tourmaline composite photocatalysts

• Changqiang Yu,
• Min Wen,
• Zhen Tong,
• Shuhua Li,
• Yanhong Yin,
• Xianbin Liu,
• Yesheng Li,
• Tongxiang Liang,
• Ziping Wu and
• Dionysios D. Dionysiou

Beilstein J. Nanotechnol. 2020, 11, 407–416, doi:10.3762/bjnano.11.31

• -type CuO semiconductor is ≈1.2 eV [6]. The application of CuO covers the fields of photocatalytic degradation of organic contaminants [7], photocatalytic reduction of CO2 [8][9], photocatalytic splitting of water [10], etc. Nanoscale CuO has been widely studied owing to its increased surface defects

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

• monolayer is presented by Rawal et al. [25] to study the effect of defects in MoS2 on the catalytic activity of the supported nanoparticles. They observe that the magnitude of binding energy and charge transfer follows the trend Cu > Ag > Au. On the pristine surface the binding energies of the nanoparticles

• particular when the monolayer is defect-rich. MoS2 is known to be naturally high in defects [21][32], in particular S vacancies. It has been predicted that S vacancies in a MoS2 monolayer are most stable when they occur in a row, with a decrease in the vacancy formation energy as the number of vacancies

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

• local defects of the flat surface (initially existing or created by the irradiation) initiate the formation of ripple trains [8][25]. If a nanorod is exposed to the irradiation, then the edges between the side facets and the ends can play the role of such surface defects. Our experiment does confirm the

• role of boundary surface defects in ripple formation. In Figure 6c one can see the formation of two to three ordered nanoripples oriented parallel to the end edge. A similar mechanism influences the ripple formation at higher energy and fluences, i.e., when the ripple wavelength becomes larger (Figure

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

• enable entities smaller than these gaps to leave the bloodstream. Secondly, defects of the lymphatic system in tumors prevent these macromolecular therapeutics to be cleared from the tumor, giving them additional time to release their active cargo. This was the first example of targeting tumor tissues

Size effects of graphene nanoplatelets on the properties of high-density polyethylene nanocomposites: morphological, thermal, electrical, and mechanical characterization

• Tuba Evgin,
• Alpaslan Turgut,
• Georges Hamaoui,
• Zdenko Spitalsky,
• Nicolas Horny,
• Matej Micusik,
• Mihai Chirtoc,
• Mehmet Sarikanat and
• Maria Omastova

Beilstein J. Nanotechnol. 2020, 11, 167–179, doi:10.3762/bjnano.11.14

• defects, which can then result in a decreased tensile strength. On the other hand, the filler can reinforce the polymer matrix, and this reinforcing effect becomes more obvious at higher concentrations (≥7 vol %). The nonlinear behavior of the tensile strength is then a consequence of these effects. With

Internalization mechanisms of cell-penetrating peptides

• Ivana Ruseska and
• Andreas Zimmer

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

Simple synthesis of nanosheets of rGO and nitrogenated rGO

• Pallellappa Chithaiah,
• Madhan Mohan Raju,
• Giridhar U. Kulkarni and
• C. N. R. Rao

Beilstein J. Nanotechnol. 2020, 11, 68–75, doi:10.3762/bjnano.11.7

• N-rGO sample (Figure 2b) shows D, G and 2D band at, respectively, at 1354, 1581, and 2843 cm−1. The D-band is associated with the breathing modes of six-membered carbon rings that are activated by defects and structurally disordered, and the G-band originates from in-plane vibrations of sp2