BiOCl/TiO₂/diatomite composites with enhanced visible-light photocatalytic activity for the degradation of rhodamine B

• Minlin Ao,
• Kun Liu,
• Xuekun Tang,
• Zishun Li,
• Qian Peng and
• Jing Huang

Beilstein J. Nanotechnol. 2019, 10, 1412–1422, doi:10.3762/bjnano.10.139

• and pore volume are shown in Table 1. Density functional theory (DFT) mode was undertaken to characterize the porosity of these samples. According to the N2 adsorption–desorption isotherms, we can see that all four samples belong to IV-type isotherms. BiOCl has an H2-type hysteresis loop, while

Imaging the surface potential at the steps on the rutile TiO₂(110) surface by Kelvin probe force microscopy

• Masato Miyazaki,
• Huan Fei Wen,
• Quanzhen Zhang,
• Yuuki Adachi,
• Jan Brndiar,
• Ivan Štich,
• Yan Jun Li and
• Yasuhiro Sugawara

Beilstein J. Nanotechnol. 2019, 10, 1228–1236, doi:10.3762/bjnano.10.122

• steps running along the [001], , and directions were observed [32][33][34][35], as shown in Figure 1. Density functional theory (DFT) calculations have provided the step configurations and their relative stabilities [36][37][38]. The steps have two types of structures: steps terminated with bridging

• in CPD and propose a simple model for interpreting the local surface potential at the steps with the help of surface charge redistribution, in analogy to the Smoluchowski effect, and the local dipole moment of surface atoms supported by the DFT simulation. Experimental The experiments were carried

• the measurement of the surface potential in KPFM is expected to be smaller than that of the electrostatic potential of atomic species at the step edges. To clarify the influence of the orbit splitting for CPD, insights from DFT calculations are necessary. Comparison between <001> and <1−11> steps For

Playing with covalent triazine framework tiles for improved CO₂ adsorption properties and catalytic performance

• Giulia Tuci,
• Andree Iemhoff,
• Housseinou Ba,
• Lapo Luconi,
• Andrea Rossin,
• Vasiliki Papaefthimiou,
• Regina Palkovits,
• Jens Artz,
• Cuong Pham-Huu and
• Giuliano Giambastiani

Beilstein J. Nanotechnol. 2019, 10, 1217–1227, doi:10.3762/bjnano.10.121

• calculated via Micro-Active (version 1.01) using the density functional theory (DFT) N2 model for slit geometry at optimal goodness of fit vs regularization (0.01) values for both RMS error of fit and roughness of distribution. The cumulative pore volume at the pore width of 2 nm was used to determine the

Pure and mixed ordered monolayers of tetracyano-2,6-naphthoquinodimethane and hexathiapentacene on the Ag(100) surface

• Robert Harbers,
• Timo Heepenstrick,
• Dmitrii F. Perepichka and
• Moritz Sokolowski

Beilstein J. Nanotechnol. 2019, 10, 1188–1199, doi:10.3762/bjnano.10.118

• ) surface that we will report below with that in the crystal. HTPEN is a moderate electron donor with ca. 1 eV larger ionization potential (IP) than TTT [19]. Our own DFT calculations based on the B3-LYP functional predict the HOMO at −5.38 eV and −4.39 eV for HTPEN and TTT, respectively (the latter being

Synthesis and characterization of quaternary La(Sr)S–TaS₂ misfit-layered nanotubes

• Marco Serra,
• Erumpukuthickal Ashokkumar Anumol,
• Dalit Stolovas,
• Iddo Pinkas,
• Ernesto Joselevich,
• Reshef Tenne,
• Andrey Enyashin and
• Francis Leonard Deepak

Beilstein J. Nanotechnol. 2019, 10, 1112–1124, doi:10.3762/bjnano.10.111

• spectroscopy. Density functional theory calculations were carried out to support the experimental observations. Keywords: aberration-corrected STEM; DFT; misfit-layered compounds; nanotubes; Raman spectroscopy; Introduction Since their discovery in 1992 [1], inorganic nanotubes (INTs) have attracted the

• Sr content was undertaken. In particular, high-resolution transmission electron microscopy and Raman spectroscopy served as the main experimental tools to analyze these new nanotubes. Density functional theory (DFT) calculations were used to study the chemical bonding and the stability of the SrxLa1

• open electrode front-illuminated CCD camera cooled to −60 °C (Syncerity, HORIBA, USA). The system utilizes an open confocal microscope (Olympus BXFM) with a spatial resolution better than 1 μm. The measurements were done with the laser beam focused on a single nanotube at a time. DFT calculations All

Electronic and magnetic properties of doped black phosphorene with concentration dependence

• Ke Wang,
• Hai Wang,
• Min Zhang,
• Yan Liu and
• Wei Zhao

Beilstein J. Nanotechnol. 2019, 10, 993–1001, doi:10.3762/bjnano.10.100

• different impurity concentrations are marked by olive, gold, orange and blue dashed squares. We used the deviation of d1 and d2 between pristine phosphorene and doped phosphorene to describe the deformation induced by doping. Calculation method All density function theory (DFT) calculations using first

Electronic properties of several two dimensional halides from ab initio calculations

• Mohamed Barhoumi,
• Ali Abboud,
• Lamjed Debbichi,
• Moncef Said,
• Torbjörn Björkman,
• Dario Rocca and
• Sébastien Lebègue

Beilstein J. Nanotechnol. 2019, 10, 823–832, doi:10.3762/bjnano.10.82

• with density functional theory (DFT) [27] were conducted to study the physical and chemical properties of bulk BiOX compounds as a complement to experiments [28]. In 2006, Zhang et al. [17] calculated the electronic structure of bulk BiOCl with the tight-binding linear muffin-tin orbital (TB-LMTO) code

• and the local density approximation. Bell and Dines [29] reported the results of DFT studies on the geometries and vibrational spectra of several chromium oxo-anions and bulk oxyhalides. Ruckamp et al. [21] reported on the magnetic, thermodynamic and optical properties of the quasi one-dimensional

• , In, La), the chlorides (XOCl and X′FCl with X = Ac, Al; X′ = Ba, Bi), and the iodides (XOI with X = Bi, La, Sc, Y). Computational Details Our present investigation of the electronic properties of the 2D halides employs density functional theory (DFT) as implemented in the Vienna ab initio simulation

Trapping polysulfide on two-dimensional molybdenum disulfide for Li–S batteries through phase selection with optimized binding

• Sha Dong,
• Xiaoli Sun and
• Zhiguo Wang

Beilstein J. Nanotechnol. 2019, 10, 774–780, doi:10.3762/bjnano.10.77

• greatly improved the performance of Li–S batteries [22]. MoS2 has been used as anchoring material for LPSs to enhance the performance of Li–S batteries, when it is embedded into a sulfur-rich matrix cathode [23]. However, density functional theory (DFT) calculations showed that the LPSs are weakly bound

• understood. In this study, we systematically investigated the adsorption of LPSs on 2H-MoS2 and 1T'-MoS2 monolayers with DFT calculation. Our results show that the 1T'-MoS2 monolayer interacts strongly with Li2Sx, which will hinder the shuttle effect. Taking into account the better conductivity, 1T'-MoS2

• (CBM) and valence band maximum (VBM) are located at the K point, which is consistent with previous DFT calculations [39]. 1T'-MoS2 is a narrow-bandgap semiconductor with a bandgap of 0.15 eV. Various intermediates, Li2Sx (x = 1–8), of LPSs were observed in Li–S batteries [40]. The optimized atomic

The effect of translation on the binding energy for transition-metal porphyrines adsorbed on Ag(111) surface

• Luiza Buimaga-Iarinca and
• Cristian Morari

Beilstein J. Nanotechnol. 2019, 10, 706–717, doi:10.3762/bjnano.10.70

• are detailed here as resulted from DFT calculations. Van der Waals interactions as well as the strong correlation in 3d orbitals of transition metals were taken into account in all calculations, including the structural relaxation. For each system we investigate four relative positions of the metallic

• molecule–surface charge transfer, analyzed for different geometric configurations allows us to propose qualitative models, relevant for the understanding of the self-assembly processes and related phenomena. Keywords: Ag(111) surface; DFT+U; metal porphyrine; van der Waals; Introduction Metalloporphyrins

• . Such modifications of the electronic structure are of great interest for all potential applications. Theoretical assessment of the adsorption mechanism of TMPP on silver in the framework of DFT ask for an accurate estimation of the van der Waals dispersive interactions, which are expected to be

A carrier velocity model for electrical detection of gas molecules

• Ali Hosseingholi Pourasl,
• Sharifah Hafizah Syed Ariffin,
• Mohammad Taghi Ahmadi,
• Razali Ismail and
• Niayesh Gharaei

Beilstein J. Nanotechnol. 2019, 10, 644–653, doi:10.3762/bjnano.10.64

• Atomistix Toolkit (ATK) is performed, which is based on density functional theory (DFT) and non-equilibrium Green's function formalism. The physical properties of the GNRs are dependent on the width and edge shape of the ribbons. Figure 3 illustrates the schematic of a field effect transistor using an 8

• between the adsorbate and AGNR by introducing the hopping integral parameter (t′), was formulated. Then, the molecular adsorption effect on the carrier velocity was investigated in the form of current–voltage properties. The DFT calculations study was performed to further investigate gas molecule

Quantification and coupling of the electromagnetic and chemical contributions in surface-enhanced Raman scattering

• Yarong Su,
• Yuanzhen Shi,
• Ping Wang,
• Jinglei Du,
• Markus B. Raschke and
• Lin Pang

Beilstein J. Nanotechnol. 2019, 10, 549–556, doi:10.3762/bjnano.10.56

• ]. Only the ω3 mode is thought to be sensitive to charge redistribution due to the nuclear motion of the S-atom with respect to metal substrate and phenyl ring [15]. DFT calculations (Gaussian 09 package) were performed based on benzenethiol bound to three silver atom clusters, for illustration, and the

Mo-doped boron nitride monolayer as a promising single-atom electrocatalyst for CO₂ conversion

• Qianyi Cui,
• Gangqiang Qin,
• Weihua Wang,
• Lixiang Sun,
• Aijun Du and
• Qiao Sun

Beilstein J. Nanotechnol. 2019, 10, 540–548, doi:10.3762/bjnano.10.55

• ), including Sc to Zn, Mo, Ru, Rh, Pd and Ag, supported on a boron nitride (BN) monolayer with boron vacancies, were investigated as electrocatalysts for the CO2 reduction reaction (CRR) using comprehensive density functional theory (DFT) calculations. The results demonstrate that a single-Mo-atom-doped boron

• (TM = Sc to Zn, Mo, Rh, Ru, Pd and Ag) anchored on the boron vacancy in a BN monolayer as electrocatalysts for CO2 conversion through comprehensive density functional theory (DFT) calculations. Based on the calculated results, single Mo doped onto a BN (Mo-doped BN) monolayer was selected as the

• was chosen as the SAC for the further investigation. CO2 electrocatalytic reduction The reaction mechanism of Mo-doped BN monolayer as a SAC for CRR was investigated via DFT calculations. The profile of the Gibbs free energy of the possible intermediates at each hydrogenation step is shown in Figure 3

Temperature-dependent Raman spectroscopy and sensor applications of PtSe₂ nanosheets synthesized by wet chemistry

• Mahendra S. Pawar and
• Dattatray J. Late

Beilstein J. Nanotechnol. 2019, 10, 467–474, doi:10.3762/bjnano.10.46

• date due to difficulties in synthesis. It is well known that bulk PtSe2 is a semimetal in nature with a nearly zero band gap [18][19]. With the help of theoretical calculations such as density functional theory (DFT) and local-density approximations (LDAs), it has been observed that bulk PtSe2 shows a

Sub-wavelength waveguide properties of 1D and surface-functionalized SnO₂ nanostructures of various morphologies

• Venkataramana Bonu,
• Binaya Kumar Sahu,
• Arindam Das,
• Sankarakumar Amirthapandian,
• Sandip Dhara and
• Harish C. Barshilia

Beilstein J. Nanotechnol. 2019, 10, 379–388, doi:10.3762/bjnano.10.37

• 2.6 eV are assigned to band edge transitions. Earlier, it was shown from DFT calculations using an all-electron Gaussian approximation that formation of an acceptor state close to 1 eV above the valence band occurs due to the stable oxygen vacancies [31]. Thus, the above mentioned studies point out

• that the observed PL peaks at 1.84, 1.97, 2.1, 2.3, and 2.5 eV are seen as a result of transitions from shallow donor (SD) levels to acceptor level (Figure 8d). The peak at 2.75 eV is assigned to the band edge transition (Figure 8d). DFT calculations using the generalized gradient approximation (GGA

Intuitive human interface to a scanning tunnelling microscope: observation of parity oscillations for a single atomic chain

• Sumit Tewari,
• Jacob Bakermans,
• Christian Wagner,
• Federica Galli and
• Jan M. van Ruitenbeek

Beilstein J. Nanotechnol. 2019, 10, 337–348, doi:10.3762/bjnano.10.33

• feedback loop from the experimental conductance values, a real-time conductance estimation based on the atomistic positions given by the MD simulations could be useful. Tight-binding models have been known [56] to give a relatively fast (as compared to DFT and other computationally expensive methods

Nitrous oxide as an effective AFM tip functionalization: a comparative study

• Taras Chutora,
• Bruno de la Torre,
• Pingo Mutombo,
• Jack Hellerstedt,
• Jaromír Kopeček,
• Pavel Jelínek and
• Martin Švec

Beilstein J. Nanotechnol. 2019, 10, 315–321, doi:10.3762/bjnano.10.30

• characterize the adsorption of the N2O species on Au(111) by means of atomic force microscopy with CO-functionalized tips and density functional theory (DFT) simulations. Subsequently we devise a method of attaching a single N2O to a metal tip apex and benchmark its high-resolution imaging and spectroscopic

• capabilities using FePc molecules. Our results demonstrate the feasibility of high-resolution imaging. However, we find an inherent asymmetry of the N2O probe-particle adsorption on the tip apex, in contrast to a CO tip reference. These findings are consistent with DFT calculations of the N2O- and CO tip

• ), which revealed elongated structures; we attribute these to individual flat-lying N2O molecules. In a cluster, typically composed of 5–25 molecules, the N2O molecules have a preferential short-range arrangement of rotationally symmetrical trimers, with intermolecular distances of about 4.3 Å. A DFT

Au–Si plasmonic platforms: synthesis, structure and FDTD simulations

• Anna Gapska,
• Marcin Łapiński,
• Paweł Syty,
• Wojciech Sadowski,
• Józef E. Sienkiewicz and
• Barbara Kościelska

Beilstein J. Nanotechnol. 2018, 9, 2599–2608, doi:10.3762/bjnano.9.241

• domain (FDTD) method. The method allows one to find the spatial distributions of all components of an electromagnetic field propagating through the investigated system, at selected time intervals. Applying in the next step the discrete Fourier transform (DFT) leads to a change from the time domain to the

• Fourier transform (DFT) analysis, allowed for obtaining the absorbance of the sample in the frequency domain. To switch from the time domain to the frequency domain, FDTD simulations and subsequent discrete Fourier transform were performed. This will be called FDTD/DFT further in the text. The same result

• components parallel to the surface are much stronger than those of the perpendicular y-components. This effect is particularly clearly visible for the magnetic field. The calculated absorbance as a result of the FDTD/DFT simulation is shown in Figure 15. We can observe a quite good agreement with the

Improved catalytic combustion of methane using CuO nanobelts with predominantly (001) surfaces

• Qingquan Kong,
• Yichun Yin,
• Bing Xue,
• Yonggang Jin,
• Wei Feng,
• Zhi-Gang Chen,
• Shi Su and
• Chenghua Sun

Beilstein J. Nanotechnol. 2018, 9, 2526–2532, doi:10.3762/bjnano.9.235

• (Hiden MS HPR20) with a secondary electron multiplier detector. Methane conversion was defined as: (influent concentration of CH4 − effluent concentration of CH4)/influent concentration of CH4 × 100%. Theoretical calculations Spin-polarized DFT calculations were performed under the generalized gradient

• DFT-D3 method, as developed by Grimme and Jónsson [32][33]. The CuO surfaces were modelled by 2 × 2 supercells, shown as slabs with thicknesses in the range of 10–14 Å, depending on the surface orientation, and a vacuum space of 12 Å was applied over the surface. The transition state (TS) was

SERS active Ag–SiO₂ nanoparticles obtained by laser ablation of silver in colloidal silica

• Cristina Gellini,
• Francesco Muniz-Miranda,
• Alfonso Pedone and
• Maurizio Muniz-Miranda

Beilstein J. Nanotechnol. 2018, 9, 2396–2404, doi:10.3762/bjnano.9.224

• computational DFT approach provided evidence of ligand adsorption on positively charged adatoms of the silver nanostructured surface, in a very similar way to the metal/molecule interaction occurring in the corresponding Ag(I) coordination compound. Keywords: 2,2’-bipyridine; DFT; laser ablation; silica

• and transmission electron microscopy (TEM). The SERS efficiency was tested by adsorption of 2,2'-bipyridine as a molecular reporter, whose SERS spectrum was interpreted by DFT, in order to gain information on the adsorbate and the interaction of the molecule with the metal surface. To our knowledge

• 09 package [24]. Optimized geometries were obtained at the DFT level of theory with the Becke 3-parameter hybrid exchange functional combined with the Lee–Yang–Parr correlation functional B3LYP [25][26], along a mixed basis set made up of 6-311++G(d,p) for non-metal atoms and Lanl2DZ [27][28][29] for

Surface energy of nanoparticles – influence of particle size and structure

• Dieter Vollath,
• Franz Dieter Fischer and
• David Holec

Beilstein J. Nanotechnol. 2018, 9, 2265–2276, doi:10.3762/bjnano.9.211

• that, except for the hydrogen atom, exact solutions of this equation do not exist. Therefore, a large number of methods for numerical solutions have been developed. Most successful are calculations based on density functional theory (DFT). This kind of modelling has some restrictions, i.e., the

• application of this computational strategy can be found in papers from Medasani et al. [49][58][59]. Figure 16 displays the results for calculations of the surface energy of silver particles [49][58]. (The abbreviation DFT-GGA stands for density functional theory using a generalized gradient approximation

• correction according to Holec et al. [53]. The calculations by Medasani et al. are based on the assumption of crystallized particles. Looking at the results, it is remarkable that the values for particles with a diameter smaller than 2 nm (obtained by DFT calculations) vary so drastically. Furthermore, it is

Intrinsic ultrasmall nanoscale silicon turns n-/p-type with SiO₂/Si₃N₄-coating

• Dirk König,
• Daniel Hiller,
• Noël Wilck,
• Birger Berghoff,
• Merlin Müller,
• Sangeeta Thakur,
• Giovanni Di Santo,
• Luca Petaccia,
• Joachim Mayer,
• Sean Smith and
• Joachim Knoch

Beilstein J. Nanotechnol. 2018, 9, 2255–2264, doi:10.3762/bjnano.9.210

• Moore’s law to reach the Si-crystallization limit of ca. 1.5 nm [15]. In our present work, we prove by hybrid-density functional theory (h-DFT) simulations and synchrotron-based long-term ultraviolet photoelectron spectroscopy (UPS) that usn-Si indeed can have a massive ΔE of their electronic density of

• states (DOS) when embedded in SiO2 or Si3N4. We use further h-DFT results of a Si-nanowire (NWire) covered in SiO2 and Si3N4 to examine the device behaviour of an undoped Si-NWire FET based solely on CMOS-compatible materials (e.g., Si, SiO2, Si3N4) using the nonequilibrium Green’s function (NEGF

• ) approach. Following an explanation of the theoretical and experimental methods used, we turn to results for Si-NCs obtained from h-DFT. Here, we focus on the electronic structure of Si-NCs as a function of the embedding dielectric and its thickness of up to 3 monolayers (MLs). The latter dependence

Lead-free hybrid perovskites for photovoltaics

• Oleksandr Stroyuk

Beilstein J. Nanotechnol. 2018, 9, 2209–2235, doi:10.3762/bjnano.9.207

• ]. Calculations by the density functional theory (DFT) indicated that a partial substitution of Cs+ with Rb+ should considerably increase the stability of CsSnI3 [117]. To avoid a partial conversion of Sn2+ into Sn4+, the latter acting as charge carrier traps in ASnX3 HPs, it was suggested to deposit the

• PCE of 0.2% for MAGeI3-based cells (Table 1). A DFT study of CsGeI3 HP showed that the iodide vacancy in this material can serve as a deep hole trap, in contrast to the corresponding Pb- and Sn-based HPs resulting in a reduction of the Voc [141]. These results indicate that efforts should be applied

Metal-free catalysis based on nitrogen-doped carbon nanomaterials: a photoelectron spectroscopy point of view

• Mattia Scardamaglia and
• Carla Bittencourt

Beilstein J. Nanotechnol. 2018, 9, 2015–2031, doi:10.3762/bjnano.9.191

• on it due to the higher electronegativity of the N atom [59][60]. Thus, it will attract electrons from the anode more easily and facilitate the ORR. Yu et al. [59] using DFT calculations showed the increase of the density of states at the Fermi level of the C atom neighbor of a N atom. This is due to

• catalyst (Figure 9b). Different groups calculated by using DFT the energy barriers for oxygen molecule adsorption and dissociation on pristine and N-doped graphene depending on the nitrogen configuration [21][60][110][111][112]. Ni and co-workers [111], in particular, found that the energy barrier

• pyridinic and graphitic N, compared to the DFT calculation results (black circles connected by dashed lines). The numbers denote the total concentration of nitrogen (NP + NG). Solid lines demonstrate the hypothetical situation when pyridinic N provides no charge transfer while graphitic N donates one

Improving the catalytic activity for hydrogen evolution of monolayered SnSe_2(1−x)S_2x by mechanical strain

• Sha Dong and
• Zhiguo Wang

Beilstein J. Nanotechnol. 2018, 9, 1820–1827, doi:10.3762/bjnano.9.173

• functional theory (DFT) computations. The results showed SnSe2(1−x)S2x alloys with continuously changing bandgaps from 0.8 eV for SnSe2 to 1.59 eV for SnS2. The band structure of a SnSe2(1−x)S2x monolayer can be further tuned by applied compressive and tensile strain. Moreover, tensile strain provides a

• activity of the SnSe2(1-x)S2x monolayer. Keywords: density functional theory (DFT); electronic properties; hydrogen evolution reaction; mechanical strain; SnSe2(1−x)S2x monolayer; Introduction Hydrogen is a clean energy source with outstanding properties such as high specific energy per mass, easy

• . In this work, the electronic properties and catalytic behaviour for HER of SnSe2(1−x)S2x (x = 0, 0.125, 0.25, 0.375, 0.5, 0.625, 0.750, 0.875 and 1.0) monolayers were investigated by density functional theory (DFT). It was shown that band gap and catalytic activity of these alloys can be continuously

Free-radical gases on two-dimensional transition-metal disulfides (XS₂, X = Mo/W): robust half-metallicity for efficient nitrogen oxide sensors

• Chunmei Zhang,
• Yalong Jiao,
• Fengxian Ma,
• Sri Kasi Matta,
• Steven Bottle and
• Aijun Du

Beilstein J. Nanotechnol. 2018, 9, 1641–1646, doi:10.3762/bjnano.9.156

• , only few possess all necessary properties and many of them are unstable. Therefore, to explore more experimentally feasible and stable half-metallic materials is highly desirable. In this paper, a density functional theory (DFT) study is carried out to show that monolayer XS2 (X = Mo, W) can

• NO, NO2 adsorbed on monolayer XS2 (X = Mo, W) are performed using DFT within generalized gradient approximation (GGA) of the Perdew–Burke–Ernzerhof (PBE) functional, as implemented in the Vienna ab initio simulation package (VASP) [34][35][36]. To study 2D systems under the periodic boundary

• conditions, a vacuum layer with a thickness of more than 20 Å was set to minimize artificial interactions between neighboring layers. A dispersion correction of total energy (DFT-D3 method) [37] is used to incorporate the long-range van der Waals interaction. The structures are fully relaxed until energy and