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

• 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

• free electrons than semiconductors. In this study there is not enough experimental evidence to conclude that the Smoluchowski effect is responsible for the observed effect; further experiments or theoretical investigations such as DFT calculations would be required. In addition to the Smoluchowski-like

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

• 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

• plausible explanation and more careful study of this tendency is undertaken by means of DFT calculations vide infra. The tubular morphology of the SrxLa1−xS–TaS2 sample with 10 atom % Sr in the precursor was further confirmed by high-angle annular dark field (HAADF)-STEM analysis as shown in Figure 3 (top

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

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

• (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

• is improved by using 1T'-MoS2 as additive in the cathodes [33][34][35][36][37]. Conclusion In conclusion, the anchoring effects of 2H-MoS2 and 1T'-MoS2 monolayers for Li–S batteries were investigated by using DFT calculations. It was found that the binding energies of Li2Sx absorbed on the 1T'-MoS2

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

• decisive for the magnetic moment of the adsorbate molecule. Conclusion We have presented a first-principles analysis of the physical properties of six transition-metal porphyrines adsorbed on a Ag(111) surface. Our DFT calculations are based on the exchange–correlation functionals developed for the study

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

• 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

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

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

• 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

• was estimated to be 3.5 Å. Based on this finding, we construct an atomic model of the three flat-lying N2O molecules on Au(111) and optimize it with total-energy DFT calculations. We find that the trimer is stabilized by electrostatic interactions between the N and O atoms of adjacent N2O molecules

• -decorated tip. In order to understand the chemical behavior of the N2O tips and compare them to the CO tips, we carried out DFT calculations of their electrostatic potential and total densities (see Methods for more detail). Figure 3 shows the calculated electrostatic potential (ESP) map for CO and N2O

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

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

• molecule in a cis conformation binds to a silver ion by means of both nitrogen atoms. To confirm that this interaction also occurs in our Ag–SiO2 colloid, we have performed DFT calculations by considering two possible complexes of bpy in a cis conformation, bonded to Ag+ ion or to Ag0 neutral atom. This

• isolated on the metal surface. The validity of the adatom approximation has been widely verified by DFT calculations of many adsorbed molecules and was able to satisfactorily reproduce the corresponding SERS spectra [51][52][53]. The DFT calculated frequencies of the two proposed complexes are shown in

• + = 2.30 Å; C–C' = 1.499 Å), as reported in the literature [54]. Such spectroscopic and structural similarities, as evidenced by DFT calculations, show that the interaction of the molecule with the colloidal silver closely resembles that occurring in the Ag(I)–bpy coordination compound. In fact, it is

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

• 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

• of information on h-DFT accuracy as compared to experiment, details of UPS measurements and NEGF are contained in Supporting Information File 1. Experimental h-DFT material calculations Hybrid-DFT calculations were carried out in real space with a molecular orbital basis set (MO-BS) and both Hartree

• (see Supporting Information File 1). Results and Discussion h-DFT calculations of embedded Si nanocrystals, fundamentals of energy offset For evaluating the energy shift ΔE of the electronic DOS between usn-Si covered with SiO2 or Si3N4, we calculated two Si-NCs (Si10, 0.8 nm size) within one

• Si3N4 is 0.81 eV which clearly confirms our h-DFT calculations. For the 2.6 nm NWell embedded in Si3N4 we obtain a Eion of 0.06 eV below the value of bulk Si (Figure 5b). The ICT may thus overcompensate quantum confinement and induce a negative ΔEion to bulk Si. The ICT impact length on Si-NWells can be

Lead-free hybrid perovskites for photovoltaics

• Oleksandr Stroyuk

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

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

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

• mechanically bending the monolayer SnSe2(1−x)S2x [56]. Conclusion In conclusion, the electronic properties and catalytic behaviour for HER of SnSe2(1−x)S2x monolayers were investigated using DFT calculations. The band gap of the SnSe2(1−x)S2x monolayer can be continuously tuned from 0.8 eV for SnSe2 to 1.59 eV

Absence of free carriers in silicon nanocrystals grown from phosphorus- and boron-doped silicon-rich oxide and oxynitride

• Daniel Hiller,
• Julian López-Vidrier,
• Keita Nomoto,
• Michael Wahl,
• Wolfgang Bock,
• Tomáš Chlouba,
• František Trojánek,
• Sebastian Gutsch,
• Margit Zacharias,
• Dirk König,
• Petr Malý and
• Michael Kopnarski

Beilstein J. Nanotechnol. 2018, 9, 1501–1511, doi:10.3762/bjnano.9.141

• -atoms for samples with 0.6–0.7 atom % P. It appears more consistent with the available data that P-induced defects (e.g., from interstitial P in the Si NCs or SiOx:P-related states at the surface) cause the PL quenching, as supported by density functional theory (DFT) calculations [29][41]. In that

Chemistry for electron-induced nanofabrication

• Petra Swiderek,
• Hubertus Marbach and
• Cornelis W. Hagen

Beilstein J. Nanotechnol. 2018, 9, 1317–1320, doi:10.3762/bjnano.9.124

• that includes multilayer precursor coverage to describe FEBID processes at lower temperatures or with less volatile precursors [30]. Using density functional theory (DFT) calculations, new light was also shed on an experimentally well investigated precursor, namely (CH3–C5H4)Pt(CH3)3. The interaction

An implementation of spin–orbit coupling for band structure calculations with Gaussian basis sets: Two-dimensional topological crystals of Sb and Bi

• Sahar Pakdel,
• Mahdi Pourfath and
• J. J. Palacios

Beilstein J. Nanotechnol. 2018, 9, 1015–1023, doi:10.3762/bjnano.9.94

• present an implementation of SOC for DFT calculations based on Gaussian-type localized basis sets, attempting to bridge the gap between the simplicity of TB Hamiltonians with their one-parameter implementation of SOC and the accuracy and transferability of a DFT-level description of the band structure. We

• ), using the final parameter value of 120, is the same bands zoomed in near the Γ point showing the similarity of the inverted bands compared to the VASP result. Acknowledgements We thank W. S. Paz for help with the DFT calculations. J.J.P. acknowledges MINECO (Spain) for financial support under grant

Electro-optical interfacial effects on a graphene/π-conjugated organic semiconductor hybrid system

• Karolline A. S. Araujo,
• Luiz A. Cury,
• Matheus J. S. Matos,
• Thales F. D. Fernandes,
• Luiz G. Cançado and
• Bernardo R. A. Neves

Beilstein J. Nanotechnol. 2018, 9, 963–974, doi:10.3762/bjnano.9.90

• surface potential changes on the hybrid system. In summary, interface-induced organized structures atop 2D materials may have an important impact on both design and operation of π-conjugated nanomaterial-based hybrid systems. Keywords: DFT calculations; graphene; organic semiconductors; scanning probe

Dynamics and fragmentation mechanism of (C₅H₄CH₃)Pt(CH₃)₃ on SiO₂ surfaces

• Kaliappan Muthukumar,
• Harald O. Jeschke and
• Roser Valentí

Beilstein J. Nanotechnol. 2018, 9, 711–720, doi:10.3762/bjnano.9.66

• fully and partially hydroxylated SiO2 surfaces. We focus on explaining the initial reactions and the possible fragmentation pathways of the (C5H4CH3)Pt(CH3)3 molecule on the SiO2 surface, and we explain the nature of organic contamination in the deposits. Computational Details DFT calculations for the

Gas-sensing behaviour of ZnO/diamond nanostructures

• Marina Davydova,
• Alexandr Laposa,
• Jiri Smarhak,
• Alexander Kromka,
• Neda Neykova,
• Josef Nahlik,
• Jiri Kroutil,
• Jan Drahokoupil and
• Jan Voves

Beilstein J. Nanotechnol. 2018, 9, 22–29, doi:10.3762/bjnano.9.4

• hybrid ZnO NRs/NCD sensor showed a remarkably enhanced NO2 response compared to the ZnO NRs sensor. Further, inspired by this special hybrid structure, the simulation of interaction between the gas molecules (NO2 and CO2) and hybrid ZnO NRs/NCD sensor was studied using DFT calculations. Keywords

• hybrid ZnO NRs/NCD sensor is carried out using density functional theory (DFT) calculations. Experimental Three different sensor designs were utilized with width and spacing of Au/Ti metal interdigital electrode (IDE) arrays of 100 μm. A schematic illustration of the sensor platforms is shown in Figure 1

• of the interaction between NO2 or CO2 molecules and the hybrid ZnO NRs/NCD sensor were carried out doing first principle DFT calculations with the QuantumWise Atomistix ToolKit simulation package [36][37][38]. The DFT calculations were performed using the local density approximation (LDA) with the

The rational design of a Au(I) precursor for focused electron beam induced deposition

• Ali Marashdeh,
• Thiadrik Tiesma,
• Niels J. C. van Velzen,
• Sjoerd Harder,
• Remco W. A. Havenith,
• Jeff T. M. De Hosson and
• Willem F. van Dorp

Beilstein J. Nanotechnol. 2017, 8, 2753–2765, doi:10.3762/bjnano.8.274

• Al signal and the ring structure come from the supporting Al stub. DFT calculations on isolated molecules Figure 6 and Figure 7 show that ClAuCO is unstable in vacuum, decomposing rapidly to AuCl, while ClAuPMe3 and MeAuPMe3 are stable. To understand why the stability of these compounds varies so

• enough to be used as a precursor for chemical vapor or electron-induced deposition [12][51][52]. Concluding, the DFT calculations of the ground states of isolated molecules help to explain the stability of ClAuPF3, CF3AuCO and ClAuPMe3. MeAuPMe3 appears to be stabilized by a significant activation

• , the SEM analysis, the DFT calculations and the XRD measurements, we now understand the stability and volatility of Au(I) complexes at the molecular level. Regarding ClAuCO, DFT calculations on isolated molecules show that they are stabilized by at least +25.5 kcal/mol. On the other hand, periodic DFT