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

• characterized with NMR (1H, 13C) and electro-spray ionisation mass spectroscopy (ESIMS) the results of which can be found in Supporting Information File 1 (Figures S1–S4). Several methods were used to investigate the properties of the ligands in the absence of the perovskite as reference. DFT calculations were

• Information File 1, Figure S18. DOI for dissolved functionalized 3D particles and free ligands in MeOD. 1H NMR spectra can be seen in the Supporting Information File 1, Figure S21. Supporting Information NMR, ESIMS, UV–vis (kinetic) and PESA measurements, and DFT calculations of the free ligands; UV–vis

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

• the symmetric Ti2O3 model based on DFT calculations [24]. These two structural models have been widely accepted. Mochizuki et al. reported total reflection high-energy positron diffraction results for the (1 × 2) surface, which supported the asymmetric Ti2O3 model [25]. In contrast, our previous study

• DFT and STM and to investigate the bias dependence of simultaneous NC-AFM and STM images. This will be discussed elsewhere since the main subject of this article is the periodic line structure on the rutile TiO2(110)-(1 × 2) reconstructed surface. Our NC-AFM and STM imaging in the same area identified

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

• density functional theory (DFT) study of the adsorption of small Cun (n = 1–4) structures on 2D MoS2 as a model system. We find on a perfect MoS2 monolayer that a single Cu atom prefers an adsorption site above the Mo atom. With increasing nanocluster size the nanocluster binds more strongly when Cu atoms

• character of Cu nanoclusters is preserved. Keywords: copper (Cu); density functional theory (DFT); 2D materials; molybdenum disulfide (MoS2); thin film nucleation; Introduction Since the successful exfoliation of monolayers of graphene by Novoselov et al., 2D materials have gained a large interest in a

• out with density functional theory (DFT) using the Vienna ab initio simulation package (VASP) version 5.4 [34]. It uses 3D periodic boundary conditions and the spin-polarized generalized gradient approximation (GGA) using the Perdew–Burke–Ernzerhof (PBE) approximation to the exchange–correlation

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

• be correlated with the ORR activity [17][18][19][20][21], is only slightly lower for nitriding at 1000 °C compared to nitriding at 700 °C. Hence, none of these different nitrogen configurations can simply explain the trend in the ORR activity. This agrees with the results of DFT-based calculations of

Air oxidation of sulfur mustard gas simulants using a pyrene-based metal–organic framework photocatalyst

• Ghada Ayoub,
• Mihails Arhangelskis,
• Xuan Zhang,
• Florencia Son,
• Timur Islamoglu,
• Tomislav Friščić and
• Omar K. Farha

Beilstein J. Nanotechnol. 2019, 10, 2422–2427, doi:10.3762/bjnano.10.232

• –Teller (BET) surface area of 1325 m2/g (Figure S4, Supporting Information File 1) [44]. The pore size analysis using DFT model revealed pores of approximately 11 Å, which is suitable for diffusion of CEES molecules into the pores of NU-400. The solid-state UV–vis spectrum of NU-400 reveals that the

Improvement of the thermoelectric properties of a MoO₃ monolayer through oxygen vacancies

• Wenwen Zheng,
• Wei Cao,
• Ziyu Wang,
• Huixiong Deng,
• Jing Shi and
• Rui Xiong

Beilstein J. Nanotechnol. 2019, 10, 2031–2038, doi:10.3762/bjnano.10.199

• -principles calculations. The calculations of the electrical properties of the MoO3 monolayer are performed using density functional theory (DFT) as implemented in the Vienna ab initio simulation package (VASP) code [18][19]. We utilize the generalized gradient approximation (GGA) of the Perdew–Burke

First principles modeling of pure black phosphorus devices under pressure

• Ximing Rong,
• Zhizhou Yu,
• Zewen Wu,
• Junjun Li,
• Bin Wang and
• Yin Wang

Beilstein J. Nanotechnol. 2019, 10, 1943–1951, doi:10.3762/bjnano.10.190

• investigate the quantum transport of pure BP devices within the framework of combination of non-equilibrium Green’s function (NEGF) and density functional theory (DFT) [33][34]. The manuscript is organized as follows: In section “Simulation Details”, we show the pure zigzag and armchair BP nanodevices and

• the size of the largest structures with a pressure region of 24L is already compatible with the practical scale of a transistor. In our investigation, two different DFT codes, VASP [35][36] and NanoDCal [33][34], were used to model the electric behavior and quantum transport of the BP devices under

• direction, and 2.102 Å in the vertical direction between two non-equivalent P atomic layers, which is in good agreement with the recognized DFT results [32]. The quantum transport properties of BP devices were implemented by the transport package NanoDCal, which is based on the standard NEGF-DFT method [33

Charge-transfer interactions between fullerenes and a mesoporous tetrathiafulvalene-based metal–organic framework

• Manuel Souto,
• Joaquín Calbo,
• Samuel Mañas-Valero,
• Aron Walsh and
• Guillermo Mínguez Espallargas

Beilstein J. Nanotechnol. 2019, 10, 1883–1893, doi:10.3762/bjnano.10.183

• electron-donor TTF ligand is studied in detail by means of different spectroscopic techniques and density functional theory (DFT) calculations. Importantly, gas sorption measurements demonstrate that sorption capacity is maintained after encapsulation of fullerenes, whereas the electrical conductivity is

• , respectively). Theoretical calculations In order to get further insight into the donor–acceptor interactions between C60 and the TTF-based MOF, theoretical calculations were performed under the density functional theory (DFT). The MUV-2 framework was modelled as previously described [53], with a high-spin Fe

• (2.5 Å, Figure 5). Analysis of the NCI index allows for the visualization of the noncovalent interactions between the TTFTB ligand and the C60 guest, showing a significantly larger NCI surface for conformer B compared to conformer A (Figure 5b). Accurate hybrid DFT molecular calculations including

Long-term entrapment and temperature-controlled-release of SF₆ gas in metal–organic frameworks (MOFs)

• Hana Bunzen,
• Andreas Kalytta-Mewes,
• Leo van Wüllen and
• Dirk Volkmer

Beilstein J. Nanotechnol. 2019, 10, 1851–1859, doi:10.3762/bjnano.10.180

• temperature-modulated thermogravimetric analysis. In order to obtain more realistic energy values, constrained geometry plane wave DFT+D calculations were performed for four different configurations (“min”, “TS”, “centre” and “start/end”) as marked in Figure 5a. For this, the starting configurations were

• extracted from the previous force field scan trajectory and all atomic positions were allowed to relax during subsequent optimization steps, except for the position of the sulfur atom of SF6, which was fixed at the corresponding c/N coordinate of the transition path. The PW-DFT+D calculations were performed

• with the CASTEP code [37] employing the PBE functional [38] and on-the-fly generated ultrasoft pseudopotentials (energy cutoff: 570 eV). Two different correction methods were included in all DFT calculations in order to account for dispersion interactions. The total energy values of these are shown in

Giant magnetoresistance ratio in a current-perpendicular-to-plane spin valve based on an inverse Heusler alloy Ti₂NiAl

• Yu Feng,
• Zhou Cui,
• Bo Wu,
• Jianwei Li,
• Hongkuan Yuan and
• Hong Chen

Beilstein J. Nanotechnol. 2019, 10, 1658–1665, doi:10.3762/bjnano.10.161

• utilizing a density functional theory (DFT)-based Vienna ab-initio simulation package (VASP) [31][32]. Ti (3d24s2), Ni (3d84s2), Al (3s23p1) and Ag (4d105s1) were chosen to be the valence electron configurations. The exchange-correlation interaction is described by the Perdew–Burke–Ernzerhof (PBE

Kelvin probe force microscopy work function characterization of transition metal oxide crystals under ongoing reduction and oxidation

• Dominik Wrana,
• Karol Cieślik,
• Wojciech Belza,
• Christian Rodenbücher,
• Krzysztof Szot and
• Franciszek Krok

Beilstein J. Nanotechnol. 2019, 10, 1596–1607, doi:10.3762/bjnano.10.155

• recently proved to be a Ti-enriched layer on TiO2-terminated SrTiO3(100) [30][40]. The electronic structures of both terminations are much different – the DFT calculated work function values are 1.92 eV and 4.48 eV for SrO and TiO2, respectively [14], obtained for the pure surfaces without vacancies. In

• one terrace may be expected, which can contribute to the observed small decrease in the WF near the step edges. In terms of the absolute work function of TiO2-terminated SrTiO3(100), the obtained value of 3.12(18) eV, averaged across a number of images, is close to this postulated by DFT (3.39 eV) for

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