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

• analysis of these substrate effects can be found in [18]. Electrical and electronic properties The majority of defect engineering studies using the HIM have focused on tuning electrical conductivity. First work in this area concentrated on graphene, seeking to locally modulate its 2D electronic structure

• of the HIM, junction barriers of width 1–2 nm were created, that is, narrow enough for the tunneling current to propagate. An overview of the sample and a schematic outlining the irradiation approach are shown in Figure 2d. The electronic properties of the junction barrier can be continuously tuned

Nanoporous and nonporous conjugated donor–acceptor polymer semiconductors for photocatalytic hydrogen production

• Zhao-Qi Sheng,
• Yu-Qin Xing,
• Yan Chen,
• Guang Zhang,
• Shi-Yong Liu and
• Long Chen

Beilstein J. Nanotechnol. 2021, 12, 607–623, doi:10.3762/bjnano.12.50

• Conjugated polymers (CPs) as photocatalysts have evoked substantial interest. Their geometries and physical (e.g., chemical and thermal stability and solubility), optical (e.g., light absorption range), and electronic properties (e.g., charge carrier mobility, redox potential, and exciton binding energy) can

• tunable bandgaps, high charge carrier mobility, and efficient intramolecular charge transfer. In this minireview, recent advances of D–A polymers in photocatalytic hydrogen evolution are summarized with a particular focus on modulating the optical and electronic properties of CPs by varying the acceptor

• ), optical (e.g., light absorption range), and electronic properties (e.g., charge carrier mobility, redox potential and exciton binding energy) can be easily tuned via structural design. In addition, they are of light weight (i.e., mainly composed of C, N, O, and S) [8][9][10]. In 1985, the first CP-based

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

• morphology substantially modify graphene properties. A novel approach of graphene-based nanostructures are van der Waals heterostructures in which graphene is transferred onto another material with a different morphology and electronic properties [5]. However, in those kinds of structures several aspects

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

• well-controlled adsorption and electronic properties [11][12][13][14][15][16][17][18]. In such systems, h-BN shows a rich structural and electronic morphology, which depends on the lattice mismatch and the interaction strength with the substrate: Large and flat lattice-matched terraces for h-BN/Ni(111

• small geometrical corrugation [27]. Further experimental investigations, using both local probes and averaging techniques, revealed more details of the mechanical and electronic properties of the system, but also inconsistent results about the structural corrugation [26][28][29][30]. For example, Brülke

Interface interaction of transition metal phthalocyanines with strontium titanate (100)

• Reimer Karstens,
• Thomas Chassé and
• Heiko Peisert

Beilstein J. Nanotechnol. 2021, 12, 485–496, doi:10.3762/bjnano.12.39

• general chemical structure of the chosen molecules is shown in Figure 1c. The electronic properties of transition metal phthalocyanines (TMPcs) can be widely chemically modified at both the central metal atom and the macrocycle. This chemical tunability allows for a broad variation of electronic

• properties. Hence, TMPcs are well suited for systematic studies of interface properties. The fluorination of TMPcs varies exceptionally the ionization potential (IP), affecting distinctly the interface properties [29][30][31][32]. As recently shown for FePcFx/MoS2 [33], a charge transfer at interfaces might

Spontaneous shape transition of Mn_xGe_1−x islands to long nanowires

• S. Javad Rezvani,
• Luc Favre,
• Gabriele Giuli,
• Yiming Wubulikasimu,
• Isabelle Berbezier,
• Augusto Marcelli,
• Luca Boarino and
• Nicola Pinto

Beilstein J. Nanotechnol. 2021, 12, 366–374, doi:10.3762/bjnano.12.30

• ], electrical [2], and magnetic [3] properties. Low-dimensional materials have unique electronic properties that can be tuned via geometrical or structural modifications [4][5][6][7][8]. Also, the tunability of the spin degrees of freedom in semiconducting materials offers a great potential for future

Extended iron phthalocyanine islands self-assembled on a Ge(001):H surface

• Rafal Zuzak,
• Marek Szymonski and
• Szymon Godlewski

Beilstein J. Nanotechnol. 2021, 12, 232–241, doi:10.3762/bjnano.12.19

• achieve control over the growth of molecular columns of CuPc molecules [40]. Metal phthalocyanines exhibit useful physical, chemical, and electronic properties. They are considered as promising candidates for practical applications in (opto)electronics and photovoltaics, for instance, in solar cells or

• on TiO2 [67]. For clarity, the simplified schematic drawings of the α and β phases and our models are shown in Figure 4. In order to acquire information on the electronic properties of the FePc molecules within the islands on the Ge(001):H we have performed STS measurements. Figure 5 shows a single

TiO_x/Pt₃Ti(111) surface-directed formation of electronically responsive supramolecular assemblies of tungsten oxide clusters

• Marco Moors,
• Yun An,
• Agnieszka Kuc and
• Kirill Yu. Monakhov

Beilstein J. Nanotechnol. 2021, 12, 203–212, doi:10.3762/bjnano.12.16

• exhibit unique electronic properties [21][23]. Thus, it is not surprising that the adsorption on such positions may result in extraordinary arrangements. As a consequence of this supramolecular assembly, the risen cluster in the center does not have a direct contact with the metallic substrate or with the

• phase strongly support this theory (see Figure 4). The calculated geometries of both clusters are D3h and Cs for W3O9 and W3O8, respectively. The bond length distribution strongly changes, especially close to WIV. This results in strongly changed electronic properties. Two different oxidation states are

• electronic properties were obtained by employing PBE exchange–correlation functional [32] with the D3(BJ) dispersion correction [33][34][35], the valence triple-zeta polarized (TZP) basis sets composed of Slater-type and numerical orbitals, and scalar zero-order regular approximation (ZORA) [36]. STM images

ZnO and MXenes as electrode materials for supercapacitor devices

• Ameen Uddin Ammar,
• Ipek Deniz Yildirim,
• Feray Bakan and
• Emre Erdem

Beilstein J. Nanotechnol. 2021, 12, 49–57, doi:10.3762/bjnano.12.4

• , recently developed metal oxides, specifically nanostructured ZnO, and MXenes with their defect structures, size effects, as well as optical and electronic properties have been presented as electrode material in supercapacitor devices. The discussion of MXenes along with ZnO, although different in chemistry

Free and partially encapsulated manganese ferrite nanoparticles in multiwall carbon nanotubes

• Saja Al-Khabouri,
• Salim Al-Harthi,
• Toru Maekawa,
• Mohamed E. Elzain,
• Ashraf Al-Hinai,
• Ahmed D. Al-Rawas,
• Abbsher M. Gismelseed,
• Ali A. Yousif and
• Myo Tay Zar Myint

Beilstein J. Nanotechnol. 2020, 11, 1891–1904, doi:10.3762/bjnano.11.170

• nanoparticles [15], as confirmed by the line profile shown in Figure 1d. In order to investigate the electronic properties of free MnFe2O4 nanoparticles, ultraviolet photoelectron spectroscopy was employed. Even though theoretical studies have been reported for MnFe2O4 [16], to the best of our knowledge, these

Detecting stable adsorbates of (1S)-camphor on Cu(111) with Bayesian optimization

• Jari Järvi,
• Patrick Rinke and
• Milica Todorović

Beilstein J. Nanotechnol. 2020, 11, 1577–1589, doi:10.3762/bjnano.11.140

• electronic properties of the material. Assemblies of organic molecules on surfaces have been studied experimentally, for example with X-ray diffraction [4][5], scanning tunneling microscopy [6][7][8] and atomic force microscopy (AFM) [9][10][11]. These methods have a considerable resolution in imaging planar

• and mobility via the energy barriers on the PES, and investigate their electronic properties with DFT. Bayesian Optimization Structure Search With the atomic structures and their corresponding energies, BOSS constructs a surrogate model of the PES. We define the atomic structures using chemical

• the molecule via oxygen (class Ox) and (b) physisorption via hydrogen (class Hy). (c) Adsorption site of camphor in the relaxed structures (center of the molecule) and the high-symmetry points of the Cu(111) surface. Electronic properties of different camphor adsorbates. (a) The sum of partial charges

Controlling the electronic and physical coupling on dielectric thin films

• Philipp Hurdax,
• Michael Hollerer,
• Larissa Egger,
• Georg Koller,
• Xiaosheng Yang,
• Anja Haags,
• Serguei Soubatch,
• Frank Stefan Tautz,
• Mathias Richter,
• Alexander Gottwald,
• Peter Puschnig,
• Martin Sterrer and
• Michael G. Ramsey

Beilstein J. Nanotechnol. 2020, 11, 1492–1503, doi:10.3762/bjnano.11.132

• ), 10587 Berlin, Germany 10.3762/bjnano.11.132 Abstract Ultrathin dielectric/insulating films on metals are often used as decoupling layers to allow for the study of the electronic properties of adsorbed molecules without electronic interference from the underlying metal substrate. However, the presence

Self-assembly and spectroscopic fingerprints of photoactive pyrenyl tectons on hBN/Cu(111)

• Domenik M. Zimmermann,
• Knud Seufert,
• Luka Ðorđević,
• Tobias Hoh,
• Sushobhan Joshi,
• Tomas Marangoni,
• Davide Bonifazi and
• Willi Auwärter

Beilstein J. Nanotechnol. 2020, 11, 1470–1483, doi:10.3762/bjnano.11.130

• allows the determination of the electronic properties of the pyrene adsorbates by STM and STS", and the comparison with the gaps estimated by theoretical simulations in vacuum and by UV-vis spectroscopies in solution. Remarkably, the electronic states of the pyrene adsorbates near the Fermi level, probed

• Structural and electronic properties in vacuum The pyrenyl derivatives studied in this work are shown in Figure 1a and have been prepared following previous synthetic protocols [48]. The highest molecular symmetry is given by the tetrasubstituted species 1, namely 1,3,6,8-tetrakis(pyridin-4-ylethynyl)pyrene

• effect of the substitution on the electronic properties of the pyrene core, DFT calculations were performed (B3LYP/6-31G** level of theory, in vacuum). The frontier Kohn-Sham orbitals of pyrene and the di- and tetrasubstituted (pyridin-4-ylethynyl)pyrenes 1, 2, and 3 are shown in Figure 1b (see also

Impact of fluorination on interface energetics and growth of pentacene on Ag(111)

• Qi Wang,
• Meng-Ting Chen,
• Antoni Franco-Cañellas,
• Bin Shen,
• Thomas Geiger,
• Holger F. Bettinger,
• Frank Schreiber,
• Ingo Salzmann,
• Alexander Gerlach and
• Steffen Duhm

Beilstein J. Nanotechnol. 2020, 11, 1361–1370, doi:10.3762/bjnano.11.120

• Morgenstelle 18, 72076 Tübingen, Germany Department of Physics, Department of Chemistry & Biochemistry, Concordia University, 7141 Sherbrooke St. West, Montreal, Quebec H4B 1R6, Canada 10.3762/bjnano.11.120 Abstract We studied the structural and electronic properties of 2,3,9,10-tetrafluoropentacene (F4PEN

Controlling the proximity effect in a Co/Nb multilayer: the properties of electronic transport

• Sergey Bakurskiy,
• Mikhail Kupriyanov,
• Nikolay V. Klenov,
• Igor Soloviev,
• Andrey Schegolev,
• Roman Morari,
• Yury Khaydukov and
• Anatoli S. Sidorenko

Beilstein J. Nanotechnol. 2020, 11, 1336–1345, doi:10.3762/bjnano.11.118

• parameter regions where the aforementioned switching between the P and AP orientations of the F1 and F2 layers is possible were found experimentally. In this work, we perform theoretical and experimental analyses of electronic properties of Nb/Co multilayers with different F1 and F2 thicknesses and several

Effect of localized helium ion irradiation on the performance of synthetic monolayer MoS₂ field-effect transistors

• Jakub Jadwiszczak,
• Pierce Maguire,
• Conor P. Cullen,
• Georg S. Duesberg and
• Hongzhou Zhang

Beilstein J. Nanotechnol. 2020, 11, 1329–1335, doi:10.3762/bjnano.11.117

• exploration of nanometer-scale structural modifications of TMD devices [6][7][8]. The localized formation of defects by focused ion beam irradiation has been shown to induce unusual electronic properties in monolayer TMDs, such as pseudo-metallic phase transitions in MoS2 and WSe2 [9][10], resistive switching

Structural and electronic properties of SnO₂ doped with non-metal elements

• Jianyuan Yu,
• Yingeng Wang,
• Yan Huang,
• Xiuwen Wang,
• Jing Guo,
• Jingkai Yang and
• Hongli Zhao

Beilstein J. Nanotechnol. 2020, 11, 1321–1328, doi:10.3762/bjnano.11.116

• Technology Tangshan Public Service Platform, Tangshan, Hebei 063000, China School of Civil Engineering, Tangshan University, Tangshan, Hebei 063000, China State Key Laboratory of Metastable Materials Science and Technology, China 10.3762/bjnano.11.116 Abstract Crystal structure and electronic properties of

Growth of a self-assembled monolayer decoupled from the substrate: nucleation on-command using buffer layers

• Robby Reynaerts,
• Kunal S. Mali and
• Steven De Feyter

Beilstein J. Nanotechnol. 2020, 11, 1291–1302, doi:10.3762/bjnano.11.113

• formation by acting as a physical barrier between the substrate and the assembling moiety, buffer layers are also widely used to study intrinsic electronic properties of functional organic systems such as organic semiconductors [32][33] and films of 1D/2D polymers [34][35][36][37] via electronic decoupling

• . Alkane buffer layers have been employed as efficient electronic decoupling platforms for studying the intrinsic electronic properties of graphene and fullerenes [38]. Apart from alkane derivatives, inorganic systems such as chemisorbed iodine layers [34][35][36][37], and ultrathin layers of KCl [39

Hybridization vs decoupling: influence of an h-BN interlayer on the physical properties of a lander-type molecule on Ni(111)

• Maximilian Schaal,
• Takumi Aihara,
• Marco Gruenewald,
• Felix Otto,
• Jari Domke,
• Roman Forker,
• Hiroyuki Yoshida and
• Torsten Fritz

Beilstein J. Nanotechnol. 2020, 11, 1168–1177, doi:10.3762/bjnano.11.101

• with the bands of the metal substrate, which results in changes of the intrinsic optical and electronic properties of the adsorbed molecule. This process is referred to as hybridization, which may be accompanied by the reduction of the HOMO–LUMO gap, the change of the energy-level alignment, and even

• , structural and electronic properties of DBP on Ni(111). By inserting the h-BN layer, we fabricated a buried interface, and a monomer-like behavior was observed by means of DRS instead of a strong hybridization, which occurs on the bare metal substrate. Therefore, we conclude that one h-BN layer is sufficient

• commercial software LEEDLab [50] for the quantitative LEED analysis. The LT-STM images were only modified by a mean plane subtraction. The electronic properties were investigated by PES with monochromatized Al Kα (SPECS Focus 500, Eexcitation = 1486.71 eV), monochromatized and p-polarized He Iα (SPECS UVLS

Monolayers of MoS₂ on Ag(111) as decoupling layers for organic molecules: resolution of electronic and vibronic states of TCNQ

• Asieh Yousofnejad,
• Gaël Reecht,
• Nils Krane,
• Christian Lotze and
• Katharina J. Franke

Beilstein J. Nanotechnol. 2020, 11, 1062–1071, doi:10.3762/bjnano.11.91

• on Au(111). Before discussing the differences between the layers on Au(111) and Ag(111), we investigate the effect of the different stacking at the interface on the electronic properties. The spectrum of a hollow site on Ag(111) shows a shift of the features at negative bias voltage by about approx

• moiré pattern. Hence, we suggest that this site is most strongly affected by screening effects, which may vary on the different substrates [46] and partially compensate for hybridization effects. Electronic properties of TCNQ molecules on MoS2 on Ag(111) Deposition of TCNQ molecules (structure shown in

• ascribed to a combination of its rather large thickness of three atomic layers, its electronic bandgap, and its non-ionic nature. Together, these properties prohibited fast electronic relaxations into the metal and coupling to phonons, which otherwise led to lifetime broadening [27][28]. The electronic

A new photodetector structure based on graphene nanomeshes: an ab initio study

• Babak Sakkaki,
• Hassan Rasooli Saghai,
• Ghafar Darvish and
• Mehdi Khatir

Beilstein J. Nanotechnol. 2020, 11, 1036–1044, doi:10.3762/bjnano.11.88

• structure of large systems, which cannot be obtained from conventional ab initio methods. Results and Discussion Electrical and optical properties We first calculate the electronic properties of the GNR and GNM structures using ab initio calculations and then obtain the absorption spectrum of these

• , preparing holes with the exact planned atomic structure is very challenging due to effect of atomic edge disorder within the holes. Nguyen et al. [31] showed that the edge disorder in GNMs could entirely alter the electronic properties. To model the disorder, they removed the carbon atoms in the edge of

• to bottom and obtained their FOMs, which were compared to those of also investigated GNR-based detectors. First, DFT calculations were used to obtain the electronic properties. Later, by using non-equilibrium Green’s functions within a DFTB model and first-order perturbation theory, we have

Measurement of electrostatic tip–sample interactions by time-domain Kelvin probe force microscopy

• Christian Ritz,
• Tino Wagner and
• Andreas Stemmer

Beilstein J. Nanotechnol. 2020, 11, 911–921, doi:10.3762/bjnano.11.76

• component at ωm by adjusting Udc. The surface potential is then found as Ulcpd = Udc. The response at the second harmonic contains additional information about the capacitance gradient C′′ = ∂2C/∂z2. This signal is interesting in itself as it contains information about both geometric and electronic

• properties of tip and sample, e.g., the dielectric properties of a sample or the quantum capacitance [14]. Furthermore, this signal can be used to adjust the sensitivity of the KFM feedback loop [15]. Open-loop KFM techniques exploit the relationship of the contributions at ωm and 2ωm. Namely, Ulcpd can be

Templating effect of single-layer graphene supported by an insulating substrate on the molecular orientation of lead phthalocyanine

• K. Priya Madhuri,
• Abhay A. Sagade,
• Pralay K. Santra and
• Neena S. John

Beilstein J. Nanotechnol. 2020, 11, 814–820, doi:10.3762/bjnano.11.66

• found to be 2.82 nm. Wang et al. carried out a similar study by depositing a 10 nm thin ZnPc film on a graphene/SiO2/Si substrate to study the effects of the molecular orientation on the interfacial electronic properties. The roughness of the film was reported to be 2.47 ± 0.28 nm [19]. The crystallite

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

• (LDA) computations suggests a lower indirect gap around 4 eV. Calculations with other methods suggest a higher value of about 5.95 eV [87]. In experiments, the variability of the properties is even larger. For example, stacking influences the electronic properties of h-BN [86]. The indirect bandgap is

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

• electronic devices have been realized by heterostructures based on vertical stacking or lateral stitching of 2D materials with different electronic properties [6]. Lateral graphene/hexagonal boron nitride (Gr/hBN) heterostructures, due to very low lattice mismatch between graphene and hBN, are most suitable

• 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