Unveiling the nature of atomic defects in graphene on a metal surface

• Karl Rothe,
• Nicolas Néel and
• Jörg Kröger

Beilstein J. Nanotechnol. 2024, 15, 416–425, doi:10.3762/bjnano.15.37

• on Pt(111) [14], and SiC() [16]. These resonances were interpreted as a collective excitation of the graphene π orbitals near the void [54], which depends on the coupling of the C atoms to the substrate surface. Therefore, the graphene–surface hybridization plays an important role in the occurrence

• of this resonance. Indeed, the resonance was not observed at all graphene defects on Pt(111). At some sites, it was quenched because of an increased interaction between the defect and the metal [55]. Therefore, the absence of a similar resonance in dI/dV spectra of graphene defects on Ir(111) may be

• due to an increased graphene–metal interaction compared with Pt(111), although both graphene–metal hybrid structures belong to the weak-hybridization regime [43]. Another rationale is the deviation of the observed defects 1 and 2 from a monatomic vacancy site, which will further be explored in the

Studies of probe tip materials by atomic force microscopy: a review

• Ke Xu and
• Yuzhe Liu

Beilstein J. Nanotechnol. 2022, 13, 1256–1267, doi:10.3762/bjnano.13.104

• curve is obtained with the same tip after exchanging the sample with a G/Pt(111) surface. Acquisition parameters: fo = 168274 Hz; k = 33.3 N/m; red curve: VCPD = −0.1 V; A = 13.5 nm. Blue curve: VCPD = −0.45 V; A = 16 nm. Black curve: VCPD = +0.2 V; A = 19.2 nm. (b) Atomically resolved NC-AFM image of

• the G/Pt(111) surface obtained with the cluster tip. Image size: 3.5 × 3.5 nm2. Imaging parameters: A =14.5 nm; VCPD = +0.18 V; Δf = −5.5 Hz. Figure 1 was reproduced from [25] (© 2021 M. D. Jiménez-Sánchez et al., published by Elsevier, distributed under the terms of the Creative Commons Attribution

Molecular assemblies on surfaces: towards physical and electronic decoupling of organic molecules

• Sabine Maier and
• Meike Stöhr

Beilstein J. Nanotechnol. 2021, 12, 950–956, doi:10.3762/bjnano.12.71

• , or metals [83]. Rothe et al. [84] demonstrated that semimetallic graphene is an appropriate buffer layer for the physical and chemical decoupling of rubrene from Pt(111). The strong molecule–surface interaction on Pt(111) is expressed by hit-and-stick adsorption due to a substantial diffusion barrier

• . In contrast, on graphene/Pt(111) the growth of molecular domains is facilitated. Electronically, the width of the highest occupied molecular orbital (HOMO) resonance is reduced by a factor of ten on graphene/Pt(111) compared to bare Pt(111) due to a reduction of the molecule–surface hybridization

• . The significantly reduced resonance width allowed for resolving vibronic states in both frontier orbitals on graphene/Pt(111) by STS. The semiconducting 2D material MoS2 may act as a decoupling layer for molecules from the underlying metal substrate if the molecular resonances lie within the MoS2

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

• surfaces by using high-resolution scanning tunneling microscopy (STM), in particular on TiO2(110) [15][16], CuO(110) [17], and Pt(111) [18]. Recently, the surface behavior of W3O9 was assessed on a complex CuWO3 phase grown on Cu(110). The CuWO3/Cu(110) substrate can be viewed as a two-dimensional (2D

• resolution as a triangular structure representing the unoccupied electronic states of the tungsten atoms. On pure oxide surfaces the clusters showed no substantial long-range order and they tended to form agglomerates at higher coverages [15][16][17]. In contrast to that, the W3O9 clusters on Pt(111) formed

• points, identical oxide phases by electron beam evaporation of Ti on Pt(111) at increased oxygen partial pressures. However, the direct oxidation of the Pt3Ti alloy surface has the advantage of an easier reproducibility and an increased long-range order of the individual oxide phases [22]. For this study

The influence of an interfacial hBN layer on the fluorescence of an organic molecule

• Christine Brülke,
• Oliver Bauer and
• Moritz M. Sokolowski

Beilstein J. Nanotechnol. 2020, 11, 1663–1684, doi:10.3762/bjnano.11.149

• al. [23] investigated the optical absorption properties of PTCDA on hBN/Rh(111) and hBN/Pt(111). Here, we report a direct comparison of FL spectra of PTCDA/hBN/Cu(111) and PTCDA/Cu(111), which allows for a relative determination of the efficiency of the hBN layer to decouple the excited states of

• values are given in Table 2. Note that only PTCDA/hBN/SiO2 was investigated by FL spectroscopy while for PTCDA/hBN/Pt(111) and PTCDA/hBN/Rh(111) absorption spectra were measured. We cannot explain the differences of the S0/S1 transition energies, yet. However, we observe a trend of higher transition

• energies from hBN/SiO2 to hBN/Cu(111) to hBN/Pt(111) to hBN/Rh(111). This is the direction of increasing interactions between the hBN layer and the supporting metal substrate, as indicated by the increasing amplitude of the buckling of the hBN layers [30][66]. We note that Forker et al. [23] could exclude

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

• coverages of PTCDA and MnPc on the strongly corrugated hBN/Rh(111) support [21][22][80], with computational modeling showing PTCDA rings positioned above the N sites of a hBN flake [14]. In contrast, no preferred orientations have been identified for a hydrocarbon lander molecule (i.e., DBP) on hBN/Pt(111

Scanning tunneling microscopy and spectroscopy of rubrene on clean and graphene-covered metal surfaces

• Karl Rothe,
• Alexander Mehler,
• Nicolas Néel and
• Jörg Kröger

Beilstein J. Nanotechnol. 2020, 11, 1157–1167, doi:10.3762/bjnano.11.100

• Karl Rothe Alexander Mehler Nicolas Neel Jorg Kroger Institut für Physik, Technische Universität Ilmenau, D-98693 Ilmenau, Germany 10.3762/bjnano.11.100 Abstract Rubrene (C42H28) was adsorbed with submonolayer coverage on Pt(111), Au(111), and graphene-covered Pt(111). Adsorption phases and

• vibronic properties of C42H28 consistently reflect the progressive reduction of the molecule–substrate hybridization. Separate C42H28 clusters are observed on Pt(111) as well as broad molecular resonances. On Au(111) and graphene-covered Pt(111) compact molecular islands with similar unit cells of the

• vibrations. In the work presented here, 5,6,11,12-tetraphenyltetracene (rubrene, C42H28, Figure 1) was adsorbed on different surfaces, namely Pt(111), Au(111), and graphene on Pt(111), in order to demonstrate a gradual reduction of the C42H28–surface hybridization. The choice of the molecule and substrate

Antimony deposition onto Au(111) and insertion of Mg

• Lingxing Zan,
• Da Xing,
• Abdelaziz Ali Abd-El-Latif and
• Helmut Baltruschat

Beilstein J. Nanotechnol. 2019, 10, 2541–2552, doi:10.3762/bjnano.10.245

• , which is about the same as in the first cycle and probably corresponds to same continuous incorporation of Sb into the surface to form the surface alloy. The behavior of Sb UPD on Au(111) is somewhat different from that on Pt(111) [26]. There, after the first deposition of Sb in peak C1 (occurring at

Coexistence of strongly buckled germanene phases on Al(111)

• Weimin Wang and
• Roger I. G. Uhrberg

Beilstein J. Nanotechnol. 2017, 8, 1946–1951, doi:10.3762/bjnano.8.195

• metallic substrates and band gap materials. Bampoulis et al. [7] proposed a germanene layer with very small buckling (0.2 Å) when they made Pt/Ge crystals by depositing and annealing of Pt on Ge(110). In an inverse case, Li et al. [8] chose Pt(111) as a substrate onto which Ge was evaporated at room

• temperature. This choice of substrate was motivated by a weaker interfacial interaction compared to other metals with adsorbed two-dimensional sheets such as graphene. They reported that Ge formed a (√19×√19) superstructure on the Pt(111) surface. A model based on a distorted, buckled, germanene sheet was

• “silicene” on Pt(111). Based on their theoretical calculation, they believed that a Si3Pt surface alloy was formed that resembles a twisted kagome lattice. By an extension of their interpretation, they suggested that the (√19×√19) superstructure of Ge on Pt(111) in [8] is also a surface alloy composed of

Nitrogen-doped twisted graphene grown on copper by atmospheric pressure CVD from a decane precursor

• Ivan V. Komissarov,
• Nikolai G. Kovalchuk,
• Vladimir A. Labunov,
• Ksenia V. Girel,
• Olga V. Korolik,
• Mikhail S. Tivanov,
• Algirdas Lazauskas,
• Mindaugas Andrulevičius,
• Tomas Tamulevičius,
• Viktoras Grigaliūnas,
• Šarunas Meškinis,
• Sigitas Tamulevičius and
• Serghej L. Prischepa

Beilstein J. Nanotechnol. 2017, 8, 145–158, doi:10.3762/bjnano.8.15

• fact that most of the carbon atoms are arranged into a honeycomb lattice. The sp2C peak of graphene could be observed at various values of energy depending on the material of the substrate on which graphene was deposited. The peak position varies from 283.97 eV for graphene on Pt(111) [32][33] to

Experimental and simulation-based investigation of He, Ne and Ar irradiation of polymers for ion microscopy

• Lukasz Rzeznik,
• Yves Fleming,
• Tom Wirtz and
• Patrick Philipp

Beilstein J. Nanotechnol. 2016, 7, 1113–1128, doi:10.3762/bjnano.7.104

• of the sample under ion bombardment is obtained. As an example, one may cite molecular dynamics (MD) simulations of Ar+ irradiation on a benzene overlayer on a Ni(001) surface [17] and on an ethylidyne (C2H3) overlayer on a Pt(111) substrate [18]. Ion bombardment on polymers was reported first for 1

Distribution of Pd clusters on ultrathin, epitaxial TiO_x films on Pt₃Ti(111)

• Christian Breinlich,
• Maria Buchholz,
• Marco Moors,
• Tobias Pertram,
• Conrad Becker and
• Klaus Wandelt

Beilstein J. Nanotechnol. 2015, 6, 2007–2014, doi:10.3762/bjnano.6.204

• described the detailed protocol on how to grow these TiOx films by direct oxidation of the Pt3Ti(111) surface at elevated temperatures [6]. Granozzi et al., who found very similar phases by “reactive evaporation” of titanium onto a Pt(111) surface in oxygen [7], introduced the notation z'-TiOx (zigzag-like

• ) for the rectangular and w'-TiOx (wagon-wheel-like) for the hexagonal oxide phase, according to their appearance in STM images. Due to the similarity of our films to those described for Pt(111), we decided to simply adopt the same nomenclature throughout this paper. The rectangular z'-TiOx phase

• the resulting films and their improved reproducibility compared to films grown by “reactive evaporation” [7]. Both the z'-TiOx phase on Pt(111) and the Moiré superstructure of the alumina film on Ni3Al(111) have already been proven to be excellent templates for the ordered growth of metal clusters

Lower nanometer-scale size limit for the deformation of a metallic glass by shear transformations revealed by quantitative AFM indentation

• Arnaud Caron and
• Roland Bennewitz

Beilstein J. Nanotechnol. 2015, 6, 1721–1732, doi:10.3762/bjnano.6.176

• Abstract We combine non-contact atomic force microscopy (AFM) imaging and AFM indentation in ultra-high vacuum to quantitatively and reproducibly determine the hardness and deformation mechanisms of Pt(111) and a Pt57.5Cu14.7Ni5.3P22.5 metallic glass with unprecedented spatial resolution. Our results on

• plastic deformation mechanisms of crystalline Pt(111) are consistent with the discrete mechanisms established for larger scales: Plasticity is mediated by dislocation gliding and no rate dependence is observed. For the metallic glass we have discovered that plastic deformation at the nanometer scale is

• nanometer-scale contacts between an AFM-tip and a Pt(111) single crystal on the one hand, and a Pt57.5Cu14.7Ni5.3P22.5 metallic glass on the other hand. In order to investigate plasticity mechanisms at the nanometer-scale, AFM indentation experiments were performed with varying maximal loads and varying

Enhanced fullerene–Au(111) coupling in (2√3 × 2√3)R30° superstructures with intermolecular interactions

• Michael Paßens,
• Rainer Waser and
• Silvia Karthäuser

Beilstein J. Nanotechnol. 2015, 6, 1421–1431, doi:10.3762/bjnano.6.147

• surfaces, such as Ag(111) [17][18], Cu(111) [19][20] and Pt(111) [21][22][23], and therefore seems to be the rule rather than the exception. Moreover, it could be shown by STM investigations that the self-assembly of C60 on Au(111) surfaces causes the partial or complete lifting of the herringbone

• suggestion is supported by the superstructures of dim C60 molecules observed on Pt(111) and Cu(111) surfaces after an annealing step at 1100 K [22] and 560 K [34], respectively. Moreover, a successive change from bright to dim C60-molecules on the Cu(111)-surface was monitored during annealing cycles and

• to the C60 marked with a blue circle in Figure 4d. This scenario is promoted by a first-principles study of C60 on a Pt(111) surface [40]. Here, it was concluded that Pt adatoms resulting from vacancy–adatom formation are located in the interstitial regions between the C60 molecules on the Pt(111

Tunable magnetism on the lateral mesoscale by post-processing of Co/Pt heterostructures

• Oleksandr V. Dobrovolskiy,
• Maksym Kompaniiets,
• Roland Sachser,
• Fabrizio Porrati,
• Christian Gspan,
• Harald Plank and
• Michael Huth

Beilstein J. Nanotechnol. 2015, 6, 1082–1090, doi:10.3762/bjnano.6.109

• , the bright rings (111), (200), (220) and (311) are expected for both lattices while the main reflections are dominated by Pt. At the same time, a weak additional diffraction intensity within the innermost Pt (111) ring suggests the presence of some smaller contribution from a CoPt fct phase, thereby

Stick–slip behaviour on Au(111) with adsorption of copper and sulfate

• Nikolay Podgaynyy,
• Sabine Wezisla,
• Christoph Molls,
• Shahid Iqbal and
• Helmut Baltruschat

Beilstein J. Nanotechnol. 2015, 6, 820–830, doi:10.3762/bjnano.6.85

• friction forces on single crystal electrodes under electrochemical conditions. In [10][11] we investigated the effect of copper under potential deposition (UPD) on Au(111) and Pt(111) on friction and found an increase in friction force after adsorption of a sub- or monolayer of copper. A particularly high

• zero Cu coverage into the copper 2/3 adlayer region [10]. A similar effect was observed previously on Pt(111) during the formation of a copper monolayer [11]. Bennewitz et al. observed such an increase on Au(111) upon Cu adsorption during potential cycling [12]. Obviously, this increase in friction is

Magnetic properties of self-organized Co dimer nanolines on Si/Ag(110)

• Lisa Michez,
• Kai Chen,
• Fabien Cheynis,
• Frédéric Leroy,
• Alain Ranguis,
• Haik Jamgotchian,
• Margrit Hanbücken and
• Laurence Masson

Beilstein J. Nanotechnol. 2015, 6, 777–784, doi:10.3762/bjnano.6.80

• evaluate the spin and orbital contributions to the magnetization of the Co nanolines. The number of holes in the Co 3d band is estimated to be 2.5, which corresponds to the average theoretical value for bulk Co [40][41]. Note that a similar value of 2.4 has been found for the case of Co adatoms on Pt(111

X-ray photoelectron spectroscopy of graphitic carbon nanomaterials doped with heteroatoms

• Toma Susi,
• Thomas Pichler and
• Paola Ayala

Beilstein J. Nanotechnol. 2015, 6, 177–192, doi:10.3762/bjnano.6.17

• around 284.6 eV. However, even if this were the case, the influence of the second layer might still have an effect. As we discuss below, in the available measurements on monolayer graphene, it is clear that the role of the surface cannot be discounted. A recent measurement of graphene on Pt(111) by

• . Values of 284.15 [76][78] and 284.2 eV [69][70] have been measured on Ir(111) and Au-intercalated Ni(111) surfaces, respectively. C 1s values for graphene on other metal surfaces range from as low as 283.97 eV on Pt(111) [76][77], to 284.5 eV on Cu(111) [72], and 284.7 eV on Ni(111) [68]. The range of

Morphology, structural properties and reducibility of size-selected CeO_2−x nanoparticle films

• Maria Chiara Spadaro,
• Sergio D’Addato,
• Gabriele Gasperi,
• Francesco Benedetti,
• Paola Luches,
• Vincenzo Grillo,
• Giovanni Bertoni and
• Sergio Valeri

Beilstein J. Nanotechnol. 2015, 6, 60–67, doi:10.3762/bjnano.6.7

• UHV apparatus was used to grow both epitaxial and non-epitaxial cerium oxide ultrathin films for comparison. The system is equipped with facilities for substrate preparation, film growth, in situ XPS, and scanning tunnelling microscopy (STM) analysis. The substrate used for film growth was a Pt(111

• deposition in pO2 = 1·10−7 mbar at room temperature and post-growth annealing at T = 1040 K under the same O2 partial pressure. A non-epitaxial cerium oxide film grown on Pt(111) with nominal thickness t = 2 ML, was obtained with the same procedures as the epitaxial film, without the post-growth annealing in

• size and a few angstroms in average height. After annealing the film up to T = 1040 K in O2 we obtained an epitaxial ceria thin film as shown in Figure 2e, in which the islands have atomically flat surfaces. In this case 45% of the Pt(111) substrate is covered and the islands have a mean height of 0.6

Cathode lens spectromicroscopy: methodology and applications

• T. O. Menteş,
• G. Zamborlini,
• A. Sala and
• A. Locatelli

Beilstein J. Nanotechnol. 2014, 5, 1873–1886, doi:10.3762/bjnano.5.198

• for graphene on Pt(111) and Ir(111) surfaces [61][62]. Importantly, no coincidence structures are observed in the LEED pattern, which exhibits only the first order graphene spots plus an extremely week moiré structure, identical to that observed on the flat phase of graphene on Ir(100). This finding

• thermal reduction with LEEM and LEED was crucial in understanding the reversible changes in thin magnetite and hematite films grown on several substrates [75]. In particular, annealing in UHV led to substrate-dependent transformations of the iron oxide thin film: from hematite to magnetite on a Pt(111

• ). This observation corresponds to the thinnest magnetite crystal that shows magnetism. Beyond the self-organized crystal shapes at the micrometer scale, epitaxial iron-oxide films provide a variety of complex surface reconstructions at the atomic scale as usual for oxide surfaces [74]. Fe3O4 films on Pt

Restructuring of an Ir(210) electrode surface by potential cycling

• Khaled A. Soliman,
• Dieter M. Kolb,
• Ludwig A. Kibler and
• Timo Jacob

Beilstein J. Nanotechnol. 2014, 5, 1349–1356, doi:10.3762/bjnano.5.148

• after annealing of noble metal single crystal electrodes has been investigated earlier for Pt(111) [24], Pt(100) and Pt(110) surfaces [6]. It was reported that the use of CO as a cooling gas for Pt(110) leads to the formation of an unreconstructed (1×1) surface [6][25], while cooling in N2 preserves the

Sublattice asymmetry of impurity doping in graphene: A review

• James A. Lawlor and
• Mauro S. Ferreira

Beilstein J. Nanotechnol. 2014, 5, 1210–1217, doi:10.3762/bjnano.5.133

• interactions between graphene and Al, Ag, Au, Pt(111) substrates, all of which leave the electronic structure intact [61], whilst substrates such as Ni have considerably stronger interactions [62]. Another way to investigate the presence of sublattice asymmetry with dopants other than nitrogen is via ion

Double layer effects in a model of proton discharge on charged electrodes

• Johannes Wiebe and
• Eckhard Spohr

Beilstein J. Nanotechnol. 2014, 5, 973–982, doi:10.3762/bjnano.5.111

• reactive force field procedure to statistically study the large number of proton transfer pathways by developing empirical valence bond (EVB) force fields for Grotthuss style proton migration and proton discharge at the water/Pt(111) [16][17] and the water/Ag(111) interface [18]. The first EVB models were

• qualitative representation of the proton transfer to the surface and the motion of the (discharged) hydrogen atom on the Pt(111) surface. The final MD model can be practically applied in MD simulations of the electrochemical interface. Among other things, it is Hamiltonian in nature and conserves total energy

Volcano plots in hydrogen electrocatalysis – uses and abuses

• Paola Quaino,
• Fernanda Juarez,
• Elizabeth Santos and
• Wolfgang Schmickler

Beilstein J. Nanotechnol. 2014, 5, 846–854, doi:10.3762/bjnano.5.96

• principle. At polycrystalline metals there are even more sites and therefore more options. The relation between the two species is not simple, since the energy of the weakly adsorbed hydrogen depends on the coverage with the upd species. The best investigated case is Pt(111) in acid solutions, where the

• in detail in a a recent communication [25], where we have also calculated the isotherms for both species of adsorbed hydrogen on Pt(111). In any case, the interaction between the two species makes it quite difficult to calculate the adsorption free energy of the true intermediate state by DFT. In the

• above, only Pt(111) and rhenium in acid solutions actually follow this path. Sheng et al. [34] have proposed a volcano plot for alkaline solutions. All of these plots lose their volcano shapes, once the oxide-covered metals are deleted. Besides hydrogen adsorption energies, correlations have been

Adsorption and oxidation of formaldehyde on a polycrystalline Pt film electrode: An in situ IR spectroscopy search for adsorbed reaction intermediates

• Zenonas Jusys and
• R. Jürgen Behm

Beilstein J. Nanotechnol. 2014, 5, 747–759, doi:10.3762/bjnano.5.87

• /negative band) were reported previously for formaldehyde oxidation over a Pt(111) electrode [6]. Those authors tentatively assigned them to the symmetric deformation (scissoring) mode of a –CH2– (or –O–CH2) group for the former and to the C–O stretching mode of a –COH group for the latter band in a

• intermediates in density functional theory based studies of the interaction of methanol with a Pt(111) surface [50]. The importance of water in the initial steps of dehydrogenation of methanol over Pt(111) via polarization of the hydroxyl due to hydrogen bond formation with a neighboring water molecule was

• surfaces were used to approximate the potential-dependent methanol dehydrogenation pathways over different low index Pt electrode surfaces [49]. These calculations revealed pronounced structural effects, in agreement with experimental findings. For Pt(111), they suggested the coexistence of two pathways