Thermal stability and reduction of iron oxide nanowires at moderate temperatures

• Annalisa Paolone,
• Marco Angelucci,
• Stefania Panero,
• Maria Grazia Betti and
• Carlo Mariani

Beilstein J. Nanotechnol. 2014, 5, 323–328, doi:10.3762/bjnano.5.36

• . Thermogravimetry measurements distinctly show the mass reduction due to oxygen loss, and infrared transmittance and core-level photoemission measurements allow to follow the reduction process of the iron ions at different temperatures, showing the chemical reduction to Fe3O4 starting at moderate temperatures

• (hν = 1486.7 eV), hemispherical electron analyzer with a pass energy of 100 eV. The binding energy (BE) with respect to the Fermi level has been calibrated at the Au-4f7/2 core level (84.0 eV BE). The iron oxide nanowires have been obtained by means of a hard template method. The hard template is

• of the Fe 3p core level. The XPS Fe 3p core-level data of the Fe2O3 NWs, taken at rt and after subsequent steps of thermal annealing, are shown in Figure 4. The Fe 3p signal of the clean Fe2O3 system at rt, which is roughly centered at 56 eV BE, presents the characteristic structure that is

Extracellular biosynthesis of gadolinium oxide (Gd₂O₃) nanoparticles, their biodistribution and bioconjugation with the chemically modified anticancer drug taxol

• Shadab Ali Khan,
• Sanjay Gambhir and
• Absar Ahmad

Beilstein J. Nanotechnol. 2014, 5, 249–257, doi:10.3762/bjnano.5.27

• eV) at a power of 200 watts was used. The binding energy of Au (4f7/2) at 84.0 ± 0.1 eV was used to calibrate the binding energy scale of the spectrometer. Any charging shift produced in the spectrum was corrected by referencing to the C (1s) position (284.6 eV) Background correction of core level

•  4D shows the N(1s) core level spectra that could be decomposed into two chemically distinct components centered at 399.6 and 402.5 eV and can be attributed to the neutral amino group NH2 and N atoms present in amide bonds of protein capping Gd2O3 nanoparticles [26]. These signatures of carbon and

• electron diffraction (SAED) pattern recorded from the Gd2O3 nanoparticles. XRD measurements of biosynthesized Gd2O3 nanoparticles. XPS data showing the (A) Gd(3d), (B) C(1s), (C) O(1s) and (D) N(1s) core level spectra recorded from biosynthesized Gd2O3 nanoparticles film cast onto a Si substrate. The raw

Core level binding energies of functionalized and defective graphene

• Toma Susi,
• Markus Kaukonen,
• Paula Havu,
• Mathias P. Ljungberg,
• Paola Ayala and
• Esko I. Kauppinen

Beilstein J. Nanotechnol. 2014, 5, 121–132, doi:10.3762/bjnano.5.12

• energies to specific bonding environments, reference energy values need to be known. Experimental measurements of the core level signals of the elements present in novel materials such as graphene have often been compared to values measured for molecules, or calculated for finite clusters. Here we have

• calculated core level binding energies for variously functionalized or defected graphene by delta Kohn–Sham total energy differences in the real-space grid-based projector-augmented wave density functional theory code (GPAW). To accurately model extended systems, we applied periodic boundary conditions in

• large unit cells to avoid computational artifacts. In select cases, we compared the results to all-electron calculations using an ab initio molecular simulations (FHI-aims) code. We calculated the carbon and oxygen 1s core level binding energies for oxygen and hydrogen functionalities such as graphane

Quantum size effects in TiO₂ thin films grown by atomic layer deposition

• Massimo Tallarida,
• Chittaranjan Das and
• Dieter Schmeisser

Beilstein J. Nanotechnol. 2014, 5, 77–82, doi:10.3762/bjnano.5.7

• spectroscopy (XAS). Synchrotron radiation (SR) based photoemission spectroscopy (PES) was also used to measure Ti 2p, O 1s and Si 2p core level spectra to determine the films thickness. Further, in order to study the TiO2 thin films in the sub-nanometer range, it was decisive to perform the spectroscopic

Ellipsometry and XPS comparative studies of thermal and plasma enhanced atomic layer deposited Al₂O₃-films

• Jörg Haeberle,
• Karsten Henkel,
• Hassan Gargouri,
• Franziska Naumann,
• Bernd Gruska,
• Michael Arens,
• Massimo Tallarida and
• Dieter Schmeißer

Beilstein J. Nanotechnol. 2013, 4, 732–742, doi:10.3762/bjnano.4.83

• with adsorbed methyl groups (284.5 eV) or adsorbed hydro-carbons (285 eV) but are inserted in an oxidic matrix. The formation of C–O bonds results in core level energies at around 286 eV (Figure 5). Second, the peak position of the C1s (Figure 5) varies in the same way as that of the Al2p and the O1s

• combination of these data with the C1s core level data (Figure 5) it becomes evident that the rt PE-ALD sample has the highest carbonate content leading to distinct contribution at higher IS energy within the O1s core level data. They compete with the above mentioned and below discussed peak shifting to lower

• IS energy. Therefore the O1s peak maximum of the rt PE-ALD sample is shifted to higher IS energy with respect to the T-ALD 200 °C sample whereas the peak maximum is moved to lower IS energy in the Al2p core level, where the carbonate has no influence. The same fact is due for the 80 °C PE-ALD sample

Pure hydrogen low-temperature plasma exposure of HOPG and graphene: Graphane formation?

• Baran Eren,
• Dorothée Hug,
• Laurent Marot,
• Rémy Pawlak,
• Marcin Kisiel,
• Roland Steiner,
• Dominik M. Zumbühl and
• Ernst Meyer

Beilstein J. Nanotechnol. 2012, 3, 852–859, doi:10.3762/bjnano.3.96

• (XPS and UPS) were used to monitor the changes in the core level and valence band structures of the HOPG after plasma exposure and subsequently after soft annealing. After exposure to hydrogen plasma, the core level C 1s spectrum gets broadened due to roughening, whereas it recovers its initial width

Towards atomic resolution in sodium titanate nanotubes using near-edge X-ray-absorption fine-structure spectromicroscopy combined with multichannel multiple-scattering calculations

• Carla Bittencourt,
• Peter Krüger,
• Maureen J. Lagos,
• Xiaoxing Ke,
• Gustaaf Van Tendeloo,
• Chris Ewels,
• Polona Umek and
• Peter Guttmann

Beilstein J. Nanotechnol. 2012, 3, 789–797, doi:10.3762/bjnano.3.88

• , Figure S1). The absence of extra peaks or broadening of the Ti 2p photoemission lines suggest that the chemical environment of the Ti ions does not change during the hydrothermal treatment of TiO2. The Ti L-edge shows two groups of peaks arising from the spin-orbit splitting of the Ti 2p core level into

X-ray absorption spectroscopy by full-field X-ray microscopy of a thin graphite flake: Imaging and electronic structure via the carbon K-edge

• Carla Bittencourt,
• Adam P. Hitchock,
• Xiaoxing Ke,
• Gustaaf Van Tendeloo,
• Chris P. Ewels and
• Peter Guttmann

Beilstein J. Nanotechnol. 2012, 3, 345–350, doi:10.3762/bjnano.3.39

• ]. Photoabsorption of X-rays creates core-level excited states in which a 1s electron is promoted into the unoccupied π* or σ* bands. In a planar system, such as graphene, there is a strong selection rule for this process with (1s−1, π*) final states being selectively excited when the E-vector lies perpendicular to

Investigation on structural, thermal, optical and sensing properties of meta-stable hexagonal MoO₃ nanocrystals of one dimensional structure

• Angamuthuraj Chithambararaj and
• Arumugam Chandra Bose

Beilstein J. Nanotechnol. 2011, 2, 585–592, doi:10.3762/bjnano.2.62

• an individual hexagonal rod. It shows two distinct edges at 532 eV (oxygen K edge) and 382 eV (molybdenum M edge), confirming the presence of only O and Mo with a covalent interaction [20]. The observed O-K edge peak reflects the electronic transitions from the oxygen 1 s core level to the unoccupied

• final state of O 2p hybridized with the Mo 4d state [21], and the Mo-M2,3 peak is due to excitation from 3p1/2 and 3p3/2 core level electrons to unoccupied states (4d and 5s) of molybdenum [22]. Growth mechanism and formation of 1D h-MoO3 On the basis of experimental results, the possible mechanism for

Extended X-ray absorption fine structure of bimetallic nanoparticles

• Carolin Antoniak

Beilstein J. Nanotechnol. 2011, 2, 237–251, doi:10.3762/bjnano.2.28

• on state-of-the-art X-ray absorption spectroscopy (XAS) on 3rd generation synchrotron sources such as the ESRF and BESSY II. In general, XAS deals with the excitation of core-level electrons, with their element-specific binding energies, by incident X-rays. After absorption of an X-ray photon, a core

Preparation and characterization of supported magnetic nanoparticles prepared by reverse micelles

• Ulf Wiedwald,
• Luyang Han,
• Johannes Biskupek,
• Ute Kaiser and
• Paul Ziemann

Beilstein J. Nanotechnol. 2010, 1, 24–47, doi:10.3762/bjnano.1.5

• results. Figure 6 shows Pt-4f and Fe-2p XP spectra of (9.8 ± 0.6) nm FePt NPs in the metallic state and after 24 h exposure to air. Oxidation in ambient air becomes obvious by a clear energy shift of the Fe 2p3/2 core level to about 711 eV with a shoulder at the metal position still present. By comparison