A sonochemical approach to the direct surface functionalization of superparamagnetic iron oxide nanoparticles with (3-aminopropyl)triethoxysilane

• Bashiru Kayode Sodipo and
• Azlan Abdul Aziz

Beilstein J. Nanotechnol. 2014, 5, 1472–1476, doi:10.3762/bjnano.5.160

• the band of Fe 2p3/2 and Fe 2p1/2 (Supporting Information File 1, Figure S5) that appears at 725.25 eV and 711.85 eV, respectively. The difference in their energy is 13.4 eV, which corresponds to 13.6 eV of Fe2O3 or Fe3O4. However, the XPS result alone cannot be used to determine the oxidation state

• of Fe in Fe2O3 or Fe3O4. This is due to similarity in the oxidation state of both iron oxide compounds. The chemical shifts observed in all the bands can be ascribed to the binding of the APTES on the SPION. The XRD pattern of the silanized SPION is shown in Figure 3. It corresponds to the JCPDS

Growth and characterization of CNT–TiO₂ heterostructures

• Yucheng Zhang,
• Ivo Utke,
• Johann Michler,
• Gabriele Ilari,
• Marta D. Rossell and
• Rolf Erni

Beilstein J. Nanotechnol. 2014, 5, 946–955, doi:10.3762/bjnano.5.108

• electrons and the resulting change of the oxidation state [61]. The damage mechanism can however depend on the specific chemical environment in the sample. To avoid the damage, optimized experimental conditions are required, such as a lower acceleration voltage or a lower probe current density. This should

Carbon dioxide hydrogenation to aromatic hydrocarbons by using an iron/iron oxide nanocatalyst

• Hongwang Wang,
• Jim Hodgson,
• Tej B. Shrestha,
• Prem S. Thapa,
• David Moore,
• Xiaorong Wu,
• Myles Ikenberry,
• Deryl L. Troyer,
• Donghai Wang,
• Keith L. Hohn and
• Stefan H. Bossmann

Beilstein J. Nanotechnol. 2014, 5, 760–769, doi:10.3762/bjnano.5.88

• by hydrogen, as the hydrogenation after run 6 indicates. The Fe 2p region (Figure 6) yields information about the oxidation state of iron in the particles. The small peak around 706.5 eV, which indicates Fe(0) is present in the fresh catalyst, but is absent after the catalyst has undergone 5 runs. It

Towards precise defect control in layered oxide structures by using oxide molecular beam epitaxy

• Federico Baiutti,
• Georg Christiani and
• Gennady Logvenov

Beilstein J. Nanotechnol. 2014, 5, 596–602, doi:10.3762/bjnano.5.70

• oxidation state of the transition metals in the ozone-assisted MBE strongly depends on the ozone concentration in the growth chamber, that is, the efficiency of the ozone delivery, as the ozone molecules lifetime is in the range of some seconds. To our knowledge, one of the most demanding tests to check if

Artificial sunlight and ultraviolet light induced photo-epoxidation of propylene over V-Ti/MCM-41 photocatalyst

• Van-Huy Nguyen,
• Shawn D. Lin,
• Jeffrey Chi-Sheng Wu and
• Hsunling Bai

Beilstein J. Nanotechnol. 2014, 5, 566–576, doi:10.3762/bjnano.5.67

• distinctive feature of MCM-41. The pore diameters of catalyst estimated from TEM was approximately 3 nm. We previously proposed that the titanium in V-Ti/MCM-41 should be Ti4+ with a tetrahedral coordination [17]. The K-edge XANES of vanadium (Figure 4) suggests its oxidation state to be V5+. A possible local

Mesoporous cerium oxide nanospheres for the visible-light driven photocatalytic degradation of dyes

• Subas K. Muduli,
• Songling Wang,
• Shi Chen,
• Chin Fan Ng,
• Cheng Hon Alfred Huan,
• Tze Chien Sum and
• Han Sen Soo

Beilstein J. Nanotechnol. 2014, 5, 517–523, doi:10.3762/bjnano.5.60

• radiation (hν = 1486.7 eV) were conducted. Unlike CeO2, in which the Ce atoms are all in the oxidation state 4+, the Ce atoms in Ce7O12 consist of both Ce3+ and Ce4+ valence states. The wide-scan survey spectrum in Figure 1b only shows Ce 3d, O 1s, and C 1s signals, and no other signals. The presence of the

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

• in Figure 3. The NWs assemble in bundles that are a few hundreds of nanometers thick and several micrometers long. The individual NWs are visible within the bundles, as long parallel nanometer-thick rods. After the thermal treatment that changes the oxidation state of Fe in the NW, they do not change

• higher temperature than what is to be expected in any device. The oxidation state of the Fe atoms can be determined by an analysis of the Fe core levels [28][29]. We confirm the thermally induced reduction at moderate temperatures of the Fe ions in the NWs by the X-ray photoemission spectroscopy analysis

• associated with multiple oxidation states [30][31][32]. We fit the experimental data with three Voigt (Lorentzian–Gaussian) functions with all peaks having the same Gaussian width (GW = 1.8 eV) and Lorentzian width (LW = 1.0 eV). The lineshape and BE of the Fe 3p core level confirm the Fe3+ oxidation state

Confinement dependence of electro-catalysts for hydrogen evolution from water splitting

• Mikaela Lindgren and
• Itai Panas

Beilstein J. Nanotechnol. 2014, 5, 195–201, doi:10.3762/bjnano.5.21

• according to This can be subdivided into an anode process where the [ZrIV–O–ZrIV] oxide grain boundary is recovered, and a cathode process is employed to decide the oxidation state X. The subsequent chemical drive for H2 release into the confining grain boundary determines M and recovers the [ZrIV–O–MX

• hydride-proton recombination reactions to demonstrate how it decides which oxidation state X of metal ion M minimizes the overpotential for the HER, as quantified by the reaction Equation 6 (cf. Figure 1d,e). Second, it is shown how the emerging understanding is naturally extended to include electro

• et al. [2]. Interestingly, +2 is not considered a relevant oxidation state in case of Pt under ambient conditions for the electro-catalytic reaction path involving the hydride-proton recombination reaction (see Figure 2). This result is due to the strong binding of +2 to the oxy-hydroxide ligands

Study of mesoporous CdS-quantum-dot-sensitized TiO₂ films by using X-ray photoelectron spectroscopy and AFM

• Mohamed N. Ghazzal,
• Robert Wojcieszak,
• Gijo Raj and
• Eric M. Gaigneaux

Beilstein J. Nanotechnol. 2014, 5, 68–76, doi:10.3762/bjnano.5.6

• 3d5/2 and Cd 3d3/2 is 6.7 eV, which corresponds to the presence of the oxidation state +2 of Cd 3d at the surface [20]. The S 2p3/3 peak (Figure 5) was found at 161.8 eV and is attributable to S2− in CdS [21]. The presence of other oxidation states is shown by the peak observed at 167.5 eV, which is

In situ growth optimization in focused electron-beam induced deposition

• Paul M. Weirich,
• Marcel Winhold,
• Christian H. Schwalb and
• Michael Huth

Beilstein J. Nanotechnol. 2013, 4, 919–926, doi:10.3762/bjnano.4.103

• structures, no reliable prediction can be made concerning its value for different deposition parameters and conditions. This is due to the fact that the metal content alone is not a sufficient indicator since in most instances transport is of the hopping type, so that the matrix composition and the oxidation

• state of the metal are also important but a-priori unknown quantities [4][8]. From this, one can conclude that the optimization of any FEBID process towards the largest possible conductivity should ideally monitor the conductance as the growth proceeds [10] and use this information in adaptively

Ferromagnetic behaviour of Fe-doped ZnO nanograined films

• Boris B. Straumal,
• Svetlana G. Protasova,
• Andrei A. Mazilkin,
• Thomas Tietze,
• Eberhard Goering,
• Gisela Schütz,
• Petr B. Straumal and
• Brigitte Baretzky

Beilstein J. Nanotechnol. 2013, 4, 361–369, doi:10.3762/bjnano.4.42

• cobalt demonstrates only one oxidation state Co3+ whereas manganese can possess several oxidation states, namely +2, +3 and +4 [17][18]. Together with cobalt and manganese, iron is one of the most important dopants in ZnO. Similar to manganese, iron has different oxidation states (Fe2+ and Fe3+). This

Catalytic activity of nanostructured Au: Scale effects versus bimetallic/bifunctional effects in low-temperature CO oxidation on nanoporous Au

• Lu-Cun Wang,
• Yi Zhong,
• Haijun Jin,
• Daniel Widmann,
• Jörg Weissmüller and
• R. Jürgen Behm

Beilstein J. Nanotechnol. 2013, 4, 111–128, doi:10.3762/bjnano.4.13

• of an intermediate oxidation state of gold, e.g., Au2O or AuO [74]. In combination with the rather low content of residual Cu in the NPG(Cu) sample, the peak observed in our TPD measurement (at 275 °C) should be assigned to desorption of atomic oxygen species chemisorbed on Au sites or decomposition

Structural and electronic properties of oligo- and polythiophenes modified by substituents

• Simon P. Rittmeyer and
• Axel Groß

Beilstein J. Nanotechnol. 2012, 3, 909–919, doi:10.3762/bjnano.3.101

• cannot address polarons, which are supposed to extend over five thiophene rings [18]. Still, our results may be helpful to understand trends in the band gap engineering. Furthermore, we note that it has been shown that changing the oxidation state through electrochemical potential control can have a

A facile approach to nanoarchitectured three-dimensional graphene-based Li–Mn–O composite as high-power cathodes for Li-ion batteries

• Wenyu Zhang,
• Yi Zeng,
• Chen Xu,
• Ni Xiao,
• Yiben Gao,
• Lain-Jong Li,
• Xiaodong Chen,
• Huey Hoon Hng and
• Qingyu Yan

Beilstein J. Nanotechnol. 2012, 3, 513–523, doi:10.3762/bjnano.3.59

• : chemical doping and microstructure modification. The chemical doping method involves elevating the average manganese ion oxidation state so as to decrease the amount of Mn3+ in LMO, e.g., by replacing manganese with monovalent [6] or multivalent cations [7][8][9]. However, doping into LMO tends to reduce

The morphology of silver nanoparticles prepared by enzyme-induced reduction

• Henrik Schneidewind,
• Thomas Schüler,
• Katharina K. Strelau,
• Karina Weber,
• Dana Cialla,
• Marco Diegel,
• Roland Mattheis,
• Andreas Berger,
• Robert Möller and
• Jürgen Popp

Beilstein J. Nanotechnol. 2012, 3, 404–414, doi:10.3762/bjnano.3.47

• silver deposition is activated by an enzymatic reaction leading to the growth of silver particles at the enzyme (c). In the enzymatic process an oxygen atom is split off from the hydrogen peroxide. This oxygen is bound to the heme group of HRP, thus changing the oxidation state of the iron atom inside

Nanostructured, mesoporous Au/TiO₂ model catalysts – structure, stability and catalytic properties

• Matthias Roos,
• Dominique Böcking,
• Kwabena Offeh Gyimah,
• Gabriela Kucerova,
• Joachim Bansmann,
• Johannes Biskupek,
• Ute Kaiser,
• Nicola Hüsing and
• R. Jürgen Behm

Beilstein J. Nanotechnol. 2011, 2, 593–606, doi:10.3762/bjnano.2.63

• limit of XPS (~0.01 ML), Cl could have measurable effects. XPS results The composition of the Au/TiO2 catalyst layer surface, in particular the oxidation state of the Au NPs and the amount of Au present in the film, was characterized by XPS, both before and after the oxidative pretreatment. Survey

Defects in oxide surfaces studied by atomic force and scanning tunneling microscopy

• Thomas König,
• Georg H. Simon,
• Lars Heinke,
• Leonid Lichtenstein and
• Markus Heyde

Beilstein J. Nanotechnol. 2011, 2, 1–14, doi:10.3762/bjnano.2.1

• probability density above the surface due to Coulomb repulsion. The charges are as for type II symmetrically distributed and located in the center of the defect, see Figure 8c. Therefore, the charge does not belong to any Mg2+ site surrounding the defect. Thus, the oxidation state of the surrounding lattice

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

• with literature data the main peak can be assigned to the Fe3+ oxidation state [69]. Interestingly, Pt-4f levels reveal no significant indication of oxide formation, proving the chemical state of the Pt atoms remains practically unchanged during oxidation of the FePt particles. This finding is