Evaluation of gas-sensing properties of ZnO nanostructures electrochemically doped with Au nanophases

• Elena Dilonardo,
• Michele Penza,
• Marco Alvisi,
• Cinzia Di Franco,
• Francesco Palmisano,
• Luisa Torsi and
• Nicola Cioffi

Beilstein J. Nanotechnol. 2016, 7, 22–31, doi:10.3762/bjnano.7.3

• electron microscopy (TEM, SEM), as well as X-ray photon electron spectroscopy (XPS), revealing the successful decoration of ZnO spherical and rod-like nanostructures, obtained at 300 and 550 °C, respectively, with nano-phase gold at the elemental oxidation state. The main focus of this study is to

Green and energy-efficient methods for the production of metallic nanoparticles

• Mitra Naghdi,
• Mehrdad Taheran,
• Satinder K. Brar,
• M. Verma,
• R. Y. Surampalli and
• J. R. Valero

Beilstein J. Nanotechnol. 2015, 6, 2354–2376, doi:10.3762/bjnano.6.243

• and prism-like NPs [22]. Polyoxometalates Polyoxometalates (POMs) are anionic structures with transition metal atoms in their highest oxidation state. These materials can exhibit tremendous structural variety and interesting properties such as reversible electron exchange behavior that make them ideal

The role of low-energy electrons in focused electron beam induced deposition: four case studies of representative precursors

• Rachel M. Thorman,
• Ragesh Kumar T. P.,
• D. Howard Fairbrother and
• Oddur Ingólfsson

Beilstein J. Nanotechnol. 2015, 6, 1904–1926, doi:10.3762/bjnano.6.194

• was monitored by XPS and RAIRS. The XPS spectra showed that the fractional Pt coverage stayed constant, but a partial reduction of Pt(IV) to a lower oxidation state took place. The C/Pt ratio decreased from the initial 9:1 of the precursor molecule to about 8:1 upon electron irradiation, as is shown

Thermal treatment of magnetite nanoparticles

• Beata Kalska-Szostko,
• Urszula Wykowska,
• Dariusz Satula and
• Per Nordblad

Beilstein J. Nanotechnol. 2015, 6, 1385–1396, doi:10.3762/bjnano.6.143

• structural and magnetic measurements, depict that nanoparticles of the same size but different oxidation state are not in the same magnetic state at RT. This is extremely important with regards to their application. A slow heat treatment allows modification of the oxidation state, but not of the particle

Heterometal nanoparticles from Ru-based molecular clusters covalently anchored onto functionalized carbon nanotubes and nanofibers

• Deborah Vidick,
• Xiaoxing Ke,
• Michel Devillers,
• Claude Poleunis,
• Arnaud Delcorte,
• Pietro Moggi,
• Gustaaf Van Tendeloo and
• Sophie Hermans

Beilstein J. Nanotechnol. 2015, 6, 1287–1297, doi:10.3762/bjnano.6.133

• molecular mixed-metal clusters as precursors for depositing heterometal nanoparticles on carbon nanotubes and nanofibers. The advantages of such precursors are that they present well-defined molecular structures and exchangeable ligands, the metal atoms are in the zero oxidation state and bimetal

From lithium to sodium: cell chemistry of room temperature sodium–air and sodium–sulfur batteries

• Philipp Adelhelm,
• Pascal Hartmann,
• Conrad L. Bender,
• Martin Busche,
• Christine Eufinger and
• Juergen Janek

Beilstein J. Nanotechnol. 2015, 6, 1016–1055, doi:10.3762/bjnano.6.105

• one-electron transfer per formula unit. In this process, the de-/intercalation of one Li-ion is linked to a change in the transition metal oxidation state by one (Co3+/4+, Fe2+/3+, Mn3+/4+, etc.), as illustrated in Figure 2a. However, since the positive electrode materials often suffer from stability

Tm-doped TiO₂ and Tm₂Ti₂O₇ pyrochlore nanoparticles: enhancing the photocatalytic activity of rutile with a pyrochlore phase

• Desiré M. De los Santos,
• Javier Navas,
• Teresa Aguilar,
• Antonio Sánchez-Coronilla,
• Concha Fernández-Lorenzo,
• Rodrigo Alcántara,
• Jose Carlos Piñero,
• Ginesa Blanco and
• Joaquín Martín-Calleja

Beilstein J. Nanotechnol. 2015, 6, 605–616, doi:10.3762/bjnano.6.62

• values reported in the literature for Ti(IV) [26]. The FWHM of the Ti 2p3/2 peak (0.98 eV) is quite consistent with this assignment [27]. Therefore, the predominant oxidation state for Ti in our samples was assumed to be Ti4+, while the presence of Ti3+ in TiO2 [28] was negligible. The BE for Tm 4d5/2 in

Overview of nanoscale NEXAFS performed with soft X-ray microscopes

• Peter Guttmann and
• Carla Bittencourt

Beilstein J. Nanotechnol. 2015, 6, 595–604, doi:10.3762/bjnano.6.61

• NEXAFS-TXM. As a result of this investigation it was found that neither Cd nor S diffuse into the CuO phase after the deposition of CdS on the CuO nanowires [60][61]. The possibility to study the oxidation state of Mn dopants in titanate nanostructures was reported in [62]. Additionally, using the

Palladium nanoparticles anchored to anatase TiO₂ for enhanced surface plasmon resonance-stimulated, visible-light-driven photocatalytic activity

• Kah Hon Leong,
• Hong Ye Chu,
• Shaliza Ibrahim and
• Pichiah Saravanan

Beilstein J. Nanotechnol. 2015, 6, 428–437, doi:10.3762/bjnano.6.43

• deposition of Pd NPs. The decrease of BET surface area and average pore diameter was due to a minor blocking of the pores in anatase TiO2 by the deposited Pd NPs [48]. In order to determine the chemical composition and oxidation state of the prepared photocatalysts, X-ray photoelectron spectroscopy (XPS) was

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

• = 1020 K, is shown. In the spectrum it is possible to observe features from both Ce3+ and Ce4+ ionic species, as already observed for ceria NPs. In fact a core–shell model was proposed [24][25] for the oxidation state of the CeO2−x NPs, which assumes that the core of the nanoparticle is composed of CeO2

• exposure for every value of the X-ray source operating power, in order to detect if the longer exposure affected the oxidation state. Fit results are shown in Figure 4b. Five different power values have been used: 40 W, 100 W, 150 W, 200 W, 270 W, the last one being the one that was used conventionally to

• NPs have been investigated and it was demonstrated that the concentration of Ce3+ ions decreases as a function of particle size for this kind of synthesis method. We investigated in detail how the combination of X-ray power, exposure and UHV conditions influence the oxidation state of the NPs and

Manganese oxide phases and morphologies: A study on calcination temperature and atmospheric dependence

• Matthias Augustin,
• Daniela Fenske,
• Ingo Bardenhagen,
• Anne Westphal,
• Martin Knipper,
• Thorsten Plaggenborg,
• Joanna Kolny-Olesiak and
• Jürgen Parisi

Beilstein J. Nanotechnol. 2015, 6, 47–59, doi:10.3762/bjnano.6.6

• such as particle size, surface area and Mnx+ oxidation state is required. Here, Mn3O4 and Mn5O8 nanoparticles as well as mesoporous α-Mn2O3 particles were synthesized by calcination of Mn(II) glycolate nanoparticles obtained through an economical route based on a polyol synthesis. The preparation of

• ) glycolate particles were calcined for 2 h in Ar and O2 atmospheres at different temperatures between 320 and 550 °C to investigate the dependence of the particle size, their morphology and the Mnx+ oxidation state in the resulting manganese oxide on the calcination temperature and atmosphere. The X-ray

Synthesis and characterization of fluorescence-labelled silica core-shell and noble metal-decorated ceria nanoparticles

• Rudolf Herrmann,
• Markus Rennhak and
• Armin Reller

Beilstein J. Nanotechnol. 2014, 5, 2413–2423, doi:10.3762/bjnano.5.251

• -made. Their principal application is for catalysis. Due to the easy change of the oxidation state (Ce(III) and Ce(IV)) they can act as redox catalysts themselves, e.g., for the regulation of combustion and many other applications [29][30]. Even more important is their use as carrier material for

UHV deposition and characterization of a mononuclear iron(III) β-diketonate complex on Au(111)

• Irene Cimatti,
• Silviya Ninova,
• Valeria Lanzilotto,
• Luigi Malavolti,
• Luca Rigamonti,
• Brunetto Cortigiani,
• Matteo Mannini,
• Elena Magnano,
• Federica Bondino,
• Federico Totti,
• Andrea Cornia and
• Roberta Sessoli

Beilstein J. Nanotechnol. 2014, 5, 2139–2148, doi:10.3762/bjnano.5.223

• . As for the Fe 2p region, the signal is detectable but quite noisy at saturation coverage, and practically negligible at t1. Therefore, no useful information about the Fe oxidation state could be retrieved. STM and DFT characterization Spectroscopic characterization indicates that Fe(dpm)3 adsorbs on

Towards bottom-up nanopatterning of Prussian blue analogues

• Virgile Trannoy,
• Marco Faustini,
• David Grosso,
• Sandra Mazerat,
• François Brisset,
• Alexandre Dazzi and
• Anne Bleuzen

Beilstein J. Nanotechnol. 2014, 5, 1933–1943, doi:10.3762/bjnano.5.204

• investigation Infrared spectroscopy, and especially the ν(C≡N) vibration band located in the spectral range of 2100–2200 cm−1 is usually used to characterize PBA species. Indeed, the cyanide bridge is extremely sensitive to its environment, including the oxidation state and the spin state of the transition

Quasi-1D physics in metal-organic frameworks: MIL-47(V) from first principles

• Danny E. P. Vanpoucke,
• Jan W. Jaeken,
• Stijn De Baerdemacker,
• Kurt Lejaeghere and
• Veronique Van Speybroeck

Beilstein J. Nanotechnol. 2014, 5, 1738–1748, doi:10.3762/bjnano.5.184

• ferromagnetic chains, respectively. This shows that the same oxidation state is present in both cases. Comparison to V charges in MIL-47(V) MOFs with functionalized linkers shows exactly the same charge, indicative of a +IV oxidation state [22]. Note that, as is to be expected from Hirshfeld-I charges, these

• (≈0.9 μB) than in the antiferromagnetic chains (≈0.8 μB). However, both are indicative of a V4+ oxidation state. Interestingly, all O atoms in the vanadyl chains also show a small magnetization (0.06 and 0.08 μB in the antiferromagnetic and ferromagnetic chain, respectively) with a sign opposite to that

Non-covalent and reversible functionalization of carbon nanotubes

• Antonello Di Crescenzo,
• Valeria Ettorre and
• Antonella Fontana

Beilstein J. Nanotechnol. 2014, 5, 1675–1690, doi:10.3762/bjnano.5.178

• dispersion. The precipitation of SWCNTs is induced by reduction of newly formed disulfide bonds. Other experimental evidences have been reported on reversible nanotube dispersion via modulation of the oxidation state of a metal complex used as the dispersant. Nobusawa et al. demonstrated how the addition of

Current state of laser synthesis of metal and alloy nanoparticles as ligand-free reference materials for nano-toxicological assays

• Christoph Rehbock,
• Jurij Jakobi,
• Lisa Gamrad,
• Selina van der Meer,
• Daniela Tiedemann,
• Ulrike Taylor,
• Wilfried Kues,
• Detlef Rath and
• Stephan Barcikowski

Beilstein J. Nanotechnol. 2014, 5, 1523–1541, doi:10.3762/bjnano.5.165

• . These processes are favored by crystal defects, UV light activation and composition and oxidation state of the surface of the nanoparticle. Hence toxicity of nanoparticles may be dominated by its catalytic activity at the nano–bio interface [36]. Even though these findings were predominantly applied for

• a systematic evaluation of adverse effects of less noble metals and metal oxide nanoparticles [154], their applicability to AuAg alloys may still be possible. The driving forces in this context were identified to be the surface potential and oxidation state of the nanoparticles, both potentially

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