Alloyed Pt₃M (M = Co, Ni) nanoparticles supported on S- and N-doped carbon nanotubes for the oxygen reduction reaction

• Stéphane Louisia,
• Yohann R. J. Thomas,
• Pierre Lecante,
• Marie Heitzmann,
• M. Rosa Axet,
• Pierre-André Jacques and
• Philippe Serp

Beilstein J. Nanotechnol. 2019, 10, 1251–1269, doi:10.3762/bjnano.10.125

• nanoparticles, on the preparation of the catalytic layer, and on the electrocatalytic performance in the ORR. On N-CNT supports, the specific activity followed the expected order Pt3Co > Pt3Ni, whereas on the annealed N-CNT support, the order was reversed. Keywords: carbon nanotubes; cobalt; ionic liquid

• cobalt and nickel salts. The HRTEM images of Co/N-CNT samples are depicted in Figure 6a,b. First, no residual IL can be observed. Surprisingly, despite a high cobalt loading (52% w/w), Co NPs were also not observed on the surface of the N-CNTs. Instead, Co atoms (Figure 6a,b) and a few non-crystallized

• selected area) displaying a Pt3Co composition. The absence of Co NPs in the Co/N-CNT sample, and the composition and structure of the Pt3Co/N-CNTs, indicate that the Pt3Co/N-CNT is more likely an alloy than a core–shell structure. The presence of residual cobalt atoms or clusters on the CNT surface was

Tailoring the magnetic properties of cobalt ferrite nanoparticles using the polyol process

• Malek Bibani,
• Romain Breitwieser,
• Alex Aubert,
• Vincent Loyau,
• Silvana Mercone,
• Souad Ammar and
• Fayna Mammeri

Beilstein J. Nanotechnol. 2019, 10, 1166–1176, doi:10.3762/bjnano.10.116

• magnetic nanoparticles (NPs) must be highly magnetostrictive and magnetically blocked at room temperature despite their nanometer-size. We describe here the use of the polyol process to synthesize cobalt ferrite (CoxFe3−xO4) nanoparticles with controlled size and composition and the study of the

• while the sub-stoichiometric NPs (particularly for x ≈ 0.7) are expected to be less magnetostrictive but to present a higher magnetocrystalline anisotropy constant, as previously observed in bulk cobalt ferrites. To control the size of the NPs, in order to overcome the superparamagnetic limit, as well

• piezoelectric polymers. Keywords: cobalt ferrite; magnetocrystalline anisotropy; magnetostriction; nanoparticle; non-stoichiometry; polyol process; Introduction Recently, extrinsically (or artificially) magnetoelectric (ME) multiferroic (MF) materials have been seriously investigated for many applications in

Concurrent nanoscale surface etching and SnO₂ loading of carbon fibers for vanadium ion redox enhancement

• Jun Maruyama,
• Shohei Maruyama,
• Tomoko Fukuhara,
• Toru Nagaoka and
• Kei Hanafusa

Beilstein J. Nanotechnol. 2019, 10, 985–992, doi:10.3762/bjnano.10.99

• redox flow batteries (VRFBs), which are in the most advanced stage of research and development: Nanoscale surface etching was attained by coating the surface with a carbonaceous thin film derived from cobalt(II) phthalocyanine (CoPc) and subsequent thermal oxidation followed by acid washing. The

Co-doped MnFe₂O₄ nanoparticles: magnetic anisotropy and interparticle interactions

• Bagher Aslibeiki,
• Parviz Kameli,
• Hadi Salamati,
• Giorgio Concas,
• Maria Salvador Fernandez,
• Alessandro Talone,
• Giuseppe Muscas and
• Davide Peddis

Beilstein J. Nanotechnol. 2019, 10, 856–865, doi:10.3762/bjnano.10.86

• Struttura della Materia-CNR, 00015 Monterotondo Scalo (RM), Italy Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala, Sweden Department of Chemistry and Industrial Chemistry (DCIC), University of Genova, Genova, Italy 10.3762/bjnano.10.86 Abstract The effect of cobalt

• . Keywords: cobalt doping; collective dynamics; ferrite nanoparticles; interparticle interactions; magnetic properties; Introduction A strong scientific interest has driven the fundamental research on magnetic nanoparticles in the last decades [1][2][3][4], with interest constantly fed by their wide range

• different magnetic anisotropy opens interesting perspectives for applications in biomedical fields (e.g., MRI, drug delivery, hyperthermia) [20][21] and energy harvesting. Experimental Synthesis Several samples consisting of manganese ferrite nanoparticles with different cobalt doping, i.e., Mn1−xCoxFe2O4

Periodic Co/Nb pseudo spin valve for cryogenic memory

• Nikolay Klenov,
• Yury Khaydukov,
• Sergey Bakurskiy,
• Roman Morari,
• Igor Soloviev,
• Vladimir Boian,
• Thomas Keller,
• Mikhail Kupriyanov,
• Anatoli Sidorenko and
• Bernhard Keimer

Beilstein J. Nanotechnol. 2019, 10, 833–839, doi:10.3762/bjnano.10.83

• )/Co(2.5 nm)/Nb(8 nm)]6/Co(1.5 nm)/Nb(25 nm) structure. We took niobium as a superconducting material since it has the highest TC = 9.25 K among all elemental superconductors and forms stable structures with cobalt [19][26][27][28][29][30]. The thickness of the Nb-spacer was chosen to be close to ξS

Renewable energy conversion using nano- and microstructured materials

• Harry Mönig and
• Martina Schmid

Beilstein J. Nanotechnol. 2019, 10, 771–773, doi:10.3762/bjnano.10.76

• in nanoporous cobalt oxide photocathodes [7], and an approach in which silicon nanoparticles are embedded in an amorphous carbon matrix [8]. In terms of material saving, nano- and microstructured absorbers offer great potential, e.g., via ultrathin absorbers as highlighted for Sb2S3 hybrid solar

The effect of translation on the binding energy for transition-metal porphyrines adsorbed on Ag(111) surface

• Luiza Buimaga-Iarinca and
• Cristian Morari

Beilstein J. Nanotechnol. 2019, 10, 706–717, doi:10.3762/bjnano.10.70

• be used to achieve similar effects [74][75]. It was shown that chemical bonds formed between substrate and molecule may lead to a deformation of the planar structure of the Co-porphyrine or Co-phthalocyanine resulting in the increase of the molecule–cobalt distance up to 0.8 Å [75]. Our data also

Zn/F-doped tin oxide nanoparticles synthesized by laser pyrolysis: structural and optical properties

• Florian Dumitrache,
• Iuliana P. Morjan,
• Elena Dutu,
• Ion Morjan,
• Claudiu Teodor Fleaca,
• Monica Scarisoreanu,
• Alina Ilie,
• Marius Dumitru,
• Cristian Mihailescu,
• Adriana Smarandache and
• Gabriel Prodan

Beilstein J. Nanotechnol. 2019, 10, 9–21, doi:10.3762/bjnano.10.2

• solutions [13] and iv.) iron by laser pyrolysis [14][15] or by electron beam evaporation [16]. Cobalt-doped tin oxide has also been reported, and the resulting polycrystalline films were prepared by spin-coating and annealing from chloride ethanolic solutions resulted in lower bandgap values than pure SnO2

Electrolyte tuning in dye-sensitized solar cells with N-heterocyclic carbene (NHC) iron(II) sensitizers

• Mariia Karpacheva,
• Catherine E. Housecroft and
• Edwin C. Constable

Beilstein J. Nanotechnol. 2018, 9, 3069–3078, doi:10.3762/bjnano.9.285

• the first row d-block metals, iron, cobalt, nickel, copper and zinc have Earth-crustal abundances of ≈41,000, 20, 80, 50 and 75 ppm, respectively. We and others [16][17][18][19] have realized the potential of DSCs sensitized by bis(diimine)copper(I) complexes, and both we [20] and Dragonetti et al

Hydrogen-induced plasticity in nanoporous palladium

• Markus Gößler,
• Eva-Maria Steyskal,
• Markus Stütz,
• Norbert Enzinger and
• Roland Würschum

Beilstein J. Nanotechnol. 2018, 9, 3013–3024, doi:10.3762/bjnano.9.280

• ]. Dealloying was stopped at currents below 0.1 mA. The residual cobalt concentration in nanoporous palladium prepared via this route was reported to be below 2 atom % [58]. Electrochemical cell setup After dealloying, the samples were rinsed in distilled water for several minutes, before immersing them in 1 M

Graphene-enhanced metal oxide gas sensors at room temperature: a review

• Dongjin Sun,
• Yifan Luo,
• Marc Debliquy and
• Chao Zhang

Beilstein J. Nanotechnol. 2018, 9, 2832–2844, doi:10.3762/bjnano.9.264

• achieved at all [19][20]. Metal-oxide semiconductors (MOS), including tin oxide (SnO2), titanium dioxide (TiO2), zinc oxide (ZnO), copper oxide (CuO), tungsten oxide (WO3), indium oxide (In2O3), ferric oxide (Fe2O3) and cobalt oxide (Co3O4) are important materials for gas sensors [21][22][23][24][25][26

Nanocellulose: Recent advances and its prospects in environmental remediation

• Katrina Pui Yee Shak,
• Yean Ling Pang and
• Shee Keat Mah

Beilstein J. Nanotechnol. 2018, 9, 2479–2498, doi:10.3762/bjnano.9.232

• multiple carboxy functional groups for the adsorption of uranium(VI) and cobalt(II). The co-polymerization of itaconic acid and methacrylic acid was able to introduce three carboxy functionalities which increased reactivity and hydrophilicity for effective removal of the metal ions from the aqueous

• (itaconic acid)–poly(methacrylic acid)-grafted-nanocellulose/nanobentonite composite as an efficient adsorbent for the removal of cobalt (Co(II)) from aqueous solution. This could increase the availability of the multi-carboxy functional moiety, which is covalently bonded to the inorganic matrix, to

Thickness-dependent photoelectrochemical properties of a semitransparent Co₃O₄ photocathode

• Malkeshkumar Patel and
• Joondong Kim

Beilstein J. Nanotechnol. 2018, 9, 2432–2442, doi:10.3762/bjnano.9.228

• indicating the stoichiometric ratio of 1:2. We propose that a semitransparent Co3O4 photoactive electrode is a prospective candidate for use in PEC cells via heterojunctions for hydrogen generation. Keywords: cobalt(II,III) oxide (Co3O4); photocathode; photoelectrochemical cells; semitransparent; thickness

• octahedral (Co3+) and tetrahedral (Co2+) cobalt sites, where Co vacancies are the dominant sources of the p-type conductivity of Co3O4 under oxygen-rich conditions [9][13]. Despite these interesting properties of Co3O4 its application in photocathodes has been rarely studied [18][19][20][21][22][23

ZnO-nanostructure-based electrochemical sensor: Effect of nanostructure morphology on the sensing of heavy metal ions

• Marina Krasovska,
• Vjaceslavs Gerbreders,
• Irena Mihailova,
• Andrejs Ogurcovs,
• Eriks Sledevskis,
• Andrejs Gerbreders and
• Pavels Sarajevs

Beilstein J. Nanotechnol. 2018, 9, 2421–2431, doi:10.3762/bjnano.9.227

• lead, mercury, cadmium and cobalt, are becoming more and more topical. Many metals form stable organic compounds that dissolve well in water and result in the migration of heavy metal ions in aquatic and terrestrial systems, thereby resulting in high levels of contamination [1][2]. Lead is one of the

Hydrothermal-derived carbon as a stabilizing matrix for improved cycling performance of silicon-based anodes for lithium-ion full cells

• Mirco Ruttert,
• Florian Holtstiege,
• Jessica Hüsker,
• Markus Börner,
• Martin Winter and
• Tobias Placke

Beilstein J. Nanotechnol. 2018, 9, 2381–2395, doi:10.3762/bjnano.9.223

• containing the synthesized materials were used as working electrodes (WE), while lithium metal (Li; Albemarle Corporation) was used as counter and reference (RE) electrodes. In the full cell set-up, the Si/C composite electrodes were cycled vs lithium nickel manganese cobalt oxide (LiNi1/3Mn1/3Co1/3O2, NMC

Block copolymers for designing nanostructured porous coatings

• Roberto Nisticò

Beilstein J. Nanotechnol. 2018, 9, 2332–2344, doi:10.3762/bjnano.9.218

• leaving the PEO domains visible (and forming a porous structure). Analogous results were also obtained for cobalt onto PS-b-PEO [100]. Concerning the soft-templating route, usually the most diffuse porogens used are surfactants: small molecules characterized by having both polar (head) and apolar (tail

Metal-free catalysis based on nitrogen-doped carbon nanomaterials: a photoelectron spectroscopy point of view

• Mattia Scardamaglia and
• Carla Bittencourt

Beilstein J. Nanotechnol. 2018, 9, 2015–2031, doi:10.3762/bjnano.9.191

• the π-system of pyridinic N and graphene, as already reported for carbon nanofibers by Maldonado and Stevenson [102]. A more detailed study was performed by Kundu et al. [103] on N-CNTs prepared via pyrolysis of acetonitrile over cobalt catalysts. Samples were synthesized at different temperatures

Synthesis of hafnium nanoparticles and hafnium nanoparticle films by gas condensation and energetic deposition

• Irini Michelakaki,
• Nikos Boukos,
• Dimitrios A. Dragatogiannis,
• Spyros Stathopoulos,
• Costas A. Charitidis and
• Dimitris Tsoukalas

Beilstein J. Nanotechnol. 2018, 9, 1868–1880, doi:10.3762/bjnano.9.179

• demonstrate high catalytic activity during hydrogenation of levulinic acid [17], nickel NPs, which find application as electrochemical sensor [18], and cobalt NPs, which exhibit high magnetic anisotropy [19]. Recently, we have reported that hcp hafnium nanoparticles fabricated by inert-gas condensation, when

Uniform cobalt nanoparticles embedded in hexagonal mesoporous nanoplates as a magnetically separable, recyclable adsorbent

• Can Zhao,
• Yuexiao Song,
• Tianyu Xiang,
• Wenxiu Qu,
• Shuo Lou,
• Xiaohong Yin and
• Feng Xin

Beilstein J. Nanotechnol. 2018, 9, 1770–1781, doi:10.3762/bjnano.9.168

• (LDH). A uniform PDA coating initially covers the surface of LDH by dopamine self-polymerization under mild conditions. Well-dispersed Co nanoparticles are formed in the NPLs by the partial reduction of cobalt from Co2+ to Co0 with surface carbon during the heat treatment process. The surface

• in the carbon layer; and (iv) the obtained hexagonal magnetic mesoporous NPL displays a larger adsorption capacity towards removal of RhB from water than observed in other adsorbents [23][24][25][26][27][28][29][30]. Experimental Materials and chemicals Cobalt chloride hexahydrate, aluminum chloride

• containing magnetic Co nanoparticles (CoAl2O4 phase) and porous carbon layer by partial reduction Co2+ ions in the lattice of LDH with carbon during carbonization process at 800 °C [15][34]. The Z-contrast image in HAADF-STEM image correlates strongly with the atomic mass. Metallic cobalt is a heavier

Interaction-tailored organization of large-area colloidal assemblies

• Silvia Rizzato,
• Elisabetta Primiceri,
• Anna Grazia Monteduro,
• Adriano Colombelli,
• Angelo Leo,
• Maria Grazia Manera,
• Roberto Rella and
• Giuseppe Maruccio

Beilstein J. Nanotechnol. 2018, 9, 1582–1593, doi:10.3762/bjnano.9.150

• or L, indicating small or large spheres, respectively, upper index refers to the NaCl concentration, and the lower index indicates the particle concentration in wt %. After colloidal assembly of the polystyrene particles, gold and cobalt nanohole arrays (Figure 1b) were realized by depositing 20 nm

• thick metal layers (gold films deposited by thermal evaporation and cobalt films deposited by magnetron sputtering) and successively removing the metal-capped spherical, nanoscale materials (termed “nanospheres” throughout the remainder of this article) by careful tape stripping with carbon tape in

• properties of cobalt nanoholes were investigated by the magneto-optical Kerr effect technique in longitudinal configuration. The samples were placed between the poles of a GMW 3470 electromagnet, where the magnetic field intensity was measured by a Group3 Teslameter probe. A He–Ne laser beam (wavelength 633

Chemistry for electron-induced nanofabrication

• Petra Swiderek,
• Hubertus Marbach and
• Cornelis W. Hagen

Beilstein J. Nanotechnol. 2018, 9, 1317–1320, doi:10.3762/bjnano.9.124

• precursor, thus highlighting the importance of the actual chemical nature of the substrate [31]. This Thematic Series is completed by publications on interesting applications of FEBID. This concerns the fabrication and characterization of magnetic cobalt nanospheres on cantilever tips for magnetic resonance

Heterostuctures of 4-(chloromethyl)phenyltrichlorosilane and 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine prepared on Si(111) using particle lithography: Nanoscale characterization of the main steps of nanopatterning

• Phillip C. Chambers and
• Jayne C. Garno

Beilstein J. Nanotechnol. 2018, 9, 1211–1219, doi:10.3762/bjnano.9.112

• differences in structure and conformation [15]. The submolecular structure of cobalt and copper phthalocyanines on gold substrates were resolved with STM by Lu et al. [16]. The differences in central metals were resolved for a mixed sample. The molecular orientation and molecular switching properties of a

Magnetic characterization of cobalt nanowires and square nanorings fabricated by focused electron beam induced deposition

• Federico Venturi,
• Gian Carlo Gazzadi,
• Amir H. Tavabi,
• Alberto Rota,
• Rafal E. Dunin-Borkowski and
• Stefano Frabboni

Beilstein J. Nanotechnol. 2018, 9, 1040–1049, doi:10.3762/bjnano.9.97

Towards the third dimension in direct electron beam writing of silver

• Katja Höflich,
• Jakub Mateusz Jurczyk,
• Katarzyna Madajska,
• Maximilian Götz,
• Luisa Berger,
• Carlos Guerra-Nuñez,
• Caspar Haverkamp,
• Iwona Szymanska and
• Ivo Utke

Beilstein J. Nanotechnol. 2018, 9, 842–849, doi:10.3762/bjnano.9.78

• of the purity of Co–C nanopillars on the growth pressure in cobalt deposition and provided strong hints that indeed a small precursor flux can trigger higher purity but also broader geometrical features [29]. For applications in plasmonics elemental silver is crucial. Here, surface-enhanced Raman

Heavy-metal detectors based on modified ferrite nanoparticles

• Urszula Klekotka,
• Ewelina Wińska,
• Elżbieta Zambrzycka-Szelewa,
• Dariusz Satuła and
• Beata Kalska-Szostko

Beilstein J. Nanotechnol. 2018, 9, 762–770, doi:10.3762/bjnano.9.69

• Abstract In this work, we analyze artificial heavy-metal solutions with ferrite nanoparticles. Measurements of adsorption effectiveness of different kinds of particles, pure magnetite or magnetite doped with calcium, cobalt, manganese, or nickel ions, were carried out. A dependence of the adsorption

• , for example such as linker concentration, heavy ions concentration, pH value, or inorganic core composition, and such studies are in progress and will be a subject of subsequent papers. Conclusion Ferrite nanoparticles doped with calcium, cobalt, nickel, or manganese show differences in ion adsorption