Widening of the electroactivity potential range by composite formation – capacitive properties of TiO₂/BiVO₄/PEDOT:PSS electrodes in contact with an aqueous electrolyte

• Konrad Trzciński,
• Mariusz Szkoda,
• Andrzej P. Nowak,
• Marcin Łapiński and
• Anna Lisowska-Oleksiak

Beilstein J. Nanotechnol. 2019, 10, 483–493, doi:10.3762/bjnano.10.49

• charged and discharged over a wide potential range. Both electrical double-layer capacitance and faradaic reactions can contribute to the final capacitance of an electrode. Many different materials have been tested as electrode materials for supercapacitors, such as metal oxides [6][7][8], carbon

Nanocomposite–parylene C thin films with high dielectric constant and low losses for future organic electronic devices

• Marwa Mokni,
• Gianluigi Maggioni,
• Abdelkader Kahouli,
• Sara M. Carturan,
• Walter Raniero and
• Alain Sylvestre

Beilstein J. Nanotechnol. 2019, 10, 428–441, doi:10.3762/bjnano.10.42

• increase the X-ray incidence angle to 1.0° in order to probe all the film thickness and highlight the Ag oxides crystalline peaks (see Figure 3 right). The broadness of these peaks indicates that the average nanocrystallite size is small (≤5 nm), as could be expected taking into account that silver is

• shown. Asterisks indicate the peaks of Ag oxides. Si peaks coming from the substrate are also highlighted. Roughness (Ra) as a function of the thickness. The red curve is the trend for pure parylene C films obtained in [65]. FTIR spectra of pure parylene C (samples O and K) and NCPCs (samples A to F). a

Advanced scanning probe lithography using anatase-to-rutile transition to create localized TiO₂ nanorods

• Julian Kalb,
• Vanessa Knittel and
• Lukas Schmidt-Mende

Beilstein J. Nanotechnol. 2019, 10, 412–418, doi:10.3762/bjnano.10.40

• nanostructures. Keywords: hydrothermal crystal growth; lithography; nanostructures; seed crystals; surface processes; oxides; Introduction Rutile TiO2 is a chemically stable semiconductor with a band gap of 3.1 eV [1]. Dependent on the kind of nanostructure and doping, it has outstanding electronic and

Sub-wavelength waveguide properties of 1D and surface-functionalized SnO₂ nanostructures of various morphologies

• Venkataramana Bonu,
• Binaya Kumar Sahu,
• Arindam Das,
• Sankarakumar Amirthapandian,
• Sandip Dhara and
• Harish C. Barshilia

Beilstein J. Nanotechnol. 2019, 10, 379–388, doi:10.3762/bjnano.10.37

• light during the medical process. Among metal oxides, SnO2 NWs, an n-type direct wide-band semiconductor (Eg = 3.6 eV at 300 K), was proved to be excellent sub-wavelength waveguide [3][4][5][6][7][12]. The high refractive index (n = 2.1) of SnO2 allows NWs with an optimal size range (100 to 500 nm) to

• nanoparticles [18] have been reported in our previous studies. We have also deciphered strong correlations of various defects in SnO2 NSs for chemical gas sensing [13] and wettability properties [19]. The growth of metal oxides with controllable dimensions is an important area for technological applications. In

• , which matches closely with our experimental results. Optical properties Waveguide nature SnO2 NBs have been shown to be very good sub-wavelength waveguides among the metal oxides [6][12]. Figure 6 and Figure 7 depict optical images of the single SnO2 NWs demonstrating their waveguide behaviour. Similar

One-step nonhydrolytic sol–gel synthesis of mesoporous TiO₂ phosphonate hybrid materials

• Yanhui Wang,
• P. Hubert Mutin and
• Johan G. Alauzun

Beilstein J. Nanotechnol. 2019, 10, 356–362, doi:10.3762/bjnano.10.35

• hybrids are obtained in two steps, by surface modification of a porous metal oxide support [17][18][19]. Nonhydrolytic (or nonaqueous) sol–gel (NHSG) chemistry has provided simple and powerful routes to synthesize oxides or mixed oxides with different morphologies (e.g., nanoparticles) or textures (e.g

• with 1,3,5-trihydroxybenzene [32]. The reaction of alkoxides in acetophenone (used as a solvent and an oxygen donor) has already been described for the synthesis of TiO2 [33] and BaTiO3 [34] nanoparticles, but it has never been used to prepare mesoporous oxides or hybrid materials. In the present work

A Ni(OH)₂ nanopetals network for high-performance supercapacitors synthesized by immersing Ni nanofoam in water

• Donghui Zheng,
• Man Li,
• Yongyan Li,
• Chunling Qin,
• Yichao Wang and
• Zhifeng Wang

Beilstein J. Nanotechnol. 2019, 10, 281–293, doi:10.3762/bjnano.10.27

• between active materials and electrolyte, for which transition metal oxides/hydroxides with multiple valence are used as electrode materials [8][9]. EDLCs hold a high power density and long cycling stability, but their practical application is limited by the low energy density. In comparison, pseudo

• -capacitors possess a higher energy density and are regarded as promising candidates for energy storage systems [10]. Among the various transition metal oxides/hydroxides, Ni(OH)2 is an ideal candidate for pseudo-capacitors due to its unique features such as high theoretical capacity and outstanding redox

• mainly consists of Ti4+ and Zr4+ oxides. On the other hand, Figure 4d and Figure 4e reveal the Ni 2p3/2 and O 1s peaks obtained from the as-spun alloy and as-dealloyed alloy before and after immersion in deionized water. The O 1s region analyzed by using a Gaussian fitting method (Figure 4e) shows three

Thermal control of the defunctionalization of supported Au₂₅(glutathione)₁₈ catalysts for benzyl alcohol oxidation

• Zahraa Shahin,
• Hyewon Ji,
• Rodica Chiriac,
• Nadine Essayem,
• Franck Rataboul and
• Aude Demessence

Beilstein J. Nanotechnol. 2019, 10, 228–237, doi:10.3762/bjnano.10.21

• nanoparticles (GNPs), GNPs have been of great interest in chemistry, dispersed on metal oxides and in CO oxidation reaction [1]. Today, GNPs of diameter less than 10 nm are known to be a remarkable, heterogeneous catalyst, capable of catalyzing a wide range of reactions including hydrocarbon combustion [2

Nanoporous water oxidation electrodes with a low loading of laser-deposited Ru/C exhibit enhanced corrosion stability

• Sandra Haschke,
• Dmitrii Pankin,
• Vladimir Mikhailovskii,
• Maïssa K. S. Barr,
• Adriana Both-Engel,
• Alina Manshina and
• Julien Bachmann

Beilstein J. Nanotechnol. 2019, 10, 157–167, doi:10.3762/bjnano.10.15

• limited by its significant dissolution (corrosion) at high anodic potential over the whole pH range (Figure 2) [10][11][12]. One strategy to address this limitation has involved mixing metallic Ru (or its oxides) with other solids (such as Ir [13][14][15][16][17][18], Ta [19], or Pt [20], TiO2 [21], Ni

• to never exceed +1.0 V applied potential. On the cathodic scan, only one reductive peak is present near 0.0 V, corresponding to the reduction of surface oxides to metallic Ru [68]. The absence of surface oxidization current during the first CV cycle (blue curve in Figure 9a) indicates that the

Wet chemistry route for the decoration of carbon nanotubes with iron oxide nanoparticles for gas sensing

• Hussam M. Elnabawy,
• Juan Casanova-Chafer,
• Badawi Anis,
• Mostafa Fedawy,
• Mattia Scardamaglia,
• Carla Bittencourt,
• Ahmed S. G. Khalil,
• Eduard Llobet and
• Xavier Vilanova

Beilstein J. Nanotechnol. 2019, 10, 105–118, doi:10.3762/bjnano.10.10

• into more reactive species that, in turn, interact with CNTs. In addition, such nanoparticles shift the Fermi level of CNTs, adsorb target molecules, and help in mediating the charge transfer between adsorbates and CNTs [6][10]. Several metal oxides have been reported as useful for decorating CNTs and

• improving their interaction with gas molecules. Sensitivity and selectivity can be tailored by selecting the type of metal oxide employed, the size of nanoparticles and the decoration density or loading [6][10][11]. Metal oxides have been extensively investigated for sensing a wide range of gases [12][13

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

• dopant concentration). Keywords: laser pyrolysis; nanoparticles; optical bandgap; Zn/F-doped SnO2; Introduction Recently, there has been growing interest in the field of transparent conducting oxides and wide bandgap oxide nanocrystalline materials such as tin oxide (SnO2). It is generally agreed that

• reduced bandgap of tin oxide nanoparticles by introduction of defects to the crystal lattice is ≈0.7 eV [4]. Generally, the doping of these semiconducting oxides with specific cations or anions is performed in order to increase their electrical conductivity while maintaining a high optical transparency in

• precursors to oxides (SnO2 and ZnO, in fact Zn-doped SnO2), CO2 and H2O in the laser pyrolysis reaction zone. Due to the much higher reactivity of metals, the metal oxides are formed with priority, and the unoxidized alkyl radicals from the precursors will undergo a complex process involving reactions such

A novel polyhedral oligomeric silsesquioxane-modified layered double hydroxide: preparation, characterization and properties

• Xianwei Zhang,
• Zhongzhu Ma,
• Hong Fan,
• Carla Bittencourt,
• Jintao Wan and
• Philippe Dubois

Beilstein J. Nanotechnol. 2018, 9, 3053–3068, doi:10.3762/bjnano.9.284

• structure of LDH layers was completely destroyed by dehydroxylation, resulting in the formation of random stacking of mixed oxides containing Mg and Al [34]. The surface after degradation in air seems not as rough and coarse as that after degradation in N2, which might be caused by the different gas release

• reacts with the metal oxides to form a continuous and compact condensed phase. This mixed carbonized protecting layer provides a good barrier to the transfer of heat and mass, preventing the inner layer against further decomposition and accelerating the formation of char. Evidence in favor of this

Ternary nanocomposites of reduced graphene oxide, polyaniline and hexaniobate: hierarchical architecture and high polaron formation

• Claudio H. B. Silva,
• Maria Iliut,
• Christopher Muryn,
• Christian Berger,
• Zachary Coldrick,
• Vera R. L. Constantino,
• Marcia L. A. Temperini and
• Aravind Vijayaraghavan

Beilstein J. Nanotechnol. 2018, 9, 2936–2946, doi:10.3762/bjnano.9.272

• properties when compared to individual phases or enable new technological applications [1][2][3]. For instance, ternary nanocomposites (conducting polymers, metal oxides and carbon-based materials) exhibit improved energy and power densities, improved stabilities upon charge/discharge cycles [4], and higher

Time-resolved universal temperature measurements using NaYF₄:Er³⁺,Yb³⁺ upconverting nanoparticles in an electrospray jet

• Kristina Shrestha,
• Arwa A. Alaulamie,
• Ali Rafiei Miandashti and
• Hugh H. Richardson

Beilstein J. Nanotechnol. 2018, 9, 2916–2924, doi:10.3762/bjnano.9.270

• . Experimental Synthesis of NaYF4:Er3+,Yb3+ upconverting nanoparticles The UNCPs were synthesized using the thermal decomposition method. Briefly, sodium trifluoroacetate was added to a mixture of oxides of ytterbium, yttrium, and erbium and decomposed in oleic acid and octadecane solvent. UNCPs synthesized were

Nanostructure-induced performance degradation of WO₃·nH₂O for energy conversion and storage devices

• Zhenyin Hai,
• Mohammad Karbalaei Akbari,
• Zihan Wei,
• Danfeng Cui,
• Chenyang Xue,
• Hongyan Xu,
• Philippe M. Heynderickx,
• Francis Verpoort and
• Serge Zhuiykov

Beilstein J. Nanotechnol. 2018, 9, 2845–2854, doi:10.3762/bjnano.9.265

• layered transition metal oxides. Keywords: 2D layered oxides; interlayer water; van der Waals interaction; WO3·nH2O; Introduction Within the less than 20 years since the successful exfoliation of atomically thin graphene, 2D layered nanomaterials have been contributing greatly to the advances of

• nanoscience and nanotechnology with their exotic properties and versatility of applications [1][2][3][4][5][6][7][8][9][10]. Among all 2D nanomaterials, 2D transition metal oxides (TMOs) are the group with the highest electrochemical activities for energy conversion and storage [11][12][13][14][15]. As the

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

• sensors based on rGO/metal oxides, which exhibit enhanced sensing performance mainly due to the formation of heterojunctions. Tai et al. [46] deposited ZnO nanoparticles and GO thin films on gold interdigital electrodes (IDEs) through a simple spray process and thermally reduced the deposits to ZnO–rGO

• during the carbothermal reduction (1150 °C). Another was the formation of Schottky barriers between ZnO and the metal electrodes, which caused ZnO to exhibit p-type semiconductor properties. The gas-sensing performance parameters of the abovementioned sensors for reducing gases based on metal oxides and

• performance of the ternary composite sensor was still the p–n heterojunctions. The gas-sensing performance parameters of the abovementioned NO2 sensors based on metal oxides and rGO enhanced by the formation of semiconductor interfaces are listed in Table 2. Enhancement by improved morphology and structure By

Pattern generation for direct-write three-dimensional nanoscale structures via focused electron beam induced deposition

• Lukas Keller and
• Michael Huth

Beilstein J. Nanotechnol. 2018, 9, 2581–2598, doi:10.3762/bjnano.9.240

• ] but also various oxides and carbides in either amorphous or polycrystalline form [18][19] are accessible. By employing additional postdeposition treatments the metal volume content of some otherwise granular metals can be increased to virtually 100% [20][21][22]. Despite the apparent simplicity of the

Improved catalytic combustion of methane using CuO nanobelts with predominantly (001) surfaces

• Qingquan Kong,
• Yichun Yin,
• Bing Xue,
• Yonggang Jin,
• Wei Feng,
• Zhi-Gang Chen,
• Shi Su and
• Chenghua Sun

Beilstein J. Nanotechnol. 2018, 9, 2526–2532, doi:10.3762/bjnano.9.235

• , such as transition metal (TM) oxides and various complex structures (e.g., perovskite, spinel and hexaaluminate) have been tested as catalysts for CH4 oxidation. But so far their performance is still much lower than noble metals. An ideal catalyst for CH4 oxidation should have a high capacity to adsorb

• most metal oxides. To improve the reactivity of metal oxides, surfaces with high energy (and thus low surface area), namely minority surfaces, may offer new opportunities. Although minority surfaces often diminish quickly during crystal growth due to their low stability, they can be stabilized by

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

• -dependent properties; Introduction Hydrogen production using water splitting in photoelectrochemical (PEC) cells may help to overcome challenges in the conversion and storage of solar energy. Most of the metal oxides are earth-abundant, non-toxic, stable and easy to synthesise, and hence attractive

• -absorber materials such as metal sulfides and metal oxides via heterojunction. The photocurrent can be further improved by three approaches: The first one is to improve the optoelectronic processes in the Co3O4 film [39], the second is to improve the composition of the heterojunction, i.e. Co3O4/Ga2O3 [42

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

• mixture of lead oxides and metallic lead. The XRD pattern and EDS spectra of the sediment composition has been previously reported [16]. The formation of lead oxide is explained by the quasichemical Lewis interaction between lead ions and hydroxy groups on the ZnO surface as a result of coordination or

• to 2 mM). The reduction peak current for the highest concentration can be explained by mass crystallization in the solution, in parallel with the sorption process. It is the threshold above which crystallites of lead oxides become visible on the ZnO nanostructured surface by SEM. In order to visually

• forms well-developed crystallites of lead oxides mixture, whereas Cd(NO3)2 forms a very thin amorphous layer on the ZnO surface. The SEM images were recorded using secondary electrons, whose output depth is within the range of 1–10 nm; the fact that the contours of the ZnO nanotubes (bright points) are

Intrinsic ultrasmall nanoscale silicon turns n-/p-type with SiO₂/Si₃N₄-coating

• Dirk König,
• Daniel Hiller,
• Noël Wilck,
• Birger Berghoff,
• Merlin Müller,
• Sangeeta Thakur,
• Giovanni Di Santo,
• Luca Petaccia,
• Joachim Mayer,
• Sean Smith and
• Joachim Knoch

Beilstein J. Nanotechnol. 2018, 9, 2255–2264, doi:10.3762/bjnano.9.210

• , Si modulation doping of adjacent dielectric layers based on nitrides [11] and oxides [12], in analogy to modulation doping of III–V semiconductors, were shown to be an alternative to conventional impurity doping. It would be ideal to achieve electron- (n-) or hole- (p-) type conductivity in usn-Si

Electrospun one-dimensional nanostructures: a new horizon for gas sensing materials

• Muhammad Imran,
• Nunzio Motta and
• Mahnaz Shafiei

Beilstein J. Nanotechnol. 2018, 9, 2128–2170, doi:10.3762/bjnano.9.202

• ][22][23][24][25][26][27][28][29][30][31][32][33]. Different types of nanostructures, including those based on metal oxides (MOx), organic and inorganic materials and carbon nanostructures, have shown promising sensing performance due to their unique characteristics, such as high surface-to-volume

• shown in Figure 1. A nanofiber film has a surface area approximately twice that of a continuous thin film. This property means that nanofibers are excellent candidates for gas sensing applications. Moreover, nanofibers derived from a variety of materials, such as polymers, metals, metal-oxides and

• the development of the gas sensors employing electrospun nanofibers have been published. Recently, Choi et al. [43] reported a review on chemiresistive and optical sensors employing only semiconducting metal oxides and their functionalization by catalytic nanoparticles. Herein, we will comprehensively

Spin-coated planar Sb₂S₃ hybrid solar cells approaching 5% efficiency

• Pascal Kaienburg,
• Benjamin Klingebiel and
• Thomas Kirchartz

Beilstein J. Nanotechnol. 2018, 9, 2114–2124, doi:10.3762/bjnano.9.200

• requires the precise control of processing conditions and eventually limits the process’ reproducibility [29][32]. During chemical reactions in the water bath, various antimony oxides, hydroxides and sulfates form [6][42][43][44] which could be detrimental to device performance. With respect to oxide

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

• as platinum or its alloys, or metal oxides, which affect the engineering cost of fuel cells being also energy consuming and not highly selective [3]. Therefore, research efforts have been devoted towards alternative highly active catalysts from non-precious metals [4]. Repeatedly reported potential

Synthesis of rare-earth metal and rare-earth metal-fluoride nanoparticles in ionic liquids and propylene carbonate

• Marvin Siebels,
• Lukas Mai,
• Laura Schmolke,
• Kai Schütte,
• Juri Barthel,
• Junpei Yue,
• Jörg Thomas,
• Bernd M. Smarsly,
• Anjana Devi,
• Roland A. Fischer and
• Christoph Janiak

Beilstein J. Nanotechnol. 2018, 9, 1881–1894, doi:10.3762/bjnano.9.180

• the polymerization of olefins [15][16] and as precursors in chemical vapor (CVD) processes of rare-earth materials such as oxides and nitrides [17][18][19]. It is especially advantageous that the decomposition products from the amidinate ligand are gaseous so that product contamination is minimized

• nanoparticles were determined by transmission electron microscopy (TEM) and high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). The crystalline phases and the absence of impurities (oxides) in RE-NPs and REF3-NPs were identified by powder X-ray diffraction (PXRD) and selected

• Figures S4c, S5c, S6d, Supporting Information File 1) through comparison to the reported binding energies of metal(III) fluorides/oxides, metal(0) and organic fluorine/oxygen (Table 2) [48][49]. The measured metal and fluorine XPS values are in good agreement with the values of metal(III) fluorides that

Electrical characterization of single nanometer-wide Si fins in dense arrays

• Steven Folkersma,
• Janusz Bogdanowicz,
• Andreas Schulze,
• Paola Favia,
• Dirch H. Petersen,
• Ole Hansen,
• Henrik H. Henrichsen,
• Peter F. Nielsen,
• Lior Shiv and
• Wilfried Vandervorst

Beilstein J. Nanotechnol. 2018, 9, 1863–1867, doi:10.3762/bjnano.9.178

• voltage drop V is measured between the other two electrodes. Initially, however, the native oxides present both on the semiconducting material and the Ni-coated electrodes act as highly resistive barriers and therefore prevent any electrical contact [11]. To establish the electrical contact, the μ4pp

• contact size and the contact resistance for each electrode–fin contact are, respectively, indicated by dcontact and RCj (j = 1, 2,…, 8). Note that all contact resistances are initially considered to be highly resistive because the native oxides present on both the fins and electrodes prevent current flow