Gas sensing properties of individual SnO₂ nanowires and SnO₂ sol–gel nanocomposites

• Alexey V. Shaposhnik,
• Dmitry A. Shaposhnik,
• Sergey Yu. Turishchev,
• Olga A. Chuvenkova,
• Stanislav V. Ryabtsev,
• Alexey A. Vasiliev,
• Xavier Vilanova,
• Francisco Hernandez-Ramirez and
• Joan R. Morante

Beilstein J. Nanotechnol. 2019, 10, 1380–1390, doi:10.3762/bjnano.10.136

• , while the inner pair is used for the measurement of the electrical potential drop. This 4-electrode scheme of electrical resistance measurement improves the quality of sensor response detection. In spite of the large number of works dedicated to the use of nanowires as conductometric gas sensors, these

• energy consumption reduction of the device when using a 4-electrode connection, where the outer pair of electrodes is used for applying the electrical potential. Another feature is the ability to use silicon technology for sensing device integration with measuring circuits. This allows the fabrication of

A biomimetic nanofluidic diode based on surface-modified polymeric carbon nitride nanotubes

• Kai Xiao,
• Baris Kumru,
• Lu Chen,
• Lei Jiang,
• Bernhard V. K. J. Schmidt and
• Markus Antonietti

Beilstein J. Nanotechnol. 2019, 10, 1316–1323, doi:10.3762/bjnano.10.130

• ). The membrane was caught in a H-cell with electrolyte. A Ag/AgCl electrode was used to collect the ionic current. The I–V curves were adjusted to zero current at zero voltage to remove small offsets experienced between runs. All measurements were carried out at ambient temperature. The main

Multicomponent bionanocomposites based on clay nanoarchitectures for electrochemical devices

• Giulia Lo Dico,
• Bernd Wicklein,
• Lorenzo Lisuzzo,
• Giuseppe Lazzara,
• Pilar Aranda and
• Eduardo Ruiz-Hitzky

Beilstein J. Nanotechnol. 2019, 10, 1303–1315, doi:10.3762/bjnano.10.129

• nanofillers to ensure the mechanical strength and electrical conductivity of the prepared bionanocomposite films and foams [26]. Moreover, MWCNTs are supposed to act as nanowires improving the contact between the active site of the immobilized enzymes and an electrode surface via direct electron transfer [39

• stability of these multicomponent hybrid materials in water showing a mass loss of only 3.2 wt % over the course of two months. This excellent stability, together with the good electrical and mechanical properties, suggest that the prepared multicomponent bionanocomposite can be suitable as electrode

• fast electron transfer between the enzyme and the electrode surface. In fact, a fit of the curve with the Lineweaver–Burk plot (Figure S9, Supporting Information File 1) rendered a Michaelis–Menten constant (Km) of 9.3 mM, which is smaller than those reported for GOx in solution (33 mM) [62] and GOx

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

• reaction (ORR) have been evaluated in a rotating ring disk electrode experiment. The Pt3M/N-CNT catalysts revealed excellent electrochemical properties compared to a commercial Pt3Co/Vulcan XC-72 catalyst. The nature of the carbon support plays a key role in determining the properties of the metal

• rotating ring disk electrode (RRDE) experiment to determine the active surface and the activity for the ORR of each catalyst. Finally, membrane electrode assemblies (MEAs) of 25 cm2 active area, integrating the synthesized catalysts, have been prepared and tested. The one giving the best beginning-of-life

• selectivity In order to proceed to a first screening of the as-prepared catalysts, their electrochemical properties were evaluated by RRDE measurements. It is worth noting that electrocatalyst investigations are usually performed with a rotating ring-disk electrode (RRDE) in acidic or alkaline media. Previous

Molecular attachment to a microscope tip: inelastic tunneling, Kondo screening, and thermopower

• Rouzhaji Tuerhong,
• Mauro Boero and
• Jean-Pierre Bucher

Beilstein J. Nanotechnol. 2019, 10, 1243–1250, doi:10.3762/bjnano.10.124

• ], only the second method is used in this work. To pick up the molecule, the tip is approached above the ligand moiety. The ligand moiety is the most favorable site of binding between the phthalocyanine molecule and the sharp metallic electrode as confirmed by calculations [12]. We found that approching

Porous N- and S-doped carbon–carbon composite electrodes by soft-templating for redox flow batteries

• Maike Schnucklake,
• László Eifert,
• Jonathan Schneider,
• Roswitha Zeis and
• Christina Roth

Beilstein J. Nanotechnol. 2019, 10, 1131–1139, doi:10.3762/bjnano.10.113

• obtained inside the macroporous carbon felt. For the investigation of electrode structure and porosity X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and nitrogen sorption (BET) were used. The electrochemical performance of the carbon felts was evaluated by cyclic voltammetry

• ; porous electrode; redox flow battery; soft-templating approach; vanadium; Introduction In recent years, vanadium redox flow batteries (VRFBs) have attracted significant attention as a promising large-scale system for storing excess energy from renewable sources like wind or solar energy [1][2][3]. The

• material” in the following text (Figure 1). Structural characterization For a detailed insight into the morphology of the electrode, SEM images of the carbonized sample, N-doped carbon felt and S- and N-doped composite material were taken at two different magnifications (Figure 2). The fibers of the

Synthesis and characterization of quaternary La(Sr)S–TaS₂ misfit-layered nanotubes

• Marco Serra,
• Erumpukuthickal Ashokkumar Anumol,
• Dalit Stolovas,
• Iddo Pinkas,
• Ernesto Joselevich,
• Reshef Tenne,
• Andrey Enyashin and
• Francis Leonard Deepak

Beilstein J. Nanotechnol. 2019, 10, 1112–1124, doi:10.3762/bjnano.10.111

• open electrode front-illuminated CCD camera cooled to −60 °C (Syncerity, HORIBA, USA). The system utilizes an open confocal microscope (Olympus BXFM) with a spatial resolution better than 1 μm. The measurements were done with the laser beam focused on a single nanotube at a time. DFT calculations All

Glucose-derived carbon materials with tailored properties as electrocatalysts for the oxygen reduction reaction

• Rafael Gomes Morais,
• Natalia Rey-Raap,
• José Luís Figueiredo and
• Manuel Fernando Ribeiro Pereira

Beilstein J. Nanotechnol. 2019, 10, 1089–1102, doi:10.3762/bjnano.10.109

• potentials (0.75–0.78 V and 0.30–0.33 V), indicating that the ORR mechanism proceeds via the two-electron pathway. These results are corroborated by the experiments performed with a rotating ring disk electrode, from which the production of hydrogen peroxide was evaluated. More than 18% of hydrogen peroxide

• analysis, a calibration of the CO and CO2 content was carried out, allowing the quantification of the TPD profiles. Electrochemical characterization The electrochemical measurements were performed on a PGSTAT 302N potentiostat/galvanostat by using a three-electrode cell configuration. Ag/AgCl (KCl 3 M) and

• a glassy carbon rod were used as reference and counter electrode, respectively. Working electrodes were prepared by depositing a suspension of the carbon samples on a glassy carbon rotating disk electrode (3 mm of diameter, Metrohm). These suspensions were prepared by dispersing 1 mg of the prepared

Tailoring the stability/aggregation of one-dimensional TiO₂(B)/titanate nanowires using surfactants

• Atiđa Selmani,
• Johannes Lützenkirchen,
• Kristina Kučanda,
• Dario Dabić,
• Engelbert Redel,
• Ida Delač Marion,
• Damir Kralj,
• Darija Domazet Jurašin and
• Maja Dutour Sikirić

Beilstein J. Nanotechnol. 2019, 10, 1024–1037, doi:10.3762/bjnano.10.103

• Riedel-de Haën and used for pH-electrode calibration. All other chemicals used in this investigation were purchased from Fluka and dissolved in Milli-Q water. Sample preparation Preparation of neat surfactant solutions Stock solutions of DTAB, c(DTAB) = 1 × 10−1 mol dm−3 and 12-2-12, c(12-2-12) = 1 × 10

• after each addition of titrant in order to obtain stable pH electrode response. The pH was recorded using a pH meter (827 pH Lab, Metrohm) equipped with a combined glass electrode (6.0228.010, Metrohm) which was calibrated with five standard buffers (pH 2, 4, 6, 8 and 10). During the experiments

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

• recently, a technique for nanoscale and uniform surface etching of the carbon fiber surface was developed and a significant enhancement of the negative electrode reaction of vanadium redox flow batteries was attained, although the enhancement was limited to the positive electrode reaction. In this study

• photoelectron spectroscopy (XPS). The activity for the vanadium ion redox reactions was evaluated by cyclic voltammetry (CV) to demonstrate the enhancement of both the positive and negative electrode reactions. A full cell test of the vanadium redox flow battery (VRFB) showed a significant decrease of the

• overpotential and a stable cycling performance. A facile and efficient technique based on the nanoscale processing of the carbon fiber surface was presented to substantially enhance the activity for the redox reactions in redox flow batteries. Keywords: carbon fiber; electrode reactions; metal-oxide

Direct growth of few-layer graphene on AlN-based resonators for high-sensitivity gravimetric biosensors

• Jimena Olivares,
• Teona Mirea,
• Lorena Gordillo-Dagallier,
• Bruno Marco,
• José Miguel Escolano,
• Marta Clement and
• Enrique Iborra

Beilstein J. Nanotechnol. 2019, 10, 975–984, doi:10.3762/bjnano.10.98

• and patterned over the top electrode of the shear-mode SMRs. The active area of the resonators was subsequently functionalized using both covalent and non-covalent schemes that ended with the successful detection of antibodies without significant worsening of the resonator performance. Opposite to

• inductance associated to the extension of the top electrode. To accurately track the resonant frequency during detection, these parasites can be removed by software. However, in practical oscillators this inductance should be removed (or minimized) by a careful design of the resonator and the fluidic system

• the films involved in the SMR structure were deposited by sputtering, except the Ir bottom electrode and the Ni catalyst that were e-beam evaporated. The deposition conditions of the AlN and SiO2 layers in the reflector were carefully adjusted to minimize residual stresses in each film. The final

In situ AFM visualization of Li–O₂ battery discharge products during redox cycling in an atmospherically controlled sample cell

• Kumar Virwani,
• Younes Ansari,
• Khanh Nguyen,
• Francisco José Alía Moreno-Ortiz,
• Jangwoo Kim,
• Maxwell J. Giammona,
• Ho-Cheol Kim and
• Young-Hye La

Beilstein J. Nanotechnol. 2019, 10, 930–940, doi:10.3762/bjnano.10.94

• /bjnano.10.94 Abstract The in situ observation of electrochemical reactions is challenging due to a constantly changing electrode surface under highly sensitive conditions. This study reports the development of an in situ atomic force microscopy (AFM) technique for electrochemical systems, including the

• Nyquist plot inset of Figure 2. This mid-frequency circle is notably absent in the case of the cell with <20 ppm of water. To construct an equivalent circuit model, the resistance between the electrode and current collectors is represented by Rs. The passivated film on the electrode has an interfacial

• , the cell had a relatively small discharge capacity of 2.2 µAh. Despite reaching the prescribed voltage cut-off, it is clear from the AFM images that the capacity of this cell is not limited by electrode surface area (a failure mechanism known as electrode cloging) as free areas of the electrode

Synthesis of novel C-doped g-C₃N₄ nanosheets coupled with CdIn₂S₄ for enhanced photocatalytic hydrogen evolution

• Jingshuai Chen,
• Chang-Jie Mao,
• Helin Niu and
• Ji-Ming Song

Beilstein J. Nanotechnol. 2019, 10, 912–921, doi:10.3762/bjnano.10.92

• photospectroscopy (Hitachi F-4500). Photocurrent measurements The photocurrent response of the photocatalyts were measured using a standard three-electrode electrochemical station (CHI 660D, Chenhua Instrument Co., Ltd, Shanghai, China). In this system, the Ag/AgCl electrode was chosen as the reference electrode

• and a Pt wire was used as the counter electrode, respectively. The electrolyte was a 1 M Na2SO4 aqueous solution. A glassy carbon electrode containing the as-prepared sample served as the working electrode. Photocatalytic H2 production reaction In this work, the activity of the photocatalyst was

Novel reversibly switchable wettability of superhydrophobic–superhydrophilic surfaces induced by charge injection and heating

• Xiangdong Ye,
• Junwen Hou and
• Dongbao Cai

Beilstein J. Nanotechnol. 2019, 10, 840–847, doi:10.3762/bjnano.10.84

• environments. At 150 V, the maximum contact angle could be reduced by 23° by electrical wetting in a reversible manner. Li et al. [23] studied the diffusion of droplets of ionic liquids on an insulating electrode subjected to an external voltage. The catalytic effect of a vertical electric field on the

• remained unchanged at 150.5°. As the voltage increased to 1600 V, the contact angle decreased sharply to 20°. When the voltage increased to 2000 V, the contact angle decreased to 8.1° and the coating became superhydrophilic, as shown in Figure 5. The electrode contact area of the coating became

• superhydrophilic but the uncontacted area remained superhydrophobic, as shown in Figure 6. We examined the morphology of the electrode contact area in the coating by SEM and AFM, as shown in Figure 7. There was no obvious morphology change in electrode contact area compared with the electrode non-contact area

An efficient electrode material for high performance solid-state hybrid supercapacitors based on a Cu/CuO/porous carbon nanofiber/TiO₂ hybrid composite

• Mamta Sham Lal,
• Thirugnanam Lavanya and
• Sundara Ramaprabhu

Beilstein J. Nanotechnol. 2019, 10, 781–793, doi:10.3762/bjnano.10.78

• electrode in a three-electrode configuration. The solid-state hybrid supercapacitor (SSHSC) fabricated based on this composite exhibits a high specific capacitance value of 330 F g−1 at a current density of 1 A g−1 with 78.8% capacitance retention for up to 10,000 cycles. At the same time, a high energy

• density of 45.83 Wh kg−1 at a power density of 1.27 kW kg−1 was also realized. The developed electrode material provides new insight into ways to enhance the electrochemical properties of solid-state supercapacitors, based on the synergistic effect of porous carbon nanofibers, metal and metal oxide

• , and stand-by power systems [4][5]. Supercapacitors may be categorized by their energy storage mechanism into (i) electrochemical double-layer capacitors (EDLCs) and (ii) pseudo-supercapacitors. EDLCs, electrostatically store energy in a non-faradaic manner at the electrode–electrolyte interface, where

Trapping polysulfide on two-dimensional molybdenum disulfide for Li–S batteries through phase selection with optimized binding

• Sha Dong,
• Xiaoli Sun and
• Zhiguo Wang

Beilstein J. Nanotechnol. 2019, 10, 774–780, doi:10.3762/bjnano.10.77

• surface-to-volume ratio. An ideal anchoring material should display a binding energy with LPSs in the range from 0.8 to 2.0 eV in order to effectively trap Li2Sx [8], and good electrical and ionic conductivity. Nanostructured MoS2 used as an electrode material for lithium-ion batteries shows a higher

On the transformation of “zincone”-like into porous ZnO thin films from sub-saturated plasma enhanced atomic layer deposition

• Alberto Perrotta,
• Julian Pilz,
• Stefan Pachmajer,
• Antonella Milella and
• Anna Maria Coclite

Beilstein J. Nanotechnol. 2019, 10, 746–759, doi:10.3762/bjnano.10.74

• in an asymmetrical plate configuration, in which the showerhead radio frequency (RF, at 13.56 MHz) electrode and ground electrode had a distance of 8 cm. Diethylzinc (DEZ, Sigma-Aldrich, CAS 557-20-0) was used as the metalorganic precursor. Pure oxygen (air liquide, 99.9995%) was used during the

An iridescent film of porous anodic aluminum oxide with alternatingly electrodeposited Cu and SiO₂ nanoparticles

• Menglei Chang,
• Huawen Hu,
• Haiyan Quan,
• Hongyang Wei,
• Zhangyi Xiong,
• Jiacong Lu,
• Pin Luo,
• Yaoheng Liang,
• Jianzhen Ou and
• Dongchu Chen

Beilstein J. Nanotechnol. 2019, 10, 735–745, doi:10.3762/bjnano.10.73

• simultaneous way, into a stable structure possessing a regular geometric appearance. In contrast, electrodeposition involves the nucleation at an electrode surface under the action of an electric field [25]. For example, a high-purity aluminum foil was directly used as a template, on which anodic aluminum

• s deposition. The sample was kept parallel to the electrode, and the distance between the sample and electrodes was kept equal during the deposition process. After the deposition, the sample was removed, washed with DI water to get rid of the SiO2 deposition liquid, blow-dried with a hair dryer, and

• approximately 5.7 cm2. After being allowed to stand for 24 h, the sample was exposed to the electrochemical impedance measurements. A three-electrode system was adopted for the measurements, and a Pt wire and a saturated calomel electrode (SCE) were employed as the auxiliary electrode and reference electrode

A carrier velocity model for electrical detection of gas molecules

• Ali Hosseingholi Pourasl,
• Sharifah Hafizah Syed Ariffin,
• Mohammad Taghi Ahmadi,
• Razali Ismail and
• Niayesh Gharaei

Beilstein J. Nanotechnol. 2019, 10, 644–653, doi:10.3762/bjnano.10.64

• ) unit cell. Carrier velocity versus carrier concentration in armchair graphene nanoribbon (AGNR). Illustration of the gas sensor with the 8-AGNR FET platform. The structure consists of the left and right electrode and the channel region in the middle with a metal back gate. Orientation of CO and NO gas

Review of time-resolved non-contact electrostatic force microscopy techniques with applications to ionic transport measurements

• Aaron Mascaro,
• Yoichi Miyahara,
• Tyler Enright,
• Omur E. Dagdeviren and
• Peter Grütter

Beilstein J. Nanotechnol. 2019, 10, 617–633, doi:10.3762/bjnano.10.62

• conducting materials as well. To probe ionic transport a step potential is applied between the AFM tip and a conducting back electrode, creating an electric field across the tip–sample gap and through the sample, illustrated in Figure 1b. The mobile ions inside the sample move in response to this field over

• between the tip and back electrode, creating an electric field that extends through the sample. (c) The mobile ions move towards the tip (in the case of a negative tip bias and grounded back electrode), shielding the internal electric field. (a) AFM frequency shift response to stretched-exponential

Hydrophilicity and carbon chain length effects on the gas sensing properties of chemoresistive, self-assembled monolayer carbon nanotube sensors

• Juan Casanova-Cháfer,
• Carla Bittencourt and
• Eduard Llobet

Beilstein J. Nanotechnol. 2019, 10, 565–577, doi:10.3762/bjnano.10.58

• the recovery time include heating or UV irradiating the gas-sensitive film during the recovery phase to ease desorption of molecules from the surface, increasing the flow rate during both detection and recovery phases or further optimizing the sensor parameters such as electrode design or CNT density

• were taken at 80 kV. Fabrication of the sensor substrate A 10 × 10 mm2 alumina substrate was employed. Interdigitated electrodes and a heating resistor were screen-printed on either side of the substrate employing a platinum ink (see Supporting Information File 1, Figure S6). The electrode area was

Mo-doped boron nitride monolayer as a promising single-atom electrocatalyst for CO₂ conversion

• Qianyi Cui,
• Gangqiang Qin,
• Weihua Wang,
• Lixiang Sun,
• Aijun Du and
• Qiao Sun

Beilstein J. Nanotechnol. 2019, 10, 540–548, doi:10.3762/bjnano.10.55

• hydrogenation step, *H2O production with an energy input 0.45 eV for CO2 reduction to CH4. According to the computational hydrogen electrode (CHE) model, the limiting potential (Ulim) is defined as: Ulim = −∆Gmax/e, where ∆Gmax is the largest free energy in CRR. Therefore, the limiting potential of CRR on the

• database [64], and the data of ZPE and entropy for the gas molecules at 298.15 K are shown in Table S1 in the Supporting Information File 1. ΔGU is the free energy of the electrode potential, which is ΔGU = −neU (n is the number of electrons transferred corresponding to the elementary steps and U is the

• electrode potential). ΔGpH is the free energy contribution of the H+ concentration. The expression is ΔGpH = 2.303 × kBT × pH, where kB is the Boltzmann constant (kB = 1.38 × 10−23 J/K), and the pH was set at zero in the study to simulate acidic conditions. (a) Adsorption energy of CO2 and H2O on various

A porous 3D-RGO@MWCNT hybrid material as Li–S battery cathode

• Yongguang Zhang,
• Jun Ren,
• Yan Zhao,
• Taizhe Tan,
• Fuxing Yin and
• Yichao Wang

Beilstein J. Nanotechnol. 2019, 10, 514–521, doi:10.3762/bjnano.10.52

• region the x-intercept is attributed to the contact resistance (R0), and the semicircle is attributed to the charge-transfer resistance (Rct) at the electrode/electrolyte interface. Finally, the inclined slope in the low-frequency region is associated with the Warburg impedance (W) [28], which correlates

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

• , Poland 10.3762/bjnano.10.49 Abstract Composites based on the titania nanotubes were tested in aqueous electrolyte as a potential electrode material for energy storage devices. The nanotubular morphology of TiO2 was obtained by Ti anodization. TiO2 nanotubes were covered by a thin layer of bismuth

• counter ions. Each stage of modification and deposition affected the overall capacitance and allowed for an expansion of the potential range of electroactivity. Multiple charge/discharge cycles were performed to characterize the electrochemical stability of the inorganic–organic hybrid electrode

• candidates for storage because of fast charging/discharging processes, relatively simple structures, easy large-scale production and high power densities [5]. It is crucial to look for electrochemically stable electrode materials that exhibit high specific capacitance and can be rapidly and reversibly

Wearable, stable, highly sensitive hydrogel–graphene strain sensors

• Jian Lv,
• Chuncai Kong,
• Chao Yang,
• Lu Yin,
• Itthipon Jeerapan,
• Fangzhao Pu,
• Xiaojing Zhang,
• Sen Yang and
• Zhimao Yang

Beilstein J. Nanotechnol. 2019, 10, 475–480, doi:10.3762/bjnano.10.47

• flakes. The schematic structure and a photograph of the composite electrode is shown in Figure 1b and Figure 1c, respectively. Besides serving to retain water in the hydrogel, the presence of glycerol also improves the mechanical performance of the hydrogel, as shown in Figure 2a and 2b. Figure 2a shows

• stress to 0.06 MPa at a strain of 2000%. The difference between the two hydrogels in the compressing strain–stress curve is not much as that in tensile mode, as shown in Figure 2b. An image of the synthesized graphene–hydrogel electrode is shown in Figure 2c. A uniform film is formed on the surface of