Humidity-dependent electrical performance of CuO nanowire networks studied by electrochemical impedance spectroscopy

• Jelena Kosmaca,
• Juris Katkevics,
• Jana Andzane,
• Raitis Sondors,
• Liga Jasulaneca,
• Raimonds Meija,
• Kiryl Niherysh,
• Yelyzaveta Rublova and
• Donats Erts

Beilstein J. Nanotechnol. 2023, 14, 683–691, doi:10.3762/bjnano.14.54

• , Riga, Latvia 10.3762/bjnano.14.54 Abstract Electrochemical impedance spectroscopy was applied for studying copper oxide (CuO) nanowire networks assembled between metallic microelectrodes by dielectrophoresis. The influence of relative humidity (RH) on electrical characteristics of the CuO nanowire

• nanowires are synthesized by thermal oxidation [9] and aligned between metallic microelectrodes by DEP [26]. Electrical properties of the nanowire-based system at various RH values are assessed by EIS [27][28]. To attempt a systematic study on the suitability of the CuO nanowire networks for different

• of nanostructured CuO, and indicate directions for further applications in humidity sensors and other systems with nanowire interconnects. Results and Discussion The synthesized CuO nanowires (Figure 1a) were assembled between arrays of lithographically defined Au microelectrodes on a Si/SiO2 chip

Tubular glassy carbon microneedles with fullerene-like tips for biomedical applications

• Sharali Malik and
• George E. Kostakis

Beilstein J. Nanotechnol. 2022, 13, 455–461, doi:10.3762/bjnano.13.38

• thermally conducting, and mechanically strong [1]. Therefore, biomedical applications for glassy carbon microneedles include the use as alternatives to stainless steel surgical needles in acupuncture and as microelectrodes in neural prosthetics [9][14]. Experimental Sample preparation The samples were

Recent progress in actuation technologies of micro/nanorobots

• Ke Xu and
• Bing Liu

Beilstein J. Nanotechnol. 2021, 12, 756–765, doi:10.3762/bjnano.12.59

• microelectrodes in water and solutions of high ionic strength. When the ultrasonic frequency is tuned to generate a vertical standing wave, the metal rod is suspended in the midpoint plane of a cylindrical cell. A rapid axial movement of 200 μm/s of the metal microprobe at the resonance frequency was observed

Sensing behavior of flower-shaped MoS₂ nanoflakes: case study with methanol and xylene

• Maryam Barzegar,
• Masoud Berahman and
• Azam Iraji zad

Beilstein J. Nanotechnol. 2018, 9, 608–615, doi:10.3762/bjnano.9.57

• , dispersed flower-shaped MoS2 nanoflakes in ethanol were first deposited on a 1 × 1 cm2 alumina wafer by spin coating. Then the gold microelectrodes were deposited on selective areas of the prepared, uniform, thin film through a comb-shaped shadow mask by sputtering. The mask was then lifted off and the

• microelectrodes with 100 µm width and a 200 µm gap between each electrode remained and were annealed at 200 °C for 120 min for better film adhesion. Gas sensing measurements In order to test the samples toward different gas molecules, a dynamic system based on N2 as a carrier gas is used. For testing the sensor

Study of the vertically aligned in-plane switching liquid crystal mode in microscale periodic electric fields

• Artur R. Geivandov,
• Mikhail I. Barnik,
• Irina V. Kasyanova and
• Serguei P. Palto

Beilstein J. Nanotechnol. 2018, 9, 11–19, doi:10.3762/bjnano.9.2

• electrodes width-to-gap ratio we have found the LC cell parameters enabling both high transmittance and fast response times. The VA-IPS mode with transparent microelectrodes is a perspective for display application requiring small pixel size and fast response time. Experimental Samples preparation: We used

Parylene C as a versatile dielectric material for organic field-effect transistors

• Tomasz Marszalek,
• Maciej Gazicki-Lipman and
• Jacek Ulanski

Beilstein J. Nanotechnol. 2017, 8, 1532–1545, doi:10.3762/bjnano.8.155

• of organic electronics. One of the early applications of Parylene C encapsulation layer in an electronic structure was that of a microelectrode insulator [65]. The Parylene C-covered iridium and tungsten microelectrodes were investigated by means of in vivo and in vitro impedance tests. In vitro

• unchanged impedance of the microelectrodes protected by Parylene C layers has been recorded for over four months [66]. As another positive result, no destructive influence of the encapsulation material was observed when Parylene C had been employed to protect a pentacene OFET device, where no remarkable

Copper atomic-scale transistors

• Fangqing Xie,
• Maryna N. Kavalenka,
• Moritz Röger,
• Daniel Albrecht,
• Hendrik Hölscher,
• Jürgen Leuthold and
• Thomas Schimmel

Beilstein J. Nanotechnol. 2017, 8, 530–538, doi:10.3762/bjnano.8.57

• -scale transistors and confirmed that copper atomic-scale transistors can be fabricated and operated electrochemically in a copper electrolyte (CuSO4 + H2SO4) in bi-distilled water under ambient conditions with three microelectrodes (source, drain and gate). The electrochemical switching-on potential of

• microscope objective was contacted with a drop of copper electrolyte (CuSO4 (4 mM) + H2SO4 (0.1 M)), and a copper wire serving as a counter electrode was partially immersed in the electrolyte. Electrochemical deposition/dissolution processes on the microelectrodes were observed in situ with a confocal

• logic and memory operations. This merging of logic with memory opens perspectives for processor-in-memory and logic-in-memory architectures based on metallic atomic-scale transistors. Experimental Fabrication of microelectrodes Method 1: Two masks with patterns for microelectrodes and windows in the

Functional fusion of living systems with synthetic electrode interfaces

• Oskar Staufer,
• Sebastian Weber,
• C. Peter Bengtson,
• Hilmar Bading,
• Joachim P. Spatz and
• Amin Rustom

Beilstein J. Nanotechnol. 2016, 7, 296–301, doi:10.3762/bjnano.7.27

• diagnostics utilizing biomolecular machineries “perfected” during billion years of evolution. To date, hardware–wetware interfaces that sample or modulate bioelectric potentials, such as neuroprostheses or implantable energy harvesters, are mostly based on microelectrodes brought into the closest possible

• cytoplasm or, at later time points, nutrient shortage. This view is corroborated by our own (Supporting Information File 1, Figure S1a) as well as other various electrophysiology studies, observing rapid ejection of intracellular glass microelectrodes from Physarum p. [10]. This is presumably due to its

Correction: Carbon-based smart nanomaterials in biomedicine and neuroengineering

• Antonina M. Monaco and
• Michele Giugliano

Beilstein J. Nanotechnol. 2015, 6, 499–499, doi:10.3762/bjnano.6.51

• Computer Science, University of Sheffield, S1 4DP Sheffield, UK 10.3762/bjnano.6.51 Keywords: carbon nanotubes; electrophysiology; graphene; microelectrodes; nanodiamonds; nanotechnology; neuroengineering; neuronal cultures; neuroscience; Correction for the Acknowledgement section, the correct text

Carbon-based smart nanomaterials in biomedicine and neuroengineering

• Antonina M. Monaco and
• Michele Giugliano

Beilstein J. Nanotechnol. 2014, 5, 1849–1863, doi:10.3762/bjnano.5.196

• ; electrophysiology; graphene; microelectrodes; nanodiamonds; nanotechnology; neuroengineering; neuronal cultures; neuroscience; Introduction Over the past few years, the gap between materials sciences and biology has increasingly narrowed. This has enabled substantial progress within interdisciplinary approaches

• adhesion. Since then, several studies [106] have revealed that CNTs are able to guide neuronal adhesion and to impact neuronal networks. Microelectrode arrays (MEAs – extracellular recording and stimulation of neuronal activity): MEAs are devices consisting of metallic microelectrodes (i.e., made of Au, Pt

• , or titanium nitrate) and embedded in a planar substrate, arranged in an array and connected to an external electrical circuitry. By using individual microelectrodes it is possible to stimulate or record neural electrical activity non-invasively, both in vivo and in vitro. For these applications

Constant-distance mode SECM as a tool to visualize local electrocatalytic activity of oxygen reduction catalysts

• Michaela Nebel,
• Thomas Erichsen and
• Wolfgang Schuhmann

Beilstein J. Nanotechnol. 2014, 5, 141–151, doi:10.3762/bjnano.5.14

• microscopy (4D SF/CD-SECM) was utilized for the investigation of the activity distribution of oxygen reduction catalysts. Carbon-supported Pt model catalyst powders have been immobilized in recessed microelectrodes and compared to a spot preparation technique. Microcavities serve as platform for the binder

• high-resolution SECM experiments to powder-based catalyst preparations. Keywords: electrocatalysis; oxygen reduction; recessed microelectrodes; redox-competition SECM; SECM; scanning electrochemical microscopy; shearforce-based constant-distance mode; Introduction In scanning electrochemical

• ). Furthermore, recessed microelectrodes fabricated by etching inlayed Au disk microelectrodes are demonstrated as a flexible platform for immobilization of catalyst powders for cd-mode SECM experiments. The microcavities (also referred to as micropores) have already demonstrated their applicability for integral

Ultramicrosensors based on transition metal hexacyanoferrates for scanning electrochemical microscopy

• Maria A. Komkova,
• Angelika Holzinger,
• Andreas Hartmann,
• Alexei R. Khokhlov,
• Christine Kranz,
• Arkady A. Karyakin and
• Oleg G. Voronin

Beilstein J. Nanotechnol. 2013, 4, 649–654, doi:10.3762/bjnano.4.72

• electrochemical deposition of six layers of hexacyanoferrates (HCF), more specifically, an alternating pattern of three layers of Prussian Blue and three layers of Ni–HCF. The microelectrodes modified with mixed layers were continuously monitored in 1 mM hydrogen peroxide and proved to be stable for more than 5 h

• under these conditions. The mixed layer microelectrodes exhibited a stability which is five times as high as the stability of conventional Prussian Blue-modified UMEs. The sensitivity of the mixed layer sensor was 0.32 A·M−1·cm−2, and the detection limit was 10 µM. The mixed layer-based UMEs were used

• microelectrodes were also applied in SECM experiments to map hydrogen peroxide profiles in substrate-generation-tip-collection mode (see Figure 4). As clearly visible in the SECM image, the reduction current significantly increased when the PB–Ni-modified electrode was scanned towards the center of the H2O2

Self-assembled monolayers and titanium dioxide: From surface patterning to potential applications

• Yaron Paz

Beilstein J. Nanotechnol. 2011, 2, 845–861, doi:10.3762/bjnano.2.94

• having specificity, which utilized the “adsorb & shuttle” concept. In a different study, octyltrichlorosilane (OCTS) SAMs chemisorbed on TiO2 microelectrodes in an interdigitated TiO2/Pt array were used to study the performance of an electrophotocatalytic cell as a function of applied bias [52]. The