Design aspects of Bi₂Sr₂CaCu₂O_8+δ THz sources: optimization of thermal and radiative properties

• Mikhail M. Krasnov,
• Natalia D. Novikova,
• Roger Cattaneo,
• Alexey A. Kalenyuk and
• Vladimir M. Krasnov

Beilstein J. Nanotechnol. 2021, 12, 1392–1403, doi:10.3762/bjnano.12.103

• Center, SE-10691 Stockholm, Sweden Institute of Metal Physics of National Academy of Sciences of Ukraine, 03142 Kyiv, Ukraine Kyiv Academic University, 03142 Kyiv, Ukraine 10.3762/bjnano.12.103 Abstract Impedance matching and heat management are important factors influencing the performance of terahertz

• crystal and the electrode leads to appearance of a large parasitic capacitance, which shunts terahertz emission and prevents impedance matching with open space. The overlap is avoided in whisker-based devices. Furthermore, the whisker and the electrodes form a turnstile (crossed-dipole) antenna

• facilitating good impedance matching. This leads to more than an order of magnitude enhancement of the radiation power efficiency in whisker-based, compared to crystal-based, devices. These results are in good agreement with presented experimental data. Keywords: high-temperature superconductivity; Josephson

Electrical, electrochemical and structural studies of a chlorine-derived ionic liquid-based polymer gel electrolyte

• Ashish Gupta,
• Amrita Jain,
• Manju Kumari and
• Santosh K. Tripathi

Beilstein J. Nanotechnol. 2021, 12, 1252–1261, doi:10.3762/bjnano.12.92

• polymer system. Along with the ionic liquid, magnesium salt was also used to prepare the final polymer films. The prepared films possess good dimensional and mechanical stability with acceptable parameters. Impedance spectroscopic studies confirmed that there is an increase in the room-temperature ionic

• conductivity of the prepared electrolyte films when the ionic liquid content is increased. The highest room-temperature ionic conductivity was found to be in the order of ≈8.9 × 10−3 S·cm−1 for the optimized system. The XRD data were also in line with the impedance data, confirming the increase in the

• time of fabrication of the devices. In the present study, σ was recorded by using complex impedance spectroscopic techniques, carried out by an LCR Hi-Tester (HIOKI-3522-50, Japan) in the frequency range of 100 kHz to 1 Hz with a signal level of 10 mV. The ionic conductivity was calculated by using

An overview of microneedle applications, materials, and fabrication methods

• Zahra Faraji Rad,
• Philip D. Prewett and
• Graham J. Davies

Beilstein J. Nanotechnol. 2021, 12, 1034–1046, doi:10.3762/bjnano.12.77

• skin diseases including cancer, via electrical impedance measurements [52]. Microneedle structure design Several factors should be considered when designing microneedles for skin penetration: (1) geometric features, such as length, diameter, tip size, and shape, (2) physical form: solid, hollow, side

Comprehensive review on ultrasound-responsive theranostic nanomaterials: mechanisms, structures and medical applications

• Sepand Tehrani Fateh,
• Lida Moradi,
• Elmira Kohan,
• Michael R. Hamblin and
• Amin Shiralizadeh Dezfuli

Beilstein J. Nanotechnol. 2021, 12, 808–862, doi:10.3762/bjnano.12.64

• conditions [32][33][34][35]. Acoustic impedance, attenuation, acoustic power, intensity, frequency, beam shape, and exposure time are important parameters for the utilization of US devices. Moreover, the anatomical location of the US application and the characteristics of the transduction medium should be

• values of acoustic impedance (a parameter that mainly depends on the tissue density), a proportion of the wave energy is reflected while the remainder passes through the tissue in a process called transmission. Other consequences are the refraction and diffraction of the acoustic wave. Also, a proportion

Boosting of photocatalytic hydrogen evolution via chlorine doping of polymeric carbon nitride

• Malgorzata Aleksandrzak,
• Michalina Kijaczko,
• Wojciech Kukulka,
• Daria Baranowska,
• Martyna Baca,
• Beata Zielinska and
• Ewa Mijowska

Beilstein J. Nanotechnol. 2021, 12, 473–484, doi:10.3762/bjnano.12.38

• three cycles of light on–off, the performance of both electrodes tends to stabilize, indicating that the photocatalysts are stable under visible-light irradiation [55]. The measurements obtained from electrochemical impedance spectroscopy (EIS) are shown in Figure 9b. It is known that the arc radius of

• the EIS spectrum is related to the charge-transfer resistance at the electrode–electrolyte interface [71]. The EIS arc radius of Cl-PCN is smaller than that of PCN. Its impedance is reduced compared to PCN, indicating that Cl doping decreased the charge-transfer resistance of polymeric carbon nitride

• (F7000, Hitachi) with an excitation wavelength of 280 nm. The DRS was performed using a Jasco (Japan) spectrometer. The Kubelka–Munk function was used to calculate the bandgap energy. The photocurrent response and electrochemical impedance spectroscopy were measured using the Autolab PGSTAT302 N

Solution combustion synthesis of a nanometer-scale Co₃O₄ anode material for Li-ion batteries

• Monika Michalska,
• Huajun Xu,
• Qingmin Shan,
• Shiqiang Zhang,
• Yohan Dall'Agnese,
• Yu Gao,
• Amrita Jain and
• Marcin Krajewski

Beilstein J. Nanotechnol. 2021, 12, 424–431, doi:10.3762/bjnano.12.34

• Co3O4 electrode. In order to better understand of the capacitive behavior of the investigated Co3O4 electrode material, electrochemical impedance spectroscopy (EIS) measurements at a current density of 100 mA·g−1 were carried out before cycling and after the first, second, third, fourth, and fifth cycle

• Information File 1. These EIS features represent the charge transfer at the electrode–electrolyte interface (Rct) and the Warburg impedance (W), which is attributed to the diffusion of Li+ ions in the bulk electrode material [25][38]. The plots for the cycled cell are slightly different. They are composed of

• represent the charge transfer at the electrode–electrolyte interface (Rct) and the Warburg impedance (W), respectively. The semicircle at high frequencies is mainly attributed to SEI resistance (RSEI) and contact resistance (Rf) [13][15][20][21][25][38]. At this point, it should be also mentioned that the

A stretchable triboelectric nanogenerator made of silver-coated glass microspheres for human motion energy harvesting and self-powered sensing applications

• Hui Li,
• Yaju Zhang,
• Yonghui Wu,
• Hui Zhao,
• Weichao Wang,
• Xu He and
• Haiwu Zheng

Beilstein J. Nanotechnol. 2021, 12, 402–412, doi:10.3762/bjnano.12.32

• decline after 3000 cycles for 25 min, demonstrating the long-term stable operation of the S-TENG on the human body. The impedance matching experiment was designed to measure the powering capability of the S-TENG with different resistances. Figure 4c,d shows the relationship between load resistance and ISC

Intracranial recording in patients with aphasia using nanomaterial-based flexible electronics: promises and challenges

• Qingchun Wang and
• Wai Ting Siok

Beilstein J. Nanotechnol. 2021, 12, 330–342, doi:10.3762/bjnano.12.27

• covering almost the whole brain. The application of novel nanomaterials has the potential to overcome the limitations of conventional electrode arrays. IEEG electrode arrays electroplated with nanoparticles could lower impedance and allow for a closer contact with cortical cells, thereby providing more

• µm PI layers. The bifurcated flap shape was used to achieve good penetration and attachment to the cortical surface and avoid injuring blood vessels on the brain midline (Figure 5c, left). The width of the Au lines was designed to be 100 µm to reach a low impedance value and enhance the signal-to

Toward graphene textiles in wearable eye tracking systems for human–machine interaction

• Ata Jedari Golparvar and
• Murat Kaya Yapici

Beilstein J. Nanotechnol. 2021, 12, 180–189, doi:10.3762/bjnano.12.14

• this way, “passive” graphene textile electrodes were formed, which can be directly used to capture surface biopotentials without further modification. Conductivity measurements showed resistance values of the textiles between 1 and 10 kΩ and skin-electrode impedance values from 87.5 kΩ (at 10 Hz) to

• ” electrodes, the functionality of which degrades over time [23]. However, one common issue in dry electrodes is the relatively high skin-electrode contact impedance, which causes susceptibility to physical movements and power line interferences resulting in signal distortions. While the flexible, foldable

• nature of textile electrodes promotes wearability, it can adversely lead to dynamic contact conditions and, thereby, motion artifacts in the acquired signal. A strategy to minimize this effect, which was investigated in this work, is to reduce the impedance of the signal source by utilizing a buffer

Paper-based triboelectric nanogenerators and their applications: a review

• Jing Han,
• Nuo Xu,
• Yuchen Liang,
• Mei Ding,
• Junyi Zhai,
• Qijun Sun and
• Zhong Lin Wang

Beilstein J. Nanotechnol. 2021, 12, 151–171, doi:10.3762/bjnano.12.12

• groups on its surface. The basis of a GO humidity sensor is the variation of impedance or capacitance owing to the tendency of the water molecules to be adsorbed on the GO surface. The rich functional groups of GO and the flexibility of GO paper deliver the significant potential for a less complicated

ZnO and MXenes as electrode materials for supercapacitor devices

• Ameen Uddin Ammar,
• Ipek Deniz Yildirim,
• Feray Bakan and
• Emre Erdem

Beilstein J. Nanotechnol. 2021, 12, 49–57, doi:10.3762/bjnano.12.4

• ) spectroscopy techniques among the most powerful techniques to extract detailed information on the defect structures of ZnO. Also, electrical impedance spectroscopy (EIS) and cyclic voltammetry (CV) are sensitive to electrical properties such as specific capacitance and impedance, which can be correlated with

• and enable the device to act as a battery. Thus one may call such devices “superbat” (battery-like supercapacitors) [11]. To measure the impedance of the electrodes and, hence, the device, an AC voltage is applied and the real and the imaginary part of the impedance are plotted. Such a plot is called

Self-standing heterostructured NiC_x-NiFe-NC/biochar as a highly efficient cathode for lithium–oxygen batteries

• Shengyu Jing,
• Xu Gong,
• Shan Ji,
• Linhui Jia,
• Bruno G. Pollet,
• Sheng Yan and
• Huagen Liang

Beilstein J. Nanotechnol. 2020, 11, 1809–1821, doi:10.3762/bjnano.11.163

• impedance spectroscopy (EIS) in a frequency range from 100 kHz to 0.1 Hz and with a perturbation amplitude of 5 mV was used on the PARSTAT 4000 (AMETEK, USA) electrochemical workstation. Cyclic voltammetry (CV) was performed at a scan rate of 0.1 mV·s−1 and in a cell voltage range from 2.0 to 4.5 V vs Li

• existence of some amount of undecomposed Li2O2. Electrochemical impedance spectroscopy was also carried out to investigate NiFe-PBA/PP-T samples after the first charge and discharge (Figure 8c and Figure 8d). The illustrations (top part of Figure 8c and Figure 8d) show the corresponding equivalent circuit

• full charge at 0.1 mA·cm−2. Electrochemical impedance spectra of (c) NiFe-PBA/PP-900 and of (d) NiFe-PBA/PP-700. Performance comparison of Li–O2 batteries. Fitted impedance parameters of Li–O2 batteries with NiFe-PBA/PP-900 and NiFe-PBA/PP-700 at different stages. Funding This work was supported by

Mapping of integrated PIN diodes with a 3D architecture by scanning microwave impedance microscopy and dynamic spectroscopy

• Rosine Coq Germanicus,
• Peter De Wolf,
• Florent Lallemand,
• Catherine Bunel,
• Serge Bardy,
• Hugues Murray and
• Ulrike Lüders

Beilstein J. Nanotechnol. 2020, 11, 1764–1775, doi:10.3762/bjnano.11.159

• ) (doped semiconducting layers) and “back end of line” (BEOL) layers (metallization, trench dielectric, and isolation) of highly integrated microelectronic devices. Based on atomic force microscopy, an electromagnetically shielded and electrically conductive tip is used in scanning microwave impedance

• microscopy (sMIM). sMIM allows for the characterization of the local electrical properties through the analysis of the microwave impedance of the metal–insulator–semiconductor nanocapacitor (nano-MIS capacitor) that is formed by tip and sample. A highly integrated monolithic silicon PIN diode with a 3D

• ; integrated PIN diode; nanoprobing; scanning probe microscopy (SPM); scanning microwave impedance microscopy (sMIM); spectroscopy; Introduction In “front end of line” (FEOL) processing, the control, detection, and quantification of the effective 2D distributions of active dopants in semiconductors are

Piezoelectric sensor based on graphene-doped PVDF nanofibers for sign language translation

• Shuai Yang,
• Xiaojing Cui,
• Rui Guo,
• Zhiyi Zhang,
• Shengbo Sang and
• Hulin Zhang

Beilstein J. Nanotechnol. 2020, 11, 1655–1662, doi:10.3762/bjnano.11.148

• glove with double-sided tape. The thin copper wires were connected to the input terminals of the analogue measurement channels of a National Instruments BNC-2111 connector block. Voltage and current were measured with a Keithley 6514 electrometer (200 TΩ input impedance). The analogue signal of each

Walking energy harvesting and self-powered tracking system based on triboelectric nanogenerators

• Mingliang Yao,
• Guangzhong Xie,
• Qichen Gong and
• Yuanjie Su

Beilstein J. Nanotechnol. 2020, 11, 1590–1595, doi:10.3762/bjnano.11.141

• -circuit current was 10.8 µA. The impedance dependence of the fabricated u-TENG is shown in Figure 3e. The maximum output power of 0.279 mW can be observed at a loading resistance of 300 MΩ in Figure 3f. A long-term stability test did not exhibit a noticeable response decline after 10000 cycles (inset of

Structure and electrochemical performance of electrospun-ordered porous carbon/graphene composite nanofibers

• Yi Wang,
• Yanhua Song,
• Chengwei Ye and
• Lan Xu

Beilstein J. Nanotechnol. 2020, 11, 1280–1290, doi:10.3762/bjnano.11.112

• station (CHI660E, Chenhua, Shanghai) by using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and constant current galvanostatic charge/discharge (GCD) techniques. A voltage range of 0–1.0 V was applied to the CV electrode at a scan rate of 25 mV·s−1. The impedance measurements of

• of these electrodes exhibited similar symmetrical isosceles triangles, which were consistent with the characteristics of the double-layer capacitor electrode and with the results of the CV curves. Electrochemical impedance spectroscopy (EIS) is a reliable method used to characterize electrode

• represents the rapid ion diffusion in the electrolyte and the adsorption on the surface of the electrode, indicating the ideal capacitance behavior of the electrode. In addition, the more vertical the curve is in the low-frequency region, the more ideal the supercapacitor [42][43]. Comparing the impedance

High permittivity, breakdown strength, and energy storage density of polythiophene-encapsulated BaTiO₃ nanoparticles

• Adnanullah Khan,
• Amir Habib and
• Adeel Afzal

Beilstein J. Nanotechnol. 2020, 11, 1190–1197, doi:10.3762/bjnano.11.103

• microscopy (JEOL JSM 6490LA SEM) and atomic force microscopy (JSPM-5200 scanning probe microscope). Electrical properties of the bulk materials are measured under ambient conditions with a Wayne Kerr 6505B precision impedance analyzer and a Hipotronics HD103 3kV DC Hipot Tester. Results and Discussion

Excitonic and electronic transitions in Me–Sb₂Se₃ structures

• Nicolae N. Syrbu,
• Victor V. Zalamai,
• Ivan G. Stamov and
• Stepan I. Beril

Beilstein J. Nanotechnol. 2020, 11, 1045–1053, doi:10.3762/bjnano.11.89

• (In–Sb2Se3) contacts, the structures were obtained by either thermal sputtering under vacuum or electrochemical deposition onto the cleaved faces of single crystals (Figure 3A). Current–voltage characteristics suggest that the contacts have an ohmic behavior. The impedance has a frequency dependence

Nickel nanoparticles supported on a covalent triazine framework as electrocatalyst for oxygen evolution reaction and oxygen reduction reactions

• Secil Öztürk,
• Yu-Xuan Xiao,
• Dennis Dietrich,
• Beatriz Giesen,
• Juri Barthel,
• Jie Ying,
• Xiao-Yu Yang and
• Christoph Janiak

Beilstein J. Nanotechnol. 2020, 11, 770–781, doi:10.3762/bjnano.11.62

• good electrochemical ORR performance of Ni/CTF-1-600-22 was investigated by electrochemical impedance spectroscopy (EIS). As shown in Figure 7, all CTF-1-600 materials exhibited a higher conductivity than CTF-1-400. This could be ascribed to the higher graphitization degree achieved through the higher

• for ORR were performed in 1 mol/L KOH solution under air with cyclic potential sweeps between 0.6 and 1.1 V versus RHE at a 50 mV/s sweep rate for 2000 cycles. The electrochemical impedance spectroscopy (EIS) measurements were performed in 1 mol/L KOH, in a frequency range of (0.1–1) × 105 Hz and a

Exfoliation in a low boiling point solvent and electrochemical applications of MoO₃

• Matangi Sricharan,
• Bikesh Gupta,
• Sreejesh Moolayadukkam and
• H. S. S. Ramakrishna Matte

Beilstein J. Nanotechnol. 2020, 11, 662–670, doi:10.3762/bjnano.11.52

• supercapacitors [30][31]. The composite with 5 wt % CB was tested for about 500 cycles (Figure 3e). Initially the specific capacitance was found to increase, which can be attributed to the wetting of the active material in the initial cycles [26]. Electrochemical impedance spectroscopy was used to study the

• and the activation of available sites. Also, the composite shows a capacitance retention up to 94% even after 2000 cycles. Electrochemical impedance spectroscopy (EIS) is used to study the electrochemical series resistance and ideal nature of the capacitor. As shown in Figure 4f, EIS shows a typical

• ) CV curve at different scan rates; (c) capacitance as a function of the scan rate; (d) galvanostatic charge–discharge; (e) cyclic stability and (f) electrochemical impedance spectrum with enlarged view in the inset. Supporting Information Supporting Information File 80: Additional experimental data

Comparison of fresh and aged lithium iron phosphate cathodes using a tailored electrochemical strain microscopy technique

• Matthias Simolka,
• Hanno Kaess and
• Kaspar Andreas Friedrich

Beilstein J. Nanotechnol. 2020, 11, 583–596, doi:10.3762/bjnano.11.46

• impedance spectroscopy (EIS), potentiostatic intermittent titration technique (PITT), galvanostatic intermittent titration technique (GITT), CV). These techniques assume a simultaneous participation of all LFP particles in the electrodes when a “domino-cascade” is presumed to more accurately reflect the

Current measurements in the intermittent-contact mode of atomic force microscopy using the Fourier method: a feasibility analysis

• Berkin Uluutku and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2020, 11, 453–465, doi:10.3762/bjnano.11.37

• with relatively high conductance materials do exist (e.g., FEMTO DHPCA-100, trans-impedance amplifier [48]), which could, for example, record currents in the nanoampere regime at frequencies near 1 MHz. For experiments conducted on materials with significantly lower conductivity, different approaches

• need to be taken. It is possible that the use of several amplifier stages, in contrast to the use of a single trans-impedance amplifier in most conventional C-AFM setups, could improve time resolution [49]. Since the current spectrum is not expected to exhibit arbitrary frequencies, additional lock-in

• capacitive, dielectric, and impedance properties, such that the timescale of the applied bias voltage can strongly influence the result [55][56]. One additional material-related challenge, is that in some materials the measured current is already very small (this is also the case in tunnelling experiments

High dynamic resistance elements based on a Josephson junction array

• Konstantin Yu. Arutyunov and
• Janne S. Lehtinen

Beilstein J. Nanotechnol. 2020, 11, 417–420, doi:10.3762/bjnano.11.32

• higher than for CMOS-based devices. It is universally accepted that the limiting factor for the speed of operation of various superconducting devices is the high-frequency impedance, e.g., originating from kinetic inductance. The effect should be taken into consideration for various cryoelectronic

• impedance was demonstrated to study the QPS phenomena without the undesired impact of Johnson noise typically associated with dissipative elements [12]. The I–V dependence studied in [12] demonstrated clear and expected characteristics at low current, I → 0: the so-called “Bloch nose” (back-bending of I–V

• followed by ultrahigh vacuum deposition of materials was used for the fabrication of the nanostructures. Hybrid QPSJ samples were made of Ti, Al and aluminum oxide [12]. The high-impedance JJs studied in this paper, similar to those from [12], were fabricated from superconducting thin film Al oxidized in

Synthesis and enhanced photocatalytic performance of 0D/2D CuO/tourmaline composite photocatalysts

• Changqiang Yu,
• Min Wen,
• Zhen Tong,
• Shuhua Li,
• Yanhong Yin,
• Xianbin Liu,
• Yesheng Li,
• Tongxiang Liang,
• Ziping Wu and
• Dionysios D. Dionysiou

Beilstein J. Nanotechnol. 2020, 11, 407–416, doi:10.3762/bjnano.11.31

• Information File 1, Figure S1). Generally speaking, the higher the transient photocurrent density, the smaller the electrochemical impedance spectra (EIS) [33][34]. According to the time-resolved PL spectra in Figure 5d, the average fluorescence lifetime of the CuO/tourmaline composite (2.94 ns) was shortened

Implementation of data-cube pump–probe KPFM on organic solar cells

• Benjamin Grévin,
• Olivier Bardagot and
• Renaud Demadrille

Beilstein J. Nanotechnol. 2020, 11, 323–337, doi:10.3762/bjnano.11.24

• -resolution at least as good as 1 µs can be achieved with this setup. The slight overestimation of the pulse amplitude (213 mV instead of 200 mV) originates from an impedance mismatch effect. This has been confirmed by comparing the KPFM loop response (in standard mode) to the dc bias applied from the AWG or

• multiplication stage generating the probe signal and by modifying the electric circuit for fast operation upon electrical pumping with a correct circuit impedance matching. Last, by comparing the results of pp-KPFM and of differential SPV imaging performed on the bare organic layer, an underestimation effect in

• pixel was set to 1 s, preceded by a pre-integration time of 2 s. The open circles represent calculated values obtained by integrating the pump signal over the probe-time window and by applying a correction factor to correct the impedance mismatch. The calculated data have been shifted along the y-axis