Influence of conductive carbon and MnCo₂O₄ on morphological and electrical properties of hydrogels for electrochemical energy conversion

• Sylwia Pawłowska,
• Karolina Cysewska,
• Yasamin Ziai,
• Jakub Karczewski,
• Piotr Jasiński and
• Sebastian Molin

Beilstein J. Nanotechnol. 2024, 15, 57–70, doi:10.3762/bjnano.15.6

• hydrogel structure. The changes are within the range of 79.7–1390.5 kΩ at 0.01 Hz and 3.5–18.6 kΩ at 1 Hz. The trend of the electrochemical impedance spectroscopy (EIS) results shows the capacitive-dominant nature of the hydrogel for all analysed hydrogel-based electrodes. Three different regions were

• electrical properties strongly depend on the conductive carbon concentration (Figure 4d). A similar EIS behaviour was observed in the literature for several different hydrogel-based structures [26][52][53][54]. For comparison, the impedance values of gelatin methacryloyl (GelMA), GO/GelMA, and r(GO/GelMA) at

• were tested for biomedical applications. Nevertheless, they show that the impedance trend that we obtained is similar to that of other hydrogel materials presented in the literature. Additionally, experimental EIS data was modelled with simple electrical equivalent circuit (insert in Figure 4a), where

In situ magnesiothermic reduction synthesis of a Ge@C composite for high-performance lithium-ion batterie anodes

• Ha Tran Huu,
• Ngoc Phi Nguyen,
• Vuong Hoang Ngo,
• Huy Hoang Luc,
• Minh Kha Le,
• Minh Thu Nguyen,
• My Loan Phung Le,
• Hye Rim Kim,
• In Young Kim,
• Sung Jin Kim,
• Van Man Tran and
• Vien Vo

Beilstein J. Nanotechnol. 2023, 14, 751–761, doi:10.3762/bjnano.14.62

• and ionic conductivity, which was further analyzed using rate performance and EIS results. Figure 5b shows the rate performance of the Ge@C electrodes at different specific currents. The common phenomenon of capacity reduction at increasing specific currents is observed in all electrodes. However, the

• conductivity of the additional carbon matrix, indicating the decrease in charge transfer resistance of the composite electrodes. The EIS results were fitted using an equivalent circuit model, including an internal or electrolyte resistance (Re), a charge transfer resistance (Rct), and two constant phase

• . Electrochemical impedance spectroscopy (EIS) was carried out at the open-circuit voltage of the assembled cells after 6 h of resting on a Biologic VSP3 potentiostat. A sinusoidal signal with an amplitude of 10.0 mV and a frequency varying exponentially from 10 mHz to 100 kHz was used. (a) XRD patterns, (b) FTIR

A graphene quantum dots–glassy carbon electrode-based electrochemical sensor for monitoring malathion

• Sanju Tanwar,
• Aditi Sharma and
• Dhirendra Mathur

Beilstein J. Nanotechnol. 2023, 14, 701–710, doi:10.3762/bjnano.14.56

• Brillouin zone, while the G band arises from vibrations in rings of sp2-hybridized atoms inside the GQDs. Electrochemical studies Electrochemical impedance spectroscopy In order to investigate the charge transfer on the electrode surfaces, electrochemical impedance spectroscopy (EIS) was used with the redox

• probe ferrocyanide. In EIS spectra, the semicircle component represents the charge transfer resistance (Rct) at the surface of the electrode. The Nyquist plots of the GQDs/GCE and the bare GCE are shown in Figure 6 in 0.1 M KCl solution containing 0.05 M [Fe(CN)6]3−/4−. The bare GCE electrode exhibits a

• distribution along with log-normal fit, (c) HRTEM image, and (d) AFM image of GQDs. (a) XRD pattern and (b) EDX spectra (inset showing weight and atomic percent of carbon and oxygen) of GQDs. (a) FTIR spectrum and (b) Raman spectrum of GQDs. EIS measurement of 0.1 M KCl containing 0.05 M [Fe(CN)6]3−/4− at the

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

• compositions aligned by DEP [25]. In some of these works, electrochemical impedance spectroscopy (EIS) was used as an effective tool to study the effects of chemical and physical absorption of water on the nanostructured surfaces of active CuO elements of the systems [23][24]. To the best of our knowledge, the

• 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

• applications, the measurements are performed in a RH range from 5% up to 97% and in a T range of 25–55 °C, which covers wider RH and T ranges than previous studies. Equivalent circuit models for the nanowire-based system are developed based on the EIS measurements. Fitting of the cell parameters shows

Evaluation of electrosynthesized reduced graphene oxide–Ni/Fe/Co-based (oxy)hydroxide catalysts towards the oxygen evolution reaction

• Karolina Cysewska,
• Marcin Łapiński,
• Marcin Zając,
• Jakub Karczewski,
• Piotr Jasiński and
• Sebastian Molin

Beilstein J. Nanotechnol. 2023, 14, 420–433, doi:10.3762/bjnano.14.34

• the improvement in the OER of NiFe-GO with the higher Qdep of NiFe and GO resulted mainly from the NiFe structure and the electroactive surface area and the porosity of GO. Electrochemical impedance spectroscopy (EIS) was performed in order to determine the charge transfer resistance (Rct) of the

• specific catalysts. The EIS spectra are presented in Supporting Information File 1 (Figure S4). Rct values of 0.43, 0.50, 0.57, and 0.65 Ω were determined for NiFe-GO, CoNiFe, CoNiFe-GO, and NiFe, respectively. A decrease in Rct is associated with more efficient reaction rates for the OER. The EIS results

• RHE with a scan rate of 5 mV·s−1. The EIS spectra were recorded in the frequency range from 10 kHz to 1 Hz at 1.6 V vs RHE and amplitude of 10 mV. In order to determine Rct, EIS spectra were fitted with a simple Randles model with the solution resistance, charge transfer resistance, and the constant

Photoelectrochemical water oxidation over TiO₂ nanotubes modified with MoS₂ and g-C₃N₄

• Phuong Hoang Nguyen,
• Thi Minh Cao,
• Tho Truong Nguyen,
• Hien Duy Tong and
• Viet Van Pham

Beilstein J. Nanotechnol. 2022, 13, 1541–1550, doi:10.3762/bjnano.13.127

• with previous publications [50][51][52]. Figure 5 shows the results of electrochemical impedance spectroscopy (EIS), that is, Nyquist and Mott–Schottky plots of the materials, which give information about the charge transfer mechanism at the interface. In Figure 5a, the Nyquist plots of the samples all

• consistent with the previous results from EIS analysis and the Mott–Schottky results (Figure 5). The PEC activity of MoS2/TNAs in this study is higher than that of MoS2/TNAs synthesized by using a PVA binder agent in [36]. However, the direct combination of g-C3N4 with TNAs at a relatively high fabrication

• is in agreement with the EIS results in Figure 5a, where the arc radius of the Nyquist plot of MoS2/TNAs was the smallest, indicating that MoS2/TNAs effectively decreased the resistance of the TNAs and, thus, speeded up the charge transfer on the photoelectrode. These arguments are consistent with

A TiO₂@MWCNTs nanocomposite photoanode for solar-driven water splitting

• Anh Quynh Huu Le,
• Ngoc Nhu Thi Nguyen,
• Hai Duy Tran,
• Van-Huy Nguyen and
• Le-Hai Tran

Beilstein J. Nanotechnol. 2022, 13, 1520–1530, doi:10.3762/bjnano.13.125

• electrode [35]. Based on the cyclic voltammetry results, it could be suggested that the TiO2@MWCNTs electrode is superior regarding photoelectrochemical application compared to TiO2 and MWCNTs electrodes. Electrochemical impedance spectroscopy (EIS) is applied to characterize the electron-transfer property

• conductivity of TiO2 [37]. Table 1 shows the EIS parameters obtained from fitting the measured results with equivalent circuits. The R1 values illustrate a low electrical resistance of the 0.1 M KCl solution, while the R2 values show that the TiO2 electrode has the highest resistance among the prepared

• not found in the TiO2 and TiO2@MWCNTs electrodes [41]. The EIS spectrum shows that the Voigt circuit is found to fit the TiO2 electrode. In contrast, the EIS spectrum of the TiO2@MWCNTs electrode, including two semicircle parts, demonstrates different responses of the electrode at low and high

Rapid and sensitive detection of box turtles using an electrochemical DNA biosensor based on a gold/graphene nanocomposite

• Abu Hashem,
• M. A. Motalib Hossain,
• Ab Rahman Marlinda,
• Mohammad Al Mamun,
• Khanom Simarani and
• Mohd Rafie Johan

Beilstein J. Nanotechnol. 2022, 13, 1458–1472, doi:10.3762/bjnano.13.120

• using electrochemical impedance spectroscopy (EIS) measurements. In 2.0 mM [Fe(CN)6]3−/4− containing 0.2 M KCl as the supporting electrolyte, the Nyquist plots of the SPCE, Gr/SPCE, AuNPs/SPCE, and AuNPs/Gr/SPCE are shown in Figure 3d. The inset is the equivalent circuit indicating the charge transfer

• than that of individual nanomaterial-modified SPCEs, representing a limitation of electron transfer through the electrode–solution interface [56] for different electrode surfaces. The EIS plots for the modified SPCEs surfaces also reveal that the electrode–solution interfacial charge transfer process

• group in 2008 reported optimisation of DNA immobilisation on gold electrodes for label-free detection by EIS [63]. Another group published a report for label-free DNA detection using the EIS technique with PNA probes, and they discovered that detection can be greatly improved when using uncharged

LED-light-activated photocatalytic performance of metal-free carbon-modified hexagonal boron nitride towards degradation of methylene blue and phenol

• Nirmalendu S. Mishra and
• Pichiah Saravanan

Beilstein J. Nanotechnol. 2022, 13, 1380–1392, doi:10.3762/bjnano.13.114

• . The Mott–Schottky (MS) analysis was performed at a frequency of 1 kHz while the electrochemical impedance spectroscopy (EIS) studies were conducted at 0 V DC under a frequency range of 105 to 100 Hz. The open circuit potential as a function of time (OCPT) was performed under alternating light and dark

• reflectance for the specified materials, respectively. It was observed that the MBN had an enhanced LHE (90%) in comparison to that of HBN with zero activity in the visible range, 85% (MBN-50), and 70% (MBN-25). Electrochemical analysis The EIS analysis provides further evidence on the enhanced performance of

Near-infrared photoactive Ag-Zn-Ga-S-Se quantum dots for high-performance quantum dot-sensitized solar cells

• Roopakala Kottayi,
• Ilangovan Veerappan and
• Ramadasse Sittaramane

Beilstein J. Nanotechnol. 2022, 13, 1337–1344, doi:10.3762/bjnano.13.110

• fabricated QDSCs. J–V curve of the fabricated QDSCs. Electrochemical impedance (EIS) parameter values of the fabricated QDSCs. The values of Rs and τs and photovoltaic parameters of the synthesized QDSC in comparison with those of a Zn-Ag-In-S QD-sensitized QDSC and a Zn-Ag-In-Se QD-sensitized QDSC

Spindle-like MIL101(Fe) decorated with Bi₂O₃ nanoparticles for enhanced degradation of chlortetracycline under visible-light irradiation

• Chen-chen Hao,
• Fang-yan Chen,
• Kun Bian,
• Yu-bin Tang and
• Wei-long Shi

Beilstein J. Nanotechnol. 2022, 13, 1038–1050, doi:10.3762/bjnano.13.91

• ) with BaSO4 as a reference. The photoluminescence spectrum (PL) was obtained from a luminescence spectrometer at an excitation wavelength of 446 nm (RF-530IPC, Shimadzu, Japan). The photocurrent response and electrochemical impedance spectra (EIS) were measured by an electrochemical workstation

• suggests that the formation of the heterojunction can promote charge transfer on the interface between MIL101(Fe) and Bi2O3. Furthermore, the interfacial charge transfer behavior of the BOM-20 composite is also confirmed by EIS. In Figure 5d, BOM-20 exhibits the smallest arc radius, meaning that BOM-20

• possesses the lowest resistance and the highest separation rate of electron–hole pairs on the interface of MIL101(Fe) and Bi2O3 [57], which is consistent with the results from PL spectra and photocurrent analysis. In summary, PL spectra, photocurrent responses, and EIS analysis all indicated that Bi2O3

Electrocatalytic oxygen reduction activity of AgCoCu oxides on reduced graphene oxide in alkaline media

• Iyyappan Madakannu,
• Indrajit Patil,
• Bhalchandra Kakade and
• Kasibhatta Kumara Ramanatha Datta

Beilstein J. Nanotechnol. 2022, 13, 1020–1029, doi:10.3762/bjnano.13.89

• polarization curves of various catalysts in O2-saturated 0.1 M KOH electrolyte at 1600 rpm and a sweep rate of 10 mV·s−1. (b) Corresponding Tafel plots. (c) Mass activity obtained at 0.7 V for all active catalysts and (d) Nyquist plots (the inset shows high-frequency EIS curves). (a) TEM and (b) HRTEM images

Hierarchical Bi₂WO₆/TiO₂-nanotube composites derived from natural cellulose for visible-light photocatalytic treatment of pollutants

• Zehao Lin,
• Zhan Yang and
• Jianguo Huang

Beilstein J. Nanotechnol. 2022, 13, 745–762, doi:10.3762/bjnano.13.66

• , respectively. The transient photocurrent responses and electrochemical impedance spectroscopy (EIS) Nyquist plots (frequency: 0.01 Hz−100 kHz, alternate current: 5 mV) of a given sample were obtained on a CHI 760D (Shanghai, China) electrochemical workstation using a three-electrode system. The Pt plate (1.0

• performs analog results as compared to the PL characterization, suggesting the most effective separation and transfer of photogenerated carriers of the 70%−Bi2WO6/TiO2-NT and 90%−Bi2WO6/TiO2-NT nanocomposites. EIS Nyquist plots of samples are usually employed to determine the transfer resistances and

• efficiencies of the photogenerated charges of the corresponding electrodes. As displayed in Figure 10b, the circular arc radii in the EIS Nyquist plots of all the Bi2WO6/TiO2-NT nanocomposites are smaller than those of the pure Bi2WO6 powder sample apart from the 30%−Bi2WO6/TiO2-NT nanocomposite. This

A nonenzymatic reduced graphene oxide-based nanosensor for parathion

• Sarani Sen,
• Anurag Roy,
• Ambarish Sanyal and
• Parukuttyamma Sujatha Devi

Beilstein J. Nanotechnol. 2022, 13, 730–744, doi:10.3762/bjnano.13.65

• Technologies, USA), which was connected by a three-electrode system, including a modified and/or unmodified GCE as the working electrode, a saturated Ag/AgCl as the reference electrode (RE), and a platinum wire as the counter electrode (CE). The electrochemical impedance spectroscopy (EIS) study of the

• nonenzymatic electrochemical nanosensor based on ERGO for rapid detection of PT. The electrochemical parameters were optimized to achieve the highest performance of the ERGO-modified electrode, and the structure was characterized by Raman, XRD, XPS, TEM, FESEM, and EIS techniques. Square-wave voltammetry was

Influence of thickness and morphology of MoS₂ on the performance of counter electrodes in dye-sensitized solar cells

• Lam Thuy Thi Mai,
• Hai Viet Le,
• Ngan Kim Thi Nguyen,
• Van La Tran Pham,
• Thu Anh Thi Nguyen,
• Nguyen Thanh Le Huynh and
• Hoang Thai Nguyen

Beilstein J. Nanotechnol. 2022, 13, 528–537, doi:10.3762/bjnano.13.44

• electrocatalytic behavior of the MoS2 CEs was carried out by using the EIS technique under dark conditions using full cells assembled from different MoS2/FTO CEs or a Pt/FTO CE. The Nyquist plots for these cells exhibited two semicircles as presented in Figure 6. The first semicircle in the high-frequency region

• is associated with the reduction of I3− at the cathode (CE/electrolyte), while the second one in the low-frequency region is attributed to electron transport in the TiO2 film in the back reaction at the TiO2/electrolyte interface (TiO2/dye/electrolyte). EIS data were fitted using an equivalent

• (EIS) of the fabricated DSSCs was carried out using an Autolab 302 N equipped with a FRA 32M module. The EIS measurements were carried out at open-circuit voltage with an alternating voltage amplitude of 10 mV under dark conditions in a frequency range between 0.01 Hz and 100 kHz. The efficiency of the

A non-enzymatic electrochemical hydrogen peroxide sensor based on copper oxide nanostructures

• Irena Mihailova,
• Vjaceslavs Gerbreders,
• Marina Krasovska,
• Eriks Sledevskis,
• Valdis Mizers,
• Andrejs Bulanovs and
• Andrejs Ogurcovs

Beilstein J. Nanotechnol. 2022, 13, 424–436, doi:10.3762/bjnano.13.35

• EIS curve and the corresponding equivalent circuit are presented. The absence of characteristic semicircles formed by RCs by the circuit elements indicates a low charge transfer resistance and the predominance of Warburg diffusion over other processes in the electrochemical system. Figure 3f shows an

• unambiguous change in the EIS curves as a reaction to the addition of small concentrations of H2O2 to the solution. The active surface area of an electrode can be calculated using the Randles–Sevcik equation [83][84][85], which at 25 °C is: where Ip represents the redox peak current (A), n is the number of

• cycles (n = 10). Measurements were carried out in 0.1 M NaOH solution containing 5 mM H2O2. (d) EIS analysis (frequency range from 1 Hz to 100 kHz at an applied signal voltage of about 0.3 V). Measurements were carried out in 0.1 M NaOH solution containing 0–200 μM H2O2. SEM images of CuO nanostructures

Tin dioxide nanomaterial-based photocatalysts for nitrogen oxide oxidation: a review

• Viet Van Pham,
• Hong-Huy Tran,
• Thao Kim Truong and
• Thi Minh Cao

Beilstein J. Nanotechnol. 2022, 13, 96–113, doi:10.3762/bjnano.13.7

• spectroscopy (EIS) data, and the nanosecond-level time-resolved fluorescence decay spectra (Figure 11) demonstrated that the SnO2/NCDs/ZHS nanohybrid achieved low charge carrier recombination, high photoactivity, and excellent photoinduced charge transfer to the surface of the semiconductor. This study enables

• of SnO2. Moreover, enhanced visible light response and enhanced charge separation in the sample with GQDs have been observed (Figure 13c). The EIS measurements (Figure 13d) indicated that the diameter of the arc radius of SnO2/GQDs (1%) is much smaller than that of SnO2, confirming that the GQDs

• generation architectural structure of heterojunctions toward visible-light-driven NO degradation”, article no. 117510, Copyright (2021), with permission from Elsevier. This content is not subject to CC BY 4.0. (a) Surface photovoltage spectroscopy, (b) transient photocurrent responses, (c) EIS Nyquist plots

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

• surface reaction sites before recombination leading to hydrogen evolution. These results are consistent with PL spectroscopy and EIS results, revealing a better separation and charge transfer, respectively, after chlorine doping. Moreover, it was revealed that chlorine doping affected the CB shift to a

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

• equals almost 90°. This corresponds to a capacitive behavior of the electrode material. After cycling, the slope angle changes to almost 45°, which is typically associated with a semi-infinite diffusion behavior [25]. Further analyses of the EIS results yield that the value of Rct has drastically

Exploring the fabrication and transfer mechanism of metallic nanostructures on carbon nanomembranes via focused electron beam induced processing

• Christian Preischl,
• Linh Hoang Le,
• Elif Bilgilisoy,
• Armin Gölzhäuser and
• Hubertus Marbach

Beilstein J. Nanotechnol. 2021, 12, 319–329, doi:10.3762/bjnano.12.26

• SEM was used as ionization source at an energy of 15 keV and a beam current of 3.0 nA. Spectra were recorded with a hemispherical electron energy analyzer (EA125, Omicron Nanotechnology) and EIS 2.4.24.97 (Omicron Nanotechnology). Data processing was performed with Igor Pro 6.22A (Wavemetrics). The

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

• mode, which is indicative of a large amount of defect centers. The existence of defect centers affects the vibration mode and eventually causes a blueshift, as shown in Figure 1d. Finally, the electrical properties obtained via CV and EIS can also be correlated with the defect structures when the

• . Therefore, different electrical components contribute to the equivalent circuit of the EIS results. Warburg element, charge transfer resistance (Rct), and equivalent series resistance (ESR) are some of the elements that contribute to the resistive behavior [11]. At this point, we highly suggest to the

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

• . The ohmic resistance (RΩ) and charge-transfer resistance (Rct) values of the fresh sample and of the sample after the first charge and first discharge were obtained by analyzing the EIS curves (Table 2). The value of RΩ of NiFe-PBA/PP-T after the first discharge was higher than that of the fresh

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

• electrochemical behavior [49]. EIS is one of the most accurate methods to analyze the dynamic process of diffusion in the electric double layer of an electrode. It is also commonly used to study the high energy storage capacity mechanism in electrodes. The general EIS spectrum is mainly composed of two parts: the

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

• can be traced to the best conductivity among all the CTF-based electrocatalysts as investigated by EIS tests. Consequently, we believe that CTFs are potential candidates for electrochemical OER and offer room for improvement. In the future, we anticipate that this study should inspire further

• 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

• 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

• ) galvanostatic charge–discharge profile of the 5 wt % CB composite; (e) capacitance retention of the 5 wt % CB composite; (f) EIS of the composites. Supercapacitor characterization of a MoO3/5 wt % CB composite in two-electrode configuration. (a) CV curve of the symmetric capacitor at a scan rate 5 mV·s−1; (b