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•An electrochemical sensing method was developed for the estimation of strontium ions.•Explored the electrochemical behavior of strontium ions in the presence and absence of rosemary ...by the cyclic voltammetry using 18 Karat gold working electrode.•Dissolved oxygen estimation for different solutions was measured.•Molecular docking analysis suggested potential therapeutic effects of rosemary (carnosol and carnosic acid) against COVID-19.•The antibacterial activities were studied for rosemary.
This work presents an electrochemical sensing for the estimation of strontium ions by cyclic voltammetry and studies its electrochemical behavior in the presence and absence of rosemary using 18 an Karat Gold working electrode in 0.1 M KBr at 295.15 K. The potential therapeutic effects of carnosol and carnosic acid against COVID-19 were explored through molecular docking analysis, suggesting their antiviral effects. The results showed that the obtained cyclic voltammograms showed well-defined redox peaks, and the peak current was found to increase linearly with increasing strontium chloride concentration. Rosemary has been shown to have antioxidant properties, which affect the redox behavior of strontium ions, leading to changes in the peak current and potential observed. SrCl2 solution has higher oxygen solubility and is useful in various industries. Additionally, plant extract showed inhibition of the growth of Gram-positive and Gram-negative bacteria due to its antibacterial activity. Overall, this research offers a promising electrochemical approach for measuring strontium ions and, the antibacterial activity of the Rosemary extract and reveals the potential therapeutic benefits of it against COVID-19.
Herein we report, a simple operable, sensitive, and highly selective, voltammetric method for the determination of iodide (Iˉ) using chitosan modified multiwall carbon nanotube paste electrode ...(chit-MWCNTPE). It is established that chit-MWCNTPE exhibited a pronounced response toward Iˉ oxidation. The peak potential of Iˉ is recorded at 0.69 V vs SCE. The conditions such as scan rate (V.s−1), accumulation time (ta), and pH are thoroughly optimized for the voltammetric determination of Iˉ. A wide range linear response is observed between oxidation peak current and Iˉ concentration (0.1–100 μM). The limit of detection (LOD) for Iˉ on chit-MWCNTPE is found to be 0.03 μM. The developed method is highly selective for Iˉ detection in the presence of various interfering ions. The method is successfully applied for the determination of Iˉ in urine samples. The method has high selectivity for Iˉ detection at comparably low potential as well as amiable LOD and Linear range.
•Chitosan modified multiwall carbon nanotube paste electrode was studied selective determination of Iodide.•Chit-MWCNTPE material was characterized by SEM, EDX, XRD and FT-IR.•The sensitivity and LOD of Chit-MWCNTPE for iodide was found to be 328.8 μA/mM cm−2 and 0.03 μM, respectively.
In search for the probability of p-n junction in the quasi-solid (QS) phase in the multi-semiconductor specimen (MSS) altogether with the development of the DSSC electrolyte optimization technique, ...there are three major things to be considered: 1) the hypothesis for a theoretical redox-conductivity (Ip−σ) correlation on the better understanding of advanced cyclic voltammetry (CV) analysis using a mathematical axiom correlation method, 2) the concept of p-n junction possibility based on the solid-phase (SP) hypothetical projection, and 3) the observational and optimization for x-TiO2/Cs/KI-I2.
To prove the p-n junction existence in a QS-MSS, we develop a series of methods by using advanced analysis of voltammogram, which are 1) defining the chitosan as a conductive polymer to a certain extent, 2) understanding the influence of different wt% x-TiO2 on the redox activity of QS-MSS, and 3) the different crystal system of TN(10)†,‡ that are anatase-rutile (a-r) and rutile-anatase (r-a) dominant phase are influencing the Ip. Moreover, the analyses consist of a series of modified-dimensionless parameter, ψ, to define the modified-diffusional coefficient, Dx2, definition and electronical transferal rate, k0, as well. Furthermore, the crucial observation is by looking at the valence and conduction band (vb-cb) for each sample, respectively, to determine the position toward the hypothetical projection in the DSSC system later. Moreover, we found that a hypothetical development on the Ip−σ modified function is needed. Also, the use of the vb-cb value is crucial to project a unified rule of p-n junction theory approximation from electrolyte to dye.
We report a facile method for obtaining extremely high surface area and uniformly porous carbon nanofibers for supercapacitors. Blends of polyacrylonitrile and sacrificial Nafion at different ...compositions have been electrospun into non-woven nanofiber mats with diameters in the range of 200–400 nm. Electrospun nanofiber mats are then subjected to carbonization to obtain porous carbon nanofibers (CNFs) as polyacrylonitrile converts to carbon and Nafion decomposes out creating intra-fiber pores. Resultant porous CNFs exhibit specific surface area of up to 1600 m2 g−1 with a large fraction of mesopores (2–4 nm). No additional chemical or physical activation process was used. We demonstrate the tunability of the pore sizes within CNFs by varying the amount of Nafion. The non-woven fiber mats of porous CNFs are studied as free-standing electrode materials for supercapacitors eliminating the need for polymeric binding agents. Electrochemical measurements showed large specific gravimetric and volumetric capacitances of up to 210 F g−1 and 60 F cm−3 in 1 M H2SO4 at a high cyclic voltammetry scan rate of 100 mV s−1 due to the large fraction of mesopores. These materials retain 75% performance at a large current density of 20 A g−1 indicating excellent power handling capability.
► Fabrication of free-standing porous carbon nanofibers (CNFs) using electrospinning. ► We demonstrate interconnected pore structure inside carbon nanofibers using TEM. ► Porous CNFs exhibit 1600 m2 g−1 specific surface with large fraction of mesopores. ► Porous CNFs exhibit 210 F g−1 at 1 A g−1 current and retain 75% capacitance at 20 A g−1. ► Porous CNFs exhibit high power due to hierarchical pore structure.
Recent years have witnessed significant advances in all-solid-state lithium batteries (ASSLBs). However, soft breakdown hidden in ASSLBs has been overlooked in most previous research. Moreover, ...existing assessment criteria are insensitive to detecting soft breakdown. Here, we first discuss the current status of ASSLBs and highlight the challenges of evaluating the soft breakdown phenomenon with the existing evaluation method. A simple but effective strategy—cyclic voltammetry—is then proposed to diagnose soft breakdown in all-solid-state symmetric cells. To establish a standard testing protocol, several critical parameters that have not been well emphasized thus far, including areal capacity, thickness, and porosity of solid electrolytes, are numerically analyzed to understand their significant effect on the energy density of practical all-solid-state pouch cells. With these understandings, we establish a definitive testing benchmark with the aim of guiding the research efforts toward in-depth scientific understanding and practical engineering design.
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To develop next-generation energy storage systems with high energy density and unprecedented safety, all-solid-state lithium batteries (ASSLBs) that replace conventional flammable organic liquid electrolytes with solid-state electrolytes (SSEs) have been revived in academia and industry. However, soft breakdown hidden in ASSLBs has not been well realized, which generally leads to unreliable conclusions and significantly retards ASSLB development. To exclude this phenomenon, we propose a simple but effective method—cyclic voltammetry—to diagnose the soft breakdown in ASSLBs. Moreover, a low-frequency electrochemical impedance analysis is employed to quantify the soft breakdown phenomenon. Finally, a standard testing protocol is suggested, which could help this community obtain reliable and comparable results in the future. This work's fundamental understanding and established assessment metrics are also applicable to other metal-based all-solid-state batteries.
Soft breakdown hidden in ASSLBs has been overlooked in most previous research. Here, we propose a simple but effective strategy—cyclic voltammetry—to diagnose soft breakdown in all-solid-state batteries. Moreover, low-frequency electrochemical impedance spectroscopy is employed to quantify the soft breakdown. With this understanding, we establish a standard testing protocol, which could be used to unify future research endeavors if adopted. This work provides new insights into ASSLBs and establishes assessment metrics for this community.
In this study, we demonstrate that the utilization of modeling CV offers a promising new quantitative approach for elucidating charge storage mechanisms in two categories: diffusion-controlled and ...capacitive-controlled processes. Furthermore, we compared the results with Dunn's and Trasatti's methods, highlighting discrepancies and limitations in these approaches. Our research underscores the importance of constructing models that accurately represent the entire CV system, enabling a deeper understanding of charge storage mechanisms. Consequently, our findings pave the way for the advancement of more efficient and effective energy storage technologies.
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•CV data were simulated and compared with conventional relationships.•Highlighting the advantages and limitations of using conventional approaches.•Studying the impact of resistance and CPE exponent on charge storage mechanisms.•Emphasizing the significance of further developing CV models.
As electrochemical energy storage continues to gain importance, researchers have been exploring novel materials and electrode designs to enhance performance. While these innovations have significantly improved the performance of energy storage devices, the specific mechanisms responsible for their success remain unclear. One powerful tool for gaining insights into how modifications to the electrode can enhance cell performance is cyclic voltammetry (CV). However, interpreting CV data can be challenging, and simple analytical relations are often inadequate for accurate assessment. Moreover, different analytical methods can yield conflicting results, leading to confusion within the research community and hindering progress in the field. To address these challenges, our study aims to investigate the contributions of surface and diffusion-controlled processes to charge storage in supercapacitor applications. We will employ conventional methods to examine how these processes can lead to the misinterpretation of CV data and identify the advantages and limitations of different analytical approaches. Our research underscores the importance of developing models that faithfully replicate the system of interest to gain insights into charge storage mechanisms. By identifying these key factors, our findings could pave the way for the development of more efficient and effective energy storage technologies.
In article number 2007826, Morgan Stefik and co‐workers determine unambiguous nanostructure‐property relationships using a series of nanoscale T‐Nb2O5 architectures that vary by a single spatial ...variable at a time by using persistent micelle templates. The departure of lithiation behavior from intercalation pseudocapacitance with surface‐limited kinetics depend sensitively upon the architecture's intercalation length scale. Identifying such nanostructure–performance relationships enables tailored architecture designs that are “nano‐optimized” to specific needs.
This study presents the development of an efficient and cost-effective voltammetric sensor for the individual and simultaneous determination of uric acid (UA), tryptophan (Try) and hypoxanthine (HX), ...the three important biomarkers in the human body. The sensor consists of glassy carbon electrode (GCE) modified with the conducting layer of poly(L-Arginine) (p-Arg) prepared by the electropolymerisation of L-Arginine using cyclic voltammetry. p-Arg modified GCE (p-Arg/GCE) provided well-resolved and improved electrooxidation responses for UA, Try, and HX due to the greater electrocatalytic activity and fast electron transfer ability of the polymer layer. The fabricated sensor was characterised using Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), Atomic Force Microscopy (AFM), Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR), Electrochemical Impedance Spectroscopy (EIS) and electroactive surface area calculations. Under optimal analytical conditions, determination of the three analytes was possible over wide linear ranges with the limit of detection of 1.97 × 10
−8
M, 4.43 × 10
−8
M, and 8.44 × 10
−9
M, respectively for UA, Try, and HX. Practical utility of the sensor was successfully verified in synthetic urine and blood serum samples and determination of Try and HX was carried out in dietary supplements and commercially available samples of tea and coffee, respectively.
Highlights
A sensitive voltammetric sensor was developed using poly L-Arginine modified GCE.
L-Arginine modified GCE shows high electrocatalytic and electron transfer activity.
The sensor allowed the simultaneous determination of UA, Try and HX.
Practical utility of the sensor was verified in artificial serum and urine samples.
Applicability of the sensor for Try sensing was verified in dietary supplement.
The sensor exhibits low detection limits for the analytes.
Nanosheet like nickel metal organic frameworks (Ni-MOFs) have been synthesized using solvothermal route at room temperature. Functionalized multiwalled carbon nanotubes (MWCNTs) have been embedded ...into these MOFs through equilibration to prepare the composite. The composite (Ni-MOFs/MWCNTs) has been used as a modifier in sensor fabrication on glassy carbon electrode surface and successfully applied in dopamine measurement through cyclic voltammetry and square wave voltammetry techniques. The composite has exhibited enhanced electrochemical performance with a very low detection limit of 0.017
μ
M. The protocol showed wide linearity in the concentration range 2–200
μ
M with a sensitivity of 17.14
μ
A
μ
M
−1
cm
−2
. The proposed electrochemical platform exhibited high sensitivity and selectivity in dopamine sensing which has been successfully applied to real sample matrices like human blood serum and injection.
Highlights
Ni-MOFs/MWCNTs composite has been synthesized using simple solvothermal route at room temperature
The composite has been characterized by SEM, FTIR, XRD, TGA and BET analysis
The fabricated sensor exhibited wide linearity with a very low limit of detection of 0.017
μ
M.
It has been successfully applied to measure trace level dopamine from real sample matrices like dopamine hydrochloride injection and blood serum under optimized conditions.
•The chitosan/rGO/MnO2 based working electrode is able to provide an increase in sensor work activity.•Adding MnO2 in chitosan film could be potentially for sensor material to detect at the lowest ...concentration.•Sensing properties increases with increasing variation of MnO2.
Cholesterol detection needs to be carried out to detect early symptoms of dangerous diseases such as heart disease. The process of detecting cholesterol in the human blood requires a sensitive detection tool in order to produce accurate values. This paper reports the performance of chitosan thin films modified with reduced graphene oxide (rGO) and manganese dioxide (MnO2) as the sensitive layer of working electrodes in detecting cholesterol. The electrode substrate is a copper-screen printed electrode (copper-SPE) which was patterned into 5 mm of sensitive area. The chitosan and chitosan-reduced graphene oxide (rGO) matrices were deposited on the top of working electrodes. The characterization of chitosan, chitosan/rGO, and chitosan/rGO/MnO2 thin films was performed using AFM, FE-SEM, and FTIR. The electrochemical sensing properties of modified working electrode were observed using an electrochemical method of cyclic voltammetry (CV). The novelty of this research is the utilization of chitosan/rGO/MnO2 thin film-based working electrode for detecting cholesterol. The testing results indicated that the sensitivity of the modified working electrodes increased when working electrodes based on chitosan/rGO/MnO2 thin film were used for cholesterol detection compared to the working electrodes based on the chitosan thin film. It was proven from the sensitivity of working electrodes based on chitosan/rGO/MnO2 thin film which gave the lowest value of 3.21 × 10−5 µA/µM as well as the ability of working electrodes based on chitosan/rGO/MnO2 thin film which worked at limit of detection (LoD) 0.26 µM/L and limit of quantification (LoQ) 0.87 µM/L. Based on the sensitivity, LoD, and LoQ values, the chitosan/rGO/MnO2 modified electrodes can be used as working electrodes to measure cholesterol concentration in blood.
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