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We report a bioinspired approach to tune surface nanostructures by soft‐template electropolymerization in micellar conditions. Monomers highly favoring π‐stacking interactions are particularly interesting for favoring the polymer deposition in one direction. Here, original triphenylamine‐based monomers di‐substituted by thiophene and carbazole are investigated. Conjugated building blocks monomers are tested to favor deposition vs polymerization, even if the monomers are not perfectly planar. The carbazole derivatives have a much higher electrodeposition capacity than the thiophene derivatives, which is unexpected if thiophene and carbazole are taken alone. Moreover, in all electrodeposited films, monomer seems to be present as shown by cyclic voltammetry experiments, confirming previous works. The amount of monomer vs oligomers is highly dependent on the investigated monomer. For the resulting surface structures, hollow spheres and nanoribbons are particularly formed with some investigated monomers by cyclic voltammetry while nanotubes are observed at constant potential. The formation of nanotubes indicates a polymer growth more favored in one direction. These surfaces are less hydrophobic (water contact angle up to 111.5°) compared to films with spherical nanoparticles but these results can be explained only by the presence of air inside the surface roughness. [ABSTRACT FROM AUTHOR]

We synthesized some novel isoxazole azo derivatives using conventional methods and studied their linear, non‐linear optical properties and antioxidant activity. UV‐Vis spectroscopy revealed absorption bands ranging from 310–470 nm for the obtained compounds. Compounds 3 c and 3 b, for example, showed a large redshift and solvatochromic behavior. NLO analysis results show that compounds exhibit a greater NLO response than the magnitude of urea done by the DFT method. The electrochemical properties of compounds are studied using cyclic voltammetry and results are used for calculation of HOMO and LUMO experimentally. The antioxidant activity of the synthesized azo dyes displayed that 3 c has excellent antioxidant activity with the highest percentage (71.54605 %) of radical inhibition as compared to reference standard Vit‐C. Molecular docking analysis shows that compounds have a strong binding affinity in the range of −7.0 to −4.6 kcal/mol compared to Vit‐C, which has a binding affinity of −3.6 kcal/mol. The sun protection factor performance was determined by UV‐Vis spectroscopy, and results show that compounds are most effective, exhibit a remarkable SPF value, and offer superior sun protection by absorbing UV rays. [ABSTRACT FROM AUTHOR]

AbstractThis study reports the design and development of a disposable amperometric biosensor for the determination of L-glutamate. Glutamate oxidase (GlOx) was immobilized onto a screen-printed carbon electrode (SPE) modified with poly-L-Aspartic acid (PAsp), carbon quantum dots (CQD), and platinum nanoparticles (PtNP) for the construction of the biosensor. The surface composition of the modified SPE was optimized using the one variable at a time method. The morphological properties of the biosensor were characterized by scanning electron microscopy and energy-dispersive X-ray spectroscopy. The electrochemical behavior of the modified electrodes was studied by cyclic voltammetry. Under the optimized experimental conditions the linear working range, detection limit and sensitivity of the GlOx/PtNP/CQD/PAsp/SPE were found to be 1.0 − 140 µM, 0.3 µM and 0.002 µA µM−1, respectively. The GlOx/PtNP/CQD/PAsp/SPE biosensor also exhibited good measurement repeatability. The as-developed biosensor was applied for the determination of L-glutamate in spiked serum samples and the average analytical recovery of added glutamate was 98.9 ± 3.9%. [ABSTRACT FROM AUTHOR]

In the current study, multi-layer graphene (MLG) and reduced graphene oxide (rGO) were effectively synthesized and characterized by several techniques, including FT-IR, XRD, TGA, CHNS/O Analyzer, Raman spectroscopy, UV–Vis spectroscopy, TEM, and SEM. The electrochemical hydrogen storage (EHS) capacity was measured through cyclic voltammetry (CV), galvanostatic charge/discharge (GCD), and electrochemical impedance spectroscopy (EIS). High-quality graphene (I D /I G < 0.16), obtained from the simple liquid phase exfoliation method, exhibited a remarkable hydrogen storage capacity, reaching up to 200 F g−1 which equals 0.1 wt%. Furthermore, MLG outperforms rGO in terms of coulombic efficiency, achieving 100% in 10 cycles as opposed to rGO's 50% under identical conditions. This study presents the first-ever EHS using a new method that shows promising results. [Display omitted] • The prominent parameters in electrochemical hydrogen storage were examined. • MLG (200 F g−1) outperformed rGO (25 F g−1) electrochemically. • MLG exhibited a discharge capacity 53 times higher than commercial one. • MLG reached 200 F g−1 without metal loading. • The LPE method was determined to have considerable potential in EHS. [ABSTRACT FROM AUTHOR]

Electric trains equipped with efficient electric motors and powered by high-capacity hydrogen fuel cells are a choice of the global transportation industry to accelerate the global transition to a low-carbon transportation system. The operation of distinct vehicle types in varying geographical regions is characterized by unique features. Concurrently, the continually fluctuating demand for electricity necessitates the utilization of fuel cells in conjunction with energy storage devices. Thus, this study centers on examining the role of the PEMFC-supercapacitor direct hybridization system within the authentic driving profile of the subway in the Bangkok metropolitan region. The supercapacitor within the hybridization system serves as an energy management device, enhancing the durability of fuel cells when subjected to diverse load demands associated with train propulsion. In order to validate this hypothesis, an MRT (Mass Rapid Transit) protocol was formulated to emulate and serve as the load demand for the investigation, and then the PEMFC-supercapacitor direct hybridization system was operated using the created profile. Subsequently, the hybridization system undergoes electrochemical characterizations and fuel cell performance tests for diagnostic purposes. Empirical findings validated that the supercapacitor operates as a filter, generating a stable voltage response to varying load requirements, and possesses the capability to assimilate energy originating from regenerative braking. The integration of supercapacitors in stabilizing the operational parameters of proton exchange membrane fuel cells (PEMFCs) has markedly prolonged their operational lifespan. This assertion is substantiated by voltage signal analysis, which demonstrated a negligible increase in surface resistance of merely 0.23%, as depicted by Nyquist plots. Furthermore, cyclic voltammetry revealed that the system attained a peak electrochemical surface area (ECSA) of 0.0089 (106 cm2/mg of Pt). The information presented in this article constitutes data that has been minimally explored in existing research. Specifically, the study concentrates on the practical driving pattern of electric trains. Consequently, experimental results were deemed advantageous for the advancement of heavy-duty electric vehicles. [Display omitted] • Exploring the relationship between the utilization of an energy storage device as a SC and energy generation as a PEMFC. • Establishing a connection between the authentic current profile of an MRT metro system and an accelerated stress test. • Examining the electrochemical reactions within fuel cells, drawing upon operational data from the transportation sector. [ABSTRACT FROM AUTHOR]

A nanocomposite of CaO:MgAl2O4 was synthesized through a straightforward and cost-effective sol–gel method. The investigation of the novel CaO:MgAl2O4 nanocomposite encompassed an examination of its morphological and structural alterations, as well as an exploration of its photocatalytic activities and electrochemical characteristics. XRD analysis revealed a nanocomposite size of 24.15 nm. The band gap, determined through UV studies, was found to be 3.83 eV, and scanning electron microscopy (SEM) illustrated flake-like morphological changes in the CaO:MgAl2O4 samples. TEM, HRTEM, and SAED studies of a CaO:MgAl2O4 nanocomposite would reveal important details about its morphology, crystallography, and nanostructure. Photocatalytic activity was quantified by studying the degradation of Acid Red-88 (AR-88) dye in a deionized solution, achieving a 70% dye degradation under UV irradiation in 120 min. Plant growth examinations were carried out using dye degraded water to test its suitability for agriculture. The electrochemical energy storage and sensing applications of the prepared nanocomposite were examined using CaO:MgAl2O4 modified carbon paste electrode through cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). In conclusion, the synthesized CaO:MgAl2O4 nanocomposite demonstrated promising morphological and structural characteristics, efficient photocatalytic activity, and potential applications in electrochemical energy storage, highlighting its versatility for various technological and environmental applications. [ABSTRACT FROM AUTHOR]

Square planar complexes of Ni(II) and Pd(II) of a new redox-active pentadentate azo-appended 2-aminophenol ligand (H4L = N,N′-bis(2-hydroxy-3,5-di-tert-butylphenyl)-2,2′-diamino-ortho-azobenzene) in three accessible redox levels [amidophenolate(2−), semiquinonate(1−) π radical, and quinone(0)] were synthesized. The coordinated HL(3−) ligand provides four donor sites [two N(iminophenolates), an N′(azo), and an O(phenolate)], while the phenolic OH group remains free in the three complexes. Cyclic voltammetry on complex [Ni(L)] 1 and its corresponding Pd(II) analogue [Pd(L)] 2 in CH2Cl2 displayed three redox responses (two oxidative at E1/2 = 0.06 V and Epa (anodic peak potential) = 0.80 V and one reductive at −0.77 V for 1 and at E1/2 = 0.08 V and Epa = 0.85 V and at −0.74 V for 2vs. Fc+/Fc). The chemical oxidation of 1 with AgSbF6 afforded [Ni(L)]SbF6·2CH2Cl2 (3·2CH2Cl2). Complex [Pd(L*)] 4, which is coordinated by a phenoxazinyl derivative of L(4−), was obtained via intraligand cyclization in the parent complex 2 under basic oxidizing conditions. The molecular structures of 1, 2, 3·2CH2Cl2 and 4 were elucidated through X-ray crystallography at 100 K. Characterization using 1H NMR, X-band EPR, and UV–VIS–NIR spectroscopy established that the complexes have [NiII{(LISQ)˙2−}] 1, [PdII{(LISQ)˙2−}] 2, [NiII{(LIBQ)−}]SbF6/1+SbF6−(3), and [PdII{(L*AP)˙2−}] 4 electronic states. Complexes 1, 2, and 4 possess paramagnetic St (total spin) = 1/2 ground-state, whereas 3 is diamagnetic (St = 0). Density functional theory (DFT) electronic structural calculations at the B3LYP level rationalized the observed experimental results. Time-dependent (TD)-DFT calculations allowed us to identify the nature of the observed absorption spectra. [ABSTRACT FROM AUTHOR]

The development of electron transport and n‐type materials is still largely dominated by a limited number of organic semiconductors, with fullerenes at the forefront. In contrast, substantial progress has been made in developing hole transport and p‐type materials. Therefore, expanding the range of electron acceptors, making them solution‐processable, and elucidating their structural arrangement by X‐ray crystallography is essential. We synthesised 2,2'‐bi‐(5,6,11,12‐tetraazanaphthacene) (bi‐TANC) and its triptycene end‐capped derivative, 2,2′‐bi(8,13‐dihydro‐8,13‐[1,2]benzenonaphtho‐5,6,15,16‐tetraazanaphthacene) (bi‐TpTANC), as electron acceptors. Bi‐TANC exhibits a herringbone‐like crystal packing with intermolecular π–π overlap, which is observed in typical organic n‐type semiconductors. However, it showed poor solubility, similar to larger acenes. In contrast, bi‐TpTANC exhibited favourable solubility, and its electrochemistry in solution was investigated. In the cyclic voltammogram of bi‐TpTANC, reversible redox waves corresponding to 3‐step/4‐electron transfer were observed at −0.795 V (1e−), −0.927 V (1e−), and −1.44 V (2e−) as half‐wave potentials. The redox wave associated with the two‐electron transfer on the negative low‐potential side indicates the presence of through‐bond charge delocalisation in the monoanionic state. Furthermore, the LUMO level of bi‐TpTANC is −4.1 eV, which indicates its potential as a promising air‐stable n‐type material. [ABSTRACT FROM AUTHOR]

Improving catalytic activity of cathode with noble metal-free catalysts can significantly establish microbial fuel cells (MFCs) as a sustainable and economically affordable technology. This investigation aimed to assess the viability of utilizing tri-metal ferrite (Co0.5Cu0.5 Bi0.1Fe1.9O4) as an oxygen reduction reaction (ORR) catalyst to enhance the performance of cathode in MFCs. Trimetallic ferrite was synthesized using a sol–gel auto-combustion process. Electrochemical evaluations were conducted to assess the efficacy of as-synthesized composite as an ORR catalyst, employing electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). This evaluation revealed that the impregnation of bismuth in the Co–Cu-ferrite structure improves the reduction current response and reduces the charge transfer resistance. Further experiments were conducted to test the performance of this catalyst in an MFC. The MFC with tri-metal ferrite catalyst generated a power density of 11.44 W/m3 with 21.4% coulombic efficiency (CE), which was found to be comparable with commercially available 10% Pt/C used as cathode catalyst in MFC (power density of 12.14 W/m3 and CE of 23.1%) and substantially greater than MFC having bare carbon felt cathode without any catalyst (power density of 2.49 W/m3 and CE of 7.39%). This exceptionally inexpensive ORR catalyst has adequate merit to replace commercial costlier platinum-based cathode catalysts for upscaling MFCs. [ABSTRACT FROM AUTHOR]

Rechargeable Ca batteries offer the advantages of high energy density, low cost, and earth‐abundant constituents, presenting a viable alternative to lithium‐ion batteries. However, using polymer electrolytes in practical Ca batteries is not often reported, despite its potential to prevent leakage and preserve battery flexibility. Herein, a Ca(BH4)2‐based gel‐polymer electrolyte (GPE) is prepared from Ca(BH4)2 and poly(tetrahydrofuran) (pTHF) and tested its performance in Ca batteries. The electrolyte demonstrates excellent stability against Ca‐metal anodes and high ionic conductivity. The results of infrared spectroscopy and 1H and 11B NMR indicate that the terminal ─OH groups of pTHF reacted with BH4− anions to form B─H─(pTHF)3 moieties, achieving cross‐linking and solidification. Cyclic voltammetry measurements indicate the occurrence of reversible Ca plating/stripping. To improve the performance at high current densities, the GPE is supplemented with LiBH4 to achieve a lower overpotential in the Ca plating/stripping process. An all‐solid‐state Ca‐metal battery with a dual‐cation (Ca2+ and Li+) GPE, a Ca‐metal anode, and a Li4Ti5O12 cathode sustained >200 cycles, confirming their feasibility. The results pave the way for further developing lithium salt‐free Ca batteries by developing electrolyte salts with high oxidation stability and optimal electrochemical properties. [ABSTRACT FROM AUTHOR]

Direct hydrazine fuel cells (DHFC) insist on the evolved and persistent electrocatalysts for anodic hydrazine oxidation reaction (HzOR). Herein, PdO promoted CuO heterostructures supported on γ‐Al2O3 are depicted as efficient electrocatalysts for HzOR. γ‐Al2O3 is prepared by precipitation method while metal precursors are incorporated by co‐impregnation technique. Physiochemically characterized PdO‐CuO/Al2O3 mesoporous composites displayed large electrochemical active surface area (ECSA) i. e., 0.18 cm2, high current density (j) i. e., 35.7 mA cm−2, larger diffusion coefficient (D°) i. e., 29.3×10−4 (cm2s−1), large apparent rate constant (kapp) i. e., 13.2 cm−1 with low charge transfer resistance (Rct) i. e., 3.6 kΩ shown by the best catalyst i. e., 1 % PdO‐CuO/Al2O3. Cyclic voltammetry indicated that the fabricated working electrodes offer high efficiency towards HzOR in alkaline medium in such a way that 1 % PdO‐CuO/Al2O3 produced 600 times higher oxidation current than CuO/Al2O3 composite. Owing to stability and reproducibility, PdO modified CuO/Al2O3 would achieve a huge catalytic significance in multiple electrochemical oxidation reactions with economic and ecological benefits. [ABSTRACT FROM AUTHOR]

To meet the increasing demands for food production, the utilization of cost‐effective pesticides like carbofuran (CB) becomes essential. CB poses a significant risk to human health due to its high toxicity. Therefore, accurate quantification of CB residue is essential for environmental safety and human health. Electrochemical sensors have proven to be an outstanding choice for the accurate detection and quantification of carbofuran residues. CB is electrochemically inactive and was first hydrolyzed in an alkaline medium to yield an anodically active phenolic derivative carbofuran phenol (CP). This report details the development of a voltammetric sensor for the accurate detection of CB residues utilizing the cyclic voltammetry technique and the electrochemical reactions of CP at WS2 nanosheet‐modified electrodes in phosphate buffer solution (PBS). The constructed sensor has displayed a linear range of carbofuran detection from 10–90 μM, with a limit of detection (LOD) of 0.38 μM and sensitivity of 0.303 μA μM−1 cm−2. Additionally, the developed sensor has been employed to monitor CB residues in real soil and water samples and it shows a recovery greater than 95 %. The developed sensor enables the cost‐effective monitoring of carbofuran in real samples. [ABSTRACT FROM AUTHOR]

In this paper, the novel ECL sensor of the 6‐methoxychromone (6‐MC)/S2O82− system was designed by using 2‐naphthalene sulfonic acid (2‐NSA) as a co‐reaction accelerator. Fluorescence, ECL spectrum, and cyclic voltammetry (CV) were used to explore extensively the ECL mechanism of the system. It is worth pointing out that 2‐naphthalene sulfonic acid (2‐NSA) was first proposed as a co‐reaction accelerator, reacting with the coreactant K2S2O8 rather than the luminophore, promoting the generation of additional oxidant SO4− from S2O82−, thus amplifying the ECL signal. Furthermore, under the optimal experimental conditions, the high sensitivity of the 2‐naphthalene sulfonic acid (2‐NSA)+6‐methoxychromone (6‐MC)/S2O82− system was realized for the detection of methyl violet (MV) in the linear range of 10−8~10−2 M, with a detection limit of 5.14×10−10 M. In addition, this find offers some guidance for further developing co‐reaction accelerators with excellent performance in the future. [ABSTRACT FROM AUTHOR]

Metal ion-DNA interactions play a crucial role in modulating the structure and function of genetic material in the natural environment. In this study, we report on the favorable electrochemical activity of holmium(III) (Ho3+) on a glassy carbon electrode (GCE) and its interaction with double-stranded DNA. The interaction between DNA and Ho3+ was investigated for the first time using cyclic voltammetry and differential pulse voltammetry. The electrochemical behavior of Ho3+ ions on a GCE exhibited a reversible electron transfer process, indicative of its redox activity. A linear correlation between the peak current and the square root of the scan rate was observed, suggesting a diffusion-controlled kinetic regime for the electrochemical process. Additionally, fluorescence and absorption spectroscopy were employed to confirm the binding of Ho3+ to DNA. Our findings demonstrate that, at pH 7.2, specific DNA bases and phosphate groups can interact with Ho3+ ions. Moreover, electrochemical measurements suggest that Ho3+ ions bind to DNA via a groove binding mode, with a calculated binding ratio of 1:1 between Ho3+ and DNA. Notably, under optimal conditions, an increase in the amount of DNA leads to a significant reduction in the current intensity of Ho3+ ions. [ABSTRACT FROM AUTHOR]

Azobenzenes (ABs) are versatile compounds featured in numerous applications for energy storage systems, such as solar thermal storages or phase change materials. Additionally, the reversible one‐electron reduction of these diazenes to the nitrogen‐based radical anion has been used in battery applications. Although the oxidation of ABs is normally irreversible, 4,4'‐diamino substitution allows a reversible 2e− oxidation, which is attributed to the formation of a stable bis‐quinoidal structure. Herein, we present a system that shows a bipolar redox behaviour. In this way, ABs can serve not only as anolytes, but also as catholytes. The resulting redox potentials can be tailored by suitable amine‐ and ring‐substitution. For the first time, the solid‐state structure of the oxidized form could be characterized by X‐ray diffraction. [ABSTRACT FROM AUTHOR]

The ongoing pursuit of cost-effective approaches for synthesizing transition metal sulfide heterostructure oxygen evolution electrocatalysts, with the objective of optimizing active site exposure and stabilizing spatial framework, remains a significant challenge. In this study, self-supported bimetallic iron-nickel sulfide (Fe 1-x S-NiS/NF) nanosheet heterostructures were successfully fabricated in situ on nickel foam through the direct sulfurization of bimetallic carbonate precursors. The effects of sulfurization temperature and Fe content on the oxygen evolution reaction (OER) performance of the catalyst are investigated, and the best conditions are found to be 350 °C and 2 mmol, respectively. As expected, the optimized catalyst demonstrates remarkable OER performance in an alkaline solution with low overpotentials of 235 mV and 333 mV at high current densities of 50 mA cm−2 and 100 mA cm−2, respectively. Furthermore, the catalyst shows long-term stability lasting for 35 h at 60 mA cm−2 with a negligible shift in the polarization curve observed even after 2000 cyclic voltammetry cycles, while also exhibiting good structural preservation. The current study has the potential to offer valuable insights into the fabrication of electrocatalysts based on metal sulfide heterostructures. A simple hydrothermal-sulfurization strategy was adopted to fabricate series of self-supported iron-nickel sulfide nanosheet heterostructures catalysts with excellent OER performance. [Display omitted] • Self-supported Fe 1-x S-NiS/NF nanosheets were synthesized by sulfurization of carbonates. • Effects of sulfurization temperature and Fe content on the OER performance are investigated. • The Fe 1-x S-NiS/NF-2 catalyst exhibits excellent OER performance. [ABSTRACT FROM AUTHOR]

Bismuth-based semiconductors have attracted significant attention in rechargeable batteries and supercapacitor devices. In this study, layered structured bismuth germanate (Bi12GeO20) was synthesized using hexamine as a surfactant, at 850 °C, and utilized as electro-active material for supercapacitor and sodium ion (NaB) storage applications. The physical characterization of the prepared Bi12GeO20 was studied with various characterization and microscopic analyses such as XRD, FT-IR, FESEM with EDS, HRTEM, and XPS analysis. The XRD analysis exposed the successful formation of a highly crystalline sillenite phase of Bi12GeO20. The surface morphology analysis FE-SEM and HR-TEM revealed the effective construction of the 2D layered structure of Bi12GeO20. The EDS results profound that uniform distribution of the Bi, Ge, and O elements with good elemental stoichiometry. The supercapacitor properties of the prepared Bi12GeO20 were evaluated with the help of three electrode method using cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance (EIS) techniques in the aqueous solution of 3.0 M KOH. The prepared Bi12GeO20 architecture shows a higher specific capacitance of 355 F g−1, with a current density of 1 A g−1. Finally, the sodium-ion storage capacity of Bi12GeO20 was evaluated using a coin cell-type electrode. The as-synthesized Bi12GeO20 material was utilized as an anode for Na ion storage and demonstrated a high specific capacity of 740 mAh g−1 at 0.1 C rate. With these appreciable electrochemical performances, the single component Bi12GeO20 holds an ideal alternative electrode material to develop high-performance power and energy storage devices. [ABSTRACT FROM AUTHOR]

This research examines vanadium‐deficient V2C MXene, a two‐dimensional (2D) vanadium carbide with exceptional electrochemical properties for rechargeable zinc‐ion batteries. Through a meticulous etching process, a V‐deficient, porous architecture with an expansive surface area is achieved, fostering three‐dimensional (3D) diffusion channels and boosting zinc ion storage. Analytical techniques like scanning electron microscopy, transmission electron microscopy, Brunauer–Emmett–Teller, and X‐ray diffraction confirm the formation of V2C MXene and its defective porous structure. X‐ray photoelectron spectroscopy further verifies its transformation from the MAX phase to MXene, noting an increase in V3+ and V4+ states with etching. Cyclic voltammetry reveals superior de‐zincation kinetics, evidenced by consistent V3+/V4+ oxidation peaks at varied scanning rates. Overall, this V‐deficient MXene outperforms raw MXenes in capacity and rate, although its capacity diminishes over extended cycling due to structural flaws. Theoretical analyses suggest conductivity rises with vacancies, enhancing 3D ionic diffusion as vacancy size grows. This work sheds light on enhancing V‐based MXene structures for optimized zinc‐ion storage. [ABSTRACT FROM AUTHOR]

In the present work, we have synthesized sulfone-bridged tetraphenyl porphyrin, 2D polymer 'P' (C44H28N4OySx)n through a one-pot reaction of tetra(p-bromophenyl) porphyrin, S with sulfur powder in DMF. The polymer 'P' has been further reacted with erythrosine B for the fabrication of composite photocatalyst, C (C65H37N4NaOySx)n using donor– acceptor conjugation protocol. Herein, both compounds (P & C) have been well characterized by MAS 13C-NMR, XPS, IR, powder XRD, TGA, SEM-EDX, UV-Vis spectra, and Cyclic Voltammetry. Due to the low HOMO-LUMO band gap energy, the applicability of the composite photocatalyst (C, 2.1 eV) has been studied in terms of oxidation of sulfide to sulfoxide. The present work shows a promising route for the development of sulfone-bridged 2D porphyrin covalent organic framework (COF) and its composite photocatalyst as well as its usage in photocatalytic sulfoxidation reaction. [ABSTRACT FROM AUTHOR]

Nanocomposite SnSeO3/ZnSeO3 has been synthesized by hydrothermal method. X-ray powder diffraction confirms formation of SnSeO3/ZnSeO3 nanocomposite. It exhibits an interesting morphology of needle like nanorod structure. Thermal analysis reveals the thermal stability, decomposition behavior and critical temperatures where significant weight loss occurs. X-ray photoemission explains the role of the chemical state Sn, Zn, Se and O in SnSeO3/ZnSeO3. Electrochemical study has been made in both three electrode and two electrode system. In three electrode system, cyclic voltammetry exhibits a bell-shaped curve and the operational potential window is 0.8 V. The specific capacitance is 78.65 F/g for 5 mV scan rate. Chronopotentiometry shows quasi-triangular curves demonstrating the behavior of pseudo capacitors. Specific capacitances of 72.02 F/g was delivered at 1 A/g current density in 3M electrolyte of KOH. The plot of Nyquist for SnSeO3//ZnSeO3 confirms pseudo capacitor behavior. The series resistance Rs is low that is 0.78 Ω and charge transfer resistance is 0.42 Ω. Symmetric SnSeO3/ZnSeO3 supercapacitor device that is, two electrode system, is fabricated using 3M KOH electrolyte. Operational potential window is 1.5V. Cyclic voltammetry curves of the device show excellent capacitive behavior. The symmetric device produced specific capacitances of 39.37F/g, energy density 6.15 Wh kg-1 and power density 374.99 kW kg-1 at 1Ag-1 current density. The cell displayed 73.18% capacity retention, indicating excellent electrode stability for approximately 5000 cycles at a current density of 1 Ag-1 . Nyquist plot suggests that the system is stable and exhibits capacitive behavior. [ABSTRACT FROM AUTHOR]

[Display omitted] A new approach to stabilization of the reduced state of nitroxides in solution is suggested. Thermodynamic stabilization of the strongly basic aminoxyl anions toward protonation and hydrogen bond formation with the solvent was achieved by intramolecular n → π* interactions. A new stable nitroxide radical bearing ortho -acyl group was synthesized to demonstrate this effect by means of cyclic voltammetry. [ABSTRACT FROM AUTHOR]

This study investigates the environmentally friendly synthesis of ZrO2‐NdO mixed nanomaterial using green reducing and capping agents derived from the plant Amaranthus viridis. X‐ray diffraction (XRD) analysis confirmed the successful synthesis of the mixed nanomaterial, revealing an optical band gap of 2.5 eV. The morphology was characterized by spherical‐shaped particles with an average size ranging from 66 to 77 nm. The synthesized ZrO2‐NdO mixed nanomaterial was evaluated for its potential application as an electrode material in energy devices, specifically for pseudocapacitors and water splitting studies. Electrochemical performance was assessed using cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) techniques. Notably, a specific capacitance of 573.5 F/g was achieved through CV at a scan rate of 2 mV/s. Fabricated electrocatalyst was further analyzed for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), and the results showed better over potential value of 164 mV for HER studies. The stability analysis further endorsed the large‐scale commercialization possibility of ZrO‐NdO‐based electrode material. [ABSTRACT FROM AUTHOR]

Synthesis of 3,8-diaryl-2H-cyclohepta[b]furan-2-ones was accomplished by the one-pot procedure involving sequential iodation and Suzuki–Miyaura coupling reactions. The optical and structural characteristics of 3,8-diaryl-2H-cyclohepta[b]furan-2-ones prepared were scrutinized using UV/Vis spectroscopy, theoretical calculations, and single-crystal X-ray crystallography. The redox properties of the compounds were also evaluated through cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The findings reveal that the introduction of aryl groups at both the 3- and 8-positions significantly influences the electronic properties of the CHFs, resulting in distinct optical and electrochemical characteristics. [ABSTRACT FROM AUTHOR]

Understanding the morphology and electronic properties of poly(fullerene)s is crucial for the development of new organic devices. This work addresses the fabrication and characterization of Langmuir–Schaefer (LS) films of poly(fullerene)s based on C60 with short (HSS8) and long (HSS16) sidechains, solubilized in chloroform or xylene. In addition, density functional theory (DFT) calculations are used to optimize the molecular geometries, determine energies, and investigate the influence of solvent applied. Depending on the organic solvent, floating material isotherms indicate the formation of disordered aggregates in the aqueous subphase. The influence of solvent in LS films is also evidenced by way of atomic force microscopy (AFM), UV‐vis, and cyclic voltammetry (CV) measurements. From DFT calculations, the arms of the poly(fullerene)s start to extend from an initial position of surrounding the fullerene sphere. In AFM measurements, depending on the organic solvent, the roughness significantly reduces, while the homogeneity is much higher. In UV‐vis and CV measurements, the propensity to form aggregates depends mainly on the polarization of the solvent and is directly related to the maximum absorption, oxidation, and reduction peaks. From the optical bandgap energy values, the poly(fullerene)s studied here present high potential for application in organic electronic devices. [ABSTRACT FROM AUTHOR]

This paper reports the synthesis and structural characterization of a novel azide-bridged polymeric manganese (III) Schiff base complex, using 2-((allylimino)methyl)-6-ethoxyphenol as a ligand. The crystal structure of the synthesized compound, elucidated by single-crystal X-ray diffraction analysis, indicates that it crystallizes in the monoclinic space group P21/c. The complex is found to display an octahedral geometry in which the central manganese Mn(III) coordinates with two bidentate donor Schiff base ligands via oxygen and nitrogen atoms. In addition, the metallic centers are linked together to form a one-dimensional chain bridged by end-to-end azide ligands. To offer a more thorough characterization of the synthesized compound, the study incorporates experimental data from FT-IR, UV-Vis, and cyclic voltammetry, alongside computational results from Hirshfeld surface analysis and DFT calculations conducted for both the ligand and complex. The computational analyses provided valuable insights into the intrachain and interchain interactions within the crystal structure, clarified the conformational characteristics of the isolated ligand molecule, and aided in the interpretation of the experimental IR spectra. Furthermore, an assessment of the compound's drug-like properties was conducted using activity spectra for substances (PASS) predictions, revealing potential pharmacological activities. [ABSTRACT FROM AUTHOR]

The complete anodic oxidation of ammonia is an important part of direct ammonia fuel cells. Fabricating a high-performance electrocatalyst for ammonia oxidation reaction is meaningful for developing a direct ammonia fuel cell. Herein, we designed one platinum-decorated NiCo-layered double hydroxide nanoflower on Ni foam (Pt-NiCo-LDH-Ni foam) and measured the electrocatalytic performance via the cyclic voltammetry (CV) technique. The experimental results demonstrated that the optimized Pt-NiCo-LDH-Ni foam showed great electrocatalytic performance, with a low overpotential with a value of −0.573 V, a high current density of 17.75 mA cm−2 for the ammonia oxidation reaction, and good stability. [ABSTRACT FROM AUTHOR]

The influence of the Ni content (1.4 - 9.0 wt. %) in electrodeposited Pd-Ni alloy coatings on the rate of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in an alkaline media was investigated. Electrocatalytic activity of the electrodeposited layers towards methanol oxidation reaction (MOR) was also studied. The composition and surface morphology of the samples were characterized by energy dispersive spectroscopy (EDS) and scanning electron microscopy (SEM). The crystal structure of the Pd-Ni alloys was examined by X-ray diffraction (XRD). Electrochemical experiments were performed by cyclic voltammetry (CV). The presence of concentration ranges with respect to the Ni content is shown, wherein the electrocatalytic activity of the Pd-Ni alloy towards HER, OER and MOR is higher than that of pure Pd. [ABSTRACT FROM AUTHOR]

Using a chemiluminescence reaction between luminol and H2O2 in basic solution, an ultrasensitive electrochemiluminescence (ECL) aptasensor was developed for the determination of tobramycin (TOB), as an aminoglycoside antibiotic. Ti3C2/Ni/Sm-LDH-based nanocomposite effectively catalyzes the oxidation of luminol and decomposition of H2O2, leading to the formation of different reactive oxygen species (ROSs), thus amplifying the ECL signal intensity of luminol, which can be used for the determination of TOB concentration. To evaluate the performance of the electrochemiluminescence aptasensor and synthesized nanocomposite, different methods such as cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) analyses were performed. The considerable specific area, large number of active sites, and enhanced electron transfer reaction on this nanocomposite led to the development of an ECL aptasensor with high sensitivity and electrocatalytic activity. After optimizing the preparation method and analysis conditions, the aptasensor revealed a wide linear response ranging from 1.0 pM to 1.0 μM with a detection limit of 18 pM, displaying outstanding accuracy, specificity, and response stability. The developed ECL sensor was found to be applicable to the determination of TOB in human serum samples and is anticipated to possess excellent clinical potentials for detecting other antibiotics, as well. [ABSTRACT FROM AUTHOR]

Tetrahydroacridines arouse particular interest due to the potential possibilities of application in the medical field and protection against corrosion. Bis-tetrahydroacridines were newly synthesized by Pfitzinger condensation of 5,5′-(ethane-1,2-diyl) diindoline-2,3-dione with several cyclanones. NMR, MS, and FT-IR were used to prove their molecular structure. In addition, a computer-aided study was performed for the lowest energy conformers of each structure, in vacuum conditions, at ground state using DFT models to assess their electronic properties. UV–Vis and voltammetric methods (cyclic voltammetry, differential pulse voltammetry, and rotating disk electrode voltammetry) were used to investigate their optical and electrochemical properties. The results obtained for these π-conjugated heteroaromatic compounds lead to the conclusion that they have real potential in applications in different fields such as pharmaceuticals and especially as corrosion inhibitors. [ABSTRACT FROM AUTHOR]

In this work, we have prepared and characterized some gold compounds wearing a N-heterocyclic carbene (NHC) ligand as well as alkynyl derivatives with different substituents. The study of their electrochemical behavior reveals that these complexes show an irreversible wave at potentials ranging between −2.79 and −2.91 V, referenced to the ferrocenium/ferrocene pair. DFT calculations indicate that the reduction occurs mainly on the aryl−C≡C fragment. The cyclic voltammetry experiments under CO2 atmosphere show an increase in the faradaic current of the reduction wave compared to the experiments under argon atmosphere, indicating a possible catalytic activity towards the carbon dioxide reduction reaction (CO2RR). [ABSTRACT FROM AUTHOR]

High-oxygen-permeability ionomers (HOPIs) are being actively developed to enhance the performance and durability of high-power polymer electrolyte membrane fuel cells (PEMFCs). While methods for evaluating binder performance are well-established, techniques for assessing binder durability and measuring its degradation in situ during the AST process remain limited. This study examines the distribution of relaxation times (DRT) and Warburg-like response (WLR) methods as in situ analysis techniques during the catalyst-accelerated stress test (AST) process. We conducted catalyst-ASTs (0.6–0.95 V cycling) for 20,000 cycles, monitoring changes using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and linear sweep voltammetry (LSV). Contrary to expectations, during the catalyst-AST, the ion transport resistance of the binder decreased, indicating no binder degradation. Scanning electron microscopy/energy dispersive spectrometer (SEM/EDS) analysis revealed that the degradation rate of the catalyst and the support was relatively higher than that of the binder, leading to a reduction in catalyst layer thickness and improved binder network formation. By applying the DRT method during the catalyst-AST process, we were able to measure the increase in oxygen reduction reaction (ORR) resistance and the decrease in proton transport resistance in situ. This allowed for the real-time detection of the reduction in catalyst layer thickness and improvements in ionomer networks due to catalyst and support degradation. These findings provide new insights into the complex interplay between catalyst degradation and binder performance, contributing to the development of more durable PEMFC components. [ABSTRACT FROM AUTHOR]

In this study, a new and simple glassy carbon electrode modified with carbon nanohorns (SWCNH/GCE) was used for the determination of Cr(VI) in aqueous matrices via adsorptive cathodic stripping voltammetry (AdCSV). The modified electrode was characterized via field emission scanning electron microscopy and cyclic voltammetry, which revealed a homogeneous distribution of spherical agglomerates of SWCNH on the electrode surface. The modification increased the electrochemically active area from 0.10 cm2 ± 0.01 (GCE) to 0.16 cm2 ± 0.01 (SWCNH/GCE). The optimized analytical conditions were as follows: a supporting electrolyte (0.15 mol L−1 HCl), an accumulation potential of 0.8 V versus Ag/AgCl, and an accumulation time of 240 s. Validation of the analytical methodology was performed, obtaining a linear range between 20 and 100 µg L−1, a limit of detection of 3.5 µg L−1, and a limit of quantification of 11.6 µg L−1 with good accuracy and precision. The method was applied to the analysis of spiked tap water samples, and the results were compared using a flame atomic absorption spectrophotometer (FAAS) with no significant statistical differences. [ABSTRACT FROM AUTHOR]

This study aimed to develop an electrochemical method for the electrochemical determination of bufexamac (BUF), an important anti-inflammatory drug. For this purpose, the electrochemical properties of BUF were elucidated using a glassy carbon electrode (GCE) and cyclic voltammetry. The electrochemical performance of BUF was examined by the differential pulse voltammetry (DPV) method. It was observed that the response of GCE to DBT was linear in the concentration range of 6.0 × 10-6 M and 1.0 × 10-4 M. The limit of detection (LOD) was found to be 2.64 × 10-8 M; The limit of quantification (LOQ) was calculated as 8.79 × 10-8 M. The dexketoprofen tromethamine (DEX), diclofenac (DIC), and ibuprofen (IBU) were used as model active compounds to illustrate the oxidation mechanism of BUF. A simple, rapid, and sensitive electrochemical method for quantitatively determining BUF in a commercial sample of human serum was developed and validated. The calibration curve was linear in the 8.0 × 10-6 - 1.0 × 10-4 M in the biological media. The LOD for the commercial sample of human serum was set at 1.59 × 10-7 M. The electrochemical response of BUF in the presence of interferent was evaluated. The data obtained from the study showed that the developed method can be used in sensitive and selective BUF determination. [ABSTRACT FROM AUTHOR]

Carbon steel piping and tubing can be degraded by hydrogen uptake. The hydrogen permeation method is commonly applied to testing and qualification steel in response to hydrogen atom diffusion. Cyclic voltammetry (CV) has recently been proposed because it is a more straightforward method than permeation. A comprehensive study was conducted to investigate whether these two methods are comparable. A model alloy of SA 210 grade was studied. The study involved preparing specimens with varying microstructures through different heat treatments. Subsequently, metallographic analysis was conducted on each microstructural variation, followed by mechanical testing to evaluate the changes obtained before and after the hydrogen absorption test. The CV method consisted of three steps: CV before H absorption to search for a reference voltammogram, H charging, and CV after H absorption to determine the after-charge voltammogram. Electrochemical hydrogen permeation tests were performed in a Devanathan–Stachursky double cell. A comparison of the CV and permeation methods revealed that they show pretty similar results in evaluating the interaction between steel and hydrogen. Permeation methods provide quantitative results, while CV offers more qualitative insights. Both methods show that the quenched steel has the slowest hydrogen diffusion rate compared with those in normalized and base material conditions. [ABSTRACT FROM AUTHOR]

Owing to their characteristics like fast charge–discharge rate, very long life, simple geometry and eco-friendly nature, supercapacitor is an emerging technology to fulfil the present and future requirements of the energy. The performance of a supercapacitor is derived from the composition and morphology of the electrode. 2D materials possess various excellent structural properties like surface area, flexibility in the atomic scale dimension and mechanical strength with high electrical conductivity. This makes them an entrusted material to be used as an electrode material. The teaming of 2D materials and layered transition metal dichalcogenides have been of great interest for electrode materials. In this study, the reduction of graphene oxide is done by an environment-friendly synthesis method using cow urine, and then, synthesizing the reduced graphene oxide (rGO) and transition metal dichalcogenides (TMD) composite using the refluxing method. The modified pencil graphite electrode (PGE) was functionalized using the above composite and the performance is comparable to that of glassy carbon electrode. Our main motive was to develop a low-cost, sustainable and highly effective MoS2–rGO/PGE, which is completely based on an environment and eco-friendly method using natural precursors. The prepared MoS2–rGO nanocomposite was characterized by XRD, SEM and EDX, which revealed the formation as well as its morphological scenario. MoS2–rGO/PGE is explored as electrode material by electrochemical characterization with the 3-electrode system through cyclic voltammetry and electrochemical impedance spectroscopy, which exhibit maximum specific capacitance with good cycle stability. [ABSTRACT FROM AUTHOR]

In this study, Cu- and Zn-doped SnO2 nanoparticles (NPs) were synthesized by using the solvothermal method. The synthesized NPs were explored to check their supercapacitor, photovoltaic and magnetic properties. The Cu-doped SnO2 NPs showed a high specific capacitance of 386 F g−1 at 20 mV s−1 in 1 M KOH electrolyte and remarkable catalytic performance as a counter electrode (CE) for dye-sensitized solar cells (DSSCs), achieving a power conversion efficiency (PCE) of 10.70%, comparable to that of Pt CE. Moreover, Cu-doped SnO2 NPs displayed the highest room-temperature ferromagnetism, indicating their potential for magnetic device applications. Our results suggest that doped SnO2 NPs are promising candidates for multifunctional nanomaterials in energy and information technologies. [ABSTRACT FROM AUTHOR]

A series of europium doped lanthanum oxychloride samples were prepared through solid state method which were utilized as an electrode material and also as photocatalyst. The compounds form tetragonal phase having P4/nmm space group (No. 129). The sample's energy band-gap vary in between 4.14 and 4.35 eV. With a carbon paste electrode in a 0.1 M KOH electrolyte, Cyclic Voltammetry (CV) and Electrochemical (AC) Impedance Spectroscopy are performed. Results reveal that the sample synthesized can be an electrode material for sensing tin in alkaline medium in the concentration range of 1 to 5 mM. Also, the samples are considered to be photocatalyst for the decolourization of Rhodamine.B (Rh.B) dye in aqueous medium concentration of 10 ppm using UV light irradiation. LaOCl:Eu3+ sample as catalyst be able to degrade the Rh.B dye to an extent of 90% in 60 mins. These results demonstrated the relevance of synthesized compound for sensor and photocatalytic applications. Novelty: In this article, the La1-xEuxOCl (0.00 ≤ x ≤ 0.09) synthesised compounds were characterized for morphological nature, structural feature, and functional group analysis with band gap energies. Very particularly for the first time the synthesized samples have undergone preliminary research into their possible usage as electrodes for sensor applicability involving the detection of Tin in alkaline media. Moreover, the samples offered improved photocatalytic effectiveness for the decolourization of Rhodamine.B dye under the UV light irradiation. [ABSTRACT FROM AUTHOR]

Additives are very important to enhance the performance of lead-acid batteries. In this paper, formic acid is used as an electrolyte additive to study its effect on battery performance. The results show formic acid has an opposite effect on the electrochemical properties of pure lead at positive and negative potentials. Besides, formic acid can make more active materials participate in the reaction, increase the rate of conversion of lead to lead sulfate, and reduce the internal resistance of the battery. Moreover, formic acid batteries exhibit better rate performance and higher specific discharge capacity than the blank. Especially, when the 0.5 wt% formic acid is used, the discharge capacity can reach 87.0 mAh g−1 when it is discharged at 400 mA g−1. After 1200 cycles of charge and discharge at a current density of 100 mA g−1, the specific discharge capacity is still 68.1 mAh g−1, which is 1.42 times higher than that of blank cells. [ABSTRACT FROM AUTHOR]

To prepare Mg–Al-Nd alloys electrochemically, the electrochemical co-reduction mechanism of Mg(II), Al(III), and Nd(III) was probed in the LiCl-NaCl-MgCl2-AlF3 melts on a molybdenum electrode by means of various electrochemical measurement techniques, i.e., cyclic voltammetry, square wave voltammetry, chronopotentiometry, and open circuit chronopotentiometry. It was found that Nd could deposit on pre-deposited Al metal and form Nd-Al intermetallics in the LiCl-NaCl-NdCl3-MgCl2-AlF3 system, and the electrochemical signal related to the formation of ternary intermetallics was not detected. The co-reduction of Mg(II), Al(III), and Nd(III) was carried out on molybdenum electrode by galvanostatic electrolysis to prepare Mg–Al-Nd alloy, and samples were characterized by X-ray diffraction, scanning electron microscopy (SEM) with energy-dispersive spectrometry (EDS), and inductively coupled plasma-atomic emission spectrometry (ICP-AES). The results indicate that the alloy products were comprised of Al2Nd intermetallic, Mg and Al phases, and the Mg–Al compound was not observed in the alloys. [ABSTRACT FROM AUTHOR]

NaAlCl4 solid electrolyte is a highly promising solid-state sodium-ion electrolyte with significant application potential. However, most studies on the modification of such material have focused on the impact of cation doping on performance, and the effects of anion doping remain unknown. In this work, fluoride (F−) and borohydride (BH4−) were successfully introduced into NaAlCl4 using a mechanical ball milling method, resulting in the synthesis of NaAlCl4−xFx (x = 0, 0.1, 0.3, 0.5, and 0.7) and NaAlCl4−x(BH4)x (x = 0.1 and 0.3). These derivatives maintain the same orthorhombic structure as NaAlCl4. Electrochemical measurements validate the feasibility of F− and BH4− doping for modifying the NaAlCl4 electrolyte. X-ray photoelectron spectroscopy (XPS) analyses demonstrate that the fluorinated Na/NaAlCl3.5F0.5 interphase formed during cyclic voltammetry (CV) measurements, this prevented further side reactions. This work reveals that F− and BH4− doping exhibit similar electrochemical effects, holds profound practical significance for future research in modifying halide-based sodium ion solid electrolytes. [ABSTRACT FROM AUTHOR]

In this work, efficient and environmentally friendly electrocatalysts based on 2D nanocrystals of graphitic carbon nitride (g-C3N4) decorated with praseodymium orthoferrite (PrFeO3) nanoparticles were designed and synthesized for the efficient electrocatalytic treatment of pharmaceutical wastewater. Nanocrystalline g-C3N4 was obtained through the thermal polymerization of urea in air. Self-propagating high-temperature synthesis (SHS) was employed for producing PrFeO3. Subsequently, the nanopowders underwent ethanol-assisted mechanochemical treatment using a planetary ball mill. As a result, a series of samples was obtained with the PrFeO3 content ranging from 0 to 100 wt%. The resulting nanocomposites were dispersed in a solution of isopropyl alcohol with the addition of 0.5% Nafion; thereafter, the suspensions were applied to an ITO glass substrate to form electroactive thin films. The series underwent analysis using an X-ray diffraction, scanning electron microscopy, surface area and porosity analysis, cyclic voltammetry, and electrochemical impedance spectroscopy. The influence of the g-C3N4 to PrFeO3 ratio on the electrochemical activity during the decomposition of tetracycline hydrochloride was analyzed. Consequently, an optimal ratio was determined, leading to the rapid and complete decomposition of the antibiotic in a neutral aqueous environment. In conclusion, it should be noted that the process of electrocatalytic decomposition of tetracycline hydrochloride has been comprehensively studied. [ABSTRACT FROM AUTHOR]

A series of high-capacity chromium oxides (CrOx, x ≥ 2.5) were synthesized as cathode for lithium-ion batteries (LIBs) by a step calcination method at about 300 °C. The results of cyclic voltammetry (CV) test and impedance analysis indicated that there is a certain relationship between the structure compositions and electrochemical performance. The initial phase transitioned into two subsequent phases during the circulation process and the higher the ratio of tetrahedrons [CrO4] to octahedrons [CrO6], the smaller the potential difference between the two phases. The high ratio of Cr8O21 was examined as a case study, the structural evolution during the charge/discharge process was investigated utilizing ex-situ X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscope (TEM), showing a sequential phase transition to nanoparticles of LiCrO2, which exhibit a close-to-amorphous structure, and an irreversible crystalline phase of LiCrO2 that does not contribute to any capacity. The capacity fading is believed due to the unique phase transition behaviors during Li+ insertion/extraction. It is worth noting that Cr8O21 exhibited a high discharge capacity of 320 mAh g−1 (10 mA g−1) with an impressive capacity retention of 88% after 40 cycles. The present study offers valuable insights into comprehending the capacity fading mechanism of a range of chromium oxides, potentially serving as a means to investigate the structural evolution in metal oxides comprising diverse valence states. A series of high-capacity chromium oxides (CrOx, x ≥ 2.5) were synthesized as cathode for lithium-ion batteries (LIBs) by a step calcination method at about 300 °C. This series of compounds was found to switch into [CrO4] and [CrO6] during the cell cycle. As a case study of Cr8O21 with high ratio, ex-situ X-ray diffraction, X-ray photoelectron spectroscopy, and transmission electron microscope show that the phases after transition are the nanoparticles LiCrO2 close to amorphous and the irreversible phase crystal LiCrO2 without providing any capacity, which is the main cause of the drastic capacity fading in the previous circulation. [ABSTRACT FROM AUTHOR]

Water-soluble binders—locust bean gum (LBG) and carboxymethyl cellulose (CMC) were tested with the SnS anode modified by new conducting material polypyrrole—carbon black composite (PPyCB) and compared with the environmentally unfriendly widely used polyvinylidene fluoride (PVdF) as an organic binder. The electrochemical properties of tested electrodes were investigated by galvanostatic charging/discharging tests, cyclic voltammetry, and electrochemical impedance spectroscopy. Kinetic parameters of electrode processes were calculated from resistances. The first discharge capacities were 2150 mAh g−1, 1250 mAh g−1, and 960 mAh g−1 for SnS-PPyCB-LBG, SNS-PPyCB-CMC, and SnS-PPyCCB-PVdF, respectively. The exchange current density for the SnS-PPyCB electrode is in the range of 4.6 × 10−6 mA cm−2 for the system with carboxymethyl cellulose to 1.97 × 10−6 mA cm−2 in the cell with LBG. Compared to PVdF, locust bean gum is an equally effective binder and may even enhance electrode kinetics. [ABSTRACT FROM AUTHOR]

In an effort to better probe the structure–function relationship on the biological [Fe4S4] cluster of [FeFe]‐hydrogenases, a new library of tertiary phosphine‐supported diiron dithiolate complexes [Fe2(μ‐adtNR)(CO)5{P(C6H4X)3}] (1–3) with various substituents (X = F vs. H vs. Me), wherein adtNR is denoted as abbreviation for the (SCH2)2N(C6H4C2H4OC(O)CH2C6H4Me) unit, is prepared as the active site mimics of [FeFe]‐hydrogenases. Notably, the substituent influences of tertiary phosphines on the structures and electrochemical behaviors of 1–3 are studied by spectroscopic and crystallographic techniques as well as cyclic voltammetry. For example, the electronic effect of tertiary phosphines [P(C6H4X)3] is responsible for the electron density around diiron center and the key Fe–Fe as well as Fe–P lengths in 1–3 as revealed by IR spectroscopy and crystallographic analysis. Further, complexes 1–3 show the electrochemical activity for proton reduction into molecular hydrogen (H2) using acetic acid (AcOH) as a proton source. Noticeably, F‐substituent‐containing diiron model complex 1 exhibits greater turnover frequency (i.e., turnover frequency value) and similar overpotential for electrocatalytic H2 evolution relative to H‐ or Me‐substituent‐bearing diiron homologs 2 or 3. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This work is focused on the visualization of latent fingerprints left on unfired brass cartridges. Polymer films were prepared from 2 mM neutral red or 5 mM toluidine blue using two different electrochemical methods (cyclic voltammetry or chronoamperometry) with relatively short polymerization times. The conditions for the deposition of conductive polymers, poly(neutral red) and poly(toluidine blue), from a neutral medium (phosphate buffer with 0.1 M KNO3 or 0.1 M KNO3, respectively) were optimized to produce high-quality visualization of the remaining fingerprints on the brass substrates. The surface morphology and quality of the polymer films after the electrochemical deposition of both polyphenazine dyes were characterized by stereomicroscope. Phenazine dyes, which were used for the visualization of fingerprints, have been shown to provide different degrees of homogeneity in the deposited film. Furthermore, the dependence of the stability of the monomer solutions on their age, use, and storage conditions are discussed. Finally, a methodology is proposed for how to apply this technique of visualizing latent fingerprints with observed details of papillary lines in forensic practice. [ABSTRACT FROM AUTHOR]

The novel mixed-ligand complexes derived from the parent antidepressant phenothiazine drug triflupromazine (TFP) were synthesized along with the secondary ligands glycine and histidine. [Cu(TFP)(Gly)Cl]·2H2O (1) and [Cu(TFP)(His)Cl]·2H2O (2) were examined for their in vitro biological properties. Cyclic voltammetry was used to study the binding of both complexes to CT-DNA. The two complexes were examined for antiviral, antiparasite, and anti-inflammatory applications. An in vitro cytotoxicity study on two different cancer cell lines, MCF-7, HepG2, and a normal cell line, HSF, shows promising selective cytotoxicity for cancer cells. An investigation of the cell cycle and apoptosis rates was evaluated by flow cytometry with Annexin V-FITC/Propidium Iodide (PI) staining of the treated cells. Gene expression and western blotting were carried out to determine the expression levels of the pro-apoptotic markers and the anti-apoptotic marker Bcl2. The tested complexes decreased cell viability and triggered apoptosis in human tumor cell lines. Molecular docking was also used to simulate Bcl2 inhibition. Finally, complex (2) has potent antitumor effects on human tumor cells, especially against HepG2 cells, as seen in the cellular drug uptake assay. Consequently, complex (2) may prove useful against cancer, especially liver cancer. For further understanding, it needs to be explored in vivo. [ABSTRACT FROM AUTHOR]

Mesoporous thin films modified with nanoparticles of metal (Au) have been used for the fabrication of an ultra‐microelectrode array (UMEA). For the first time, UMEAs were studied using probe beam deflection (PBD) and cyclic voltammetry. The study was carried out using the [Fe(CN)6]3−/[Fe(CN)6]4− couple as a redox probe. The electrochemical response is that of an array of nanoelectrodes. The effects of scan rate on the current and PBD signal profiles are discussed in the context of mass transport within the pores and at the solution‐electrode interface. The study suggests that the combination of PBD and CV allows a better understanding of the mass transport phenomena in this type of UMEAs of complex architecture. [ABSTRACT FROM AUTHOR]

Gold electrode modification with nafion and WO3 has been done for oxalate ion detection. The voltammogram of oxalate ion on the surface gold with and without modification showed a significant difference. This means that the modified gold electrode is sensitive to oxalate ions. The performance of the modified electrode in different pH (5, 7, and 12) in the KCl solution also has been studied using cyclic voltammetry. The range of the measurement is from – 1.0 to + 1.0 at a scan rate of 100 mV s -1. The result showed that the optimum measurement pH is 12 with an anodic peak at 0.143 V and no reduction peak. The measurements of 0, 50, 100, 150, 200, and 250 mg L-1 oxalic ion also have been conducted, showing a linear increase in current. The equation obtained is y = 0.5426 x + 0.9127. In addition, the modified gold electrode showed good selectivity towards oxalate detection, as cyclic voltammetry measurements of some interference components did not produce redox peaks in the oxalate oxidation potential range. These findings indicate that gold electrodes modified with Nafion/WO3 significantly affect the potential development of electrochemical oxalate sensors. [ABSTRACT FROM AUTHOR]