Journal of Solid State Electrochemistry最新文献

This work describes the implementation of a low-cost, robust, and sensitive sensor for the efficiency and rapid electrochemical detection of traces of methylene blue (MB) in contaminated aqueous media. An organohydroxyapatite (OHAP) hybrid material was prepared by cross-linking grafting β-cyclodextrin (β-CD) with citric acid (CA) at the surface of an impregnated natural hydroxyapatite (HAPI). The structural characterization of HAPI and OHAP materials was performed using SEM–EDX. Thin films of different materials were deposited on the surface of a glassy carbon electrode (GCE); their surface charge and permeability were evaluated by multisweep cyclic voltammetry using [Fe(CN)₆]^3−/4− and [Ru(NH₃)₆]^3+/2+ as redox probe systems. The electrochemical behavior of MB on the GCE modified by a film of HAPI or OHAP was also studied by cyclic voltammetry. As with [Ru(NH₃)₆]³⁺ ions, the cyclic voltammograms obtained showed that MB molecules are quantitatively and progressively accumulated on OHAP thin film. Then, the GCE/OHAP electrode was exploited to build a sensitive sensor for the detection of MB. In comparison with the bare GCE, the GCE/OHAP exhibited more sensitive electrochemical response toward MB. Under optimized conditions, a calibration curve was obtained in the large concentration range from 5.0 × 10^–8 to 400.0 × 10^–8 mol L⁻¹, leading to a limit of detection of 2.15 × 10^–9 mol L⁻¹ (S/N = 3). The developed sensor GCE/OHAP was successfully applied to the electroanalytical sensitive quantification of MB in environmental water samples, such as spring water, river water, and well water.

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Aqueous sodium-ion batteries (ASIBs) are promising for large-scale energy storage due to their cycling stability, safety, and environmental friendliness. However, ​structural instability of cathode materials limits cycle life, while the narrow electrochemical window constrains energy density. In this work, tunnel-type Cu-doped Na_0.44MnO₂ was synthesized via a high-temperature solid-state method. Cu doping suppresses Jahn–Teller (J-T) distortion by reducing the formation of J-T active Mn³⁺ and strengthening Mn–O bonds, ​thereby enhancing structural stability and extending cycle life​. Simultaneously, Cu doping expands Na⁺ diffusion channels, mitigating irreversible strain and suppressing voltage decay​ during cycling. Na_0.44Mn_0.95Cu_0.05O₂ exhibits ​outstanding long-term cycling stability (99.5–100% capacity retention after 2000 cycles at 5 C) and ​superior rate capability. The Na⁺ diffusion coefficient reaches 7.04 × 10⁻¹² cm² s⁻¹, nearly an order of magnitude higher than that of undoped Na_0.44MnO₂ (8.89 × 10⁻¹³ cm² s⁻¹). The mechanisms of Cu doping in stabilizing lattice dynamics and ion transport are systematically discussed.

Zn-Sn alloy coatings are attractive for protecting mild steel due to the barrier effect of Sn and the sacrificial nature of Zn. This study explores the use of sodium citrate as a complexing agent to enhance the performance of Zn-Sn electrodeposited coatings. Coatings were deposited on mild steel using electrolytes with varying citrate concentrations (bath 1 to 4), and analyzed using cyclic voltammetry (CV), scanning electron microscopy (SEM), Tafel polarization and electrochemical impedance spectroscopy (EIS). The results show that 0.1 M citrate significantly improved the surface morphology, leading to more uniform coatings with fewer visible defects. Electrochemical tests revealed a 70% decrease in corrosion current density, and EIS confirmed enhanced barrier properties, which may be attributed to the presence of oxide phases formed on the coating surface. These findings highlight the effectiveness of citrate in producing corrosion-resistant Zn-Sn coatings suitable for chloride-rich environments.

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To combat antibiotic resistance and ensure food quality, the detection of tetracycline (TC) is essential. This study describes the fabrication of a TC sensor using an electrochemical approach based on a 3D (NiS and SiO₂) composite combined with 2D graphene. Furthermore, the synthesized materials were coated onto a nickel foam electrode, which exhibits excellent conductivity, large surface area, and mechanical strength, thereby enhancing electrochemical performance. Additionally, this non enzymatic sensor is cost effective and capable of rapid and low concentration (0.05 µM) detection of tetracycline (TC). The semiconductor and porous structure based active materials demonstrate strong affinity with the functional groups of the target material. This synthesized nanocomposite material was analyzed using various experimental techniques including X-ray diffraction (XRD), Raman spectroscopy, XPS, DRS, Photocurrent, SEM, TEM, Cyclic voltammetry (CV), and Tafel plots. We have developed an electrochemical sensor with a minimum detection Limit of 0.0761 μM, which offers excellent reproducibility, stability, reliability, and remarkable prospects for application in detecting TC in phosphate buffer saline (PBS).

The inflation of breast cancer has been edging to increased cancer-associated morbidity and fatality over the years. The casualty of the detection of biomarkers often deters the proper treatment of the disease. This work discusses the facile alloy/dealloying process for electrochemical detection of the breast cancer biomarker, phenylalanine (Phe). The co-deposition of silver-gold (Ag-Au) alloy at a constant potential on the electrochemically deposited sulfur-doped carbon nanotubes (S-CNT//GCE), forming AgAu/S-CNT//GCE, is consecutively dealloyed to form a highly selective sensor, D-AgAu/S-CNT//GCE. The dealloying strategy of the designed sensor enhances the metallic active sites, causing rapid adsorption of Phe and a significantly higher effective area as compared to other modified electrodes. The steady-state oxidative signal of Phe at + 1.1 V (vs Ag/AgCl) by i-t amperometry demonstrates two linear dependences in the concentration ranges, (5–1000) µM and (1000–2750) µM, exhibiting the limits of detection (LoD) as 0.5 µM and 1.7 µM at S/N = 3, respectively. Besides, the high selectivity of D-AgAu/S-CNT//GCE towards Phe disables the detection of other notable interferants, convincing the anti-interfering ability of the sensor. Certainly, the proposed sensor is subjected to the human serum sample for Phe determination, acquiring suitable recovery values. Overall, the high electrocatalytic properties establish the modified sensor to be dynamic and stable for further applications.

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This study presents a CuO/NiO/MWCNT-modified electrode that exhibits supercapacitor behaviour and simultaneous neurotransmitter sensing, enabling its potential use in self-powered biosensors. The composite was synthesised via a co-precipitation method, and its structural and chemical composition was confirmed using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), UV-Vis spectroscopy, and scanning electron microscopy (SEM), demonstrating successful functionalisation and enhanced surface area. The electrochemical response of the modified glassy carbon electrode (MWCNT/CuO/NiO/MGCE) was evaluated using cyclic voltammetry (CV) and differential pulse voltammetry (DPV), revealing highly selective and sensitive detection of dopamine (DA) and serotonin (5-HT) with detection limits of 0.87 µM (DA) and 0.65 µM (5-HT). The well-separated oxidation peaks with a peak-to-peak separation of 131 mV confirmed interference-free simultaneous quantification. Additionally, the electrode exhibited a specific capacitance of 48.3 F/g at 10 mV/s, indicating stable charge storage performance. These findings establish the CuO/NiO/MWCNT-modified electrode as a strong candidate for integrated self-powered biosensors, where the synergy between charge storage and biosensing functionalities can enable real-time, autonomous neurotransmitter monitoring.

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In supercapacitor (SC) technology, advanced electrode materials are key to improving energy storage. Nickel compounds have been promising electrode materials for SC applications. Herein, the incorporation of zinc as a dopant/composite component with nickel has been investigated to enhance electrochemical properties of the nickel-based SC electrodes. In this study, Ni/Zn layered hydroxide (NZLH) electrodes were synthesized via microwave-assisted hydrothermal method with varying zinc ratios, alongside a pure nickel hydroxide reference. The incorporation of zinc has altered the electrochemical properties of NZLH electrodes without forming a distinct zinc hydroxide phase. NZ10 (with 10% Zn/Ni in the initial synthesis solution) has demonstrated the highest specific capacity with a value of 272.78 mAh/g at 5 A/g current density. The asymmetric SC device achieves a maximum specific capacity of 40.76 mAh/g at a current density of 0.1 A/g using activated carbon (anode) and NZ10 (cathode) materials. After 1000 cycles, the device exhibits excellent capacity retention and coulombic efficiency, recorded at 80.7% and 92.7%, respectively. The notable energy and power densities of 45.5 Wh/kg and 6400 W/kg at 2 A/g current density were measured for the asymmetric SC device in two-electrode system, indicating that the NZLH electrode may serve as a viable choice for energy storage applications.

To enhance the corrosion resistance of 316L stainless steel, which is a potential alternative bipolar plate material for PEMWE or PEMFC, Ni–P amorphous coating was prepared by DC electrodeposition method. The results indicated that the coating’s structure strongly related to the phosphorus (P) content. Under specific phosphorus content conditions, a dense coating (Ni–P-30) with typical amorphous characteristics can be obtained, with a uniform surface morphology and no obvious structural defects. In simulated PEMWE environment, Ni–P-30’s corrosion current density decreased by one order of magnitude and the corrosion potential shifted positively by 0.29 V comparing with untreated steel. The excellent corrosion resistance of the amorphous Ni–P coating is attributed by its continuous and dense microstructure, functioning as an effective physical barrier. Meanwhile, during corrosion process, the P will enrich on the surface from the preferential dissolution of nickel in amorphous Ni–P coatings, improving the corrosion potential, reducing the corrosion current and inhibiting the hydration of Ni. Preliminary studies have shown that Ni–P-coated 316L stainless steel can be used as a replacement for graphite as a bipolar plate for PEMWE and PEMFC.

This study presents a systematic investigation combining density functional theory calculations and machine learning approaches to elucidate sodium adsorption behavior on Nb₂C, NbC, SiC monolayers and their heterostructures (Nb₂C/SiC and NbC/SiC). The research establishes fundamental correlations between charge transfer, adsorption distance, and concentration-dependent stability, while developing a clustered linear regression (CLR) model incorporating material/adsorption-site-dependent electronic dipole moment descriptors for physically interpretable adsorption energy prediction. The electrochemical performance evaluation reveals exceptional properties for both heterostructures: ultralow diffusion barriers (0.234 eV for Nb₂C/SiC and 0.156 eV for NbC/SiC), high theoretical capacities (450.63 and 369.69 mAh/g respectively), and safe operating voltage windows (0.62–0.73 V). These characteristics demonstrate an optimal balance between fast ionic transport and high sodium storage capability, positioning these heterostructures as promising anode candidates for sodium-ion batteries.