Journal of Solid State Electrochemistry最新文献

The massive use of lithium-ion batteries has made their recycling a significant challenge in the new era. In this study, we propose an environmentally friendly electrochemical method for the direct recovery of degraded LiCoO₂ (LCO) cathode materials from spent lithium-ion batteries (LIBs), utilizing deep eutectic solvent-based electrolyte. Spent lithium-ion batteries are first pretreated by discharge, manual disassembly, and calcination to obtain degraded LCO. Electrochemical relithiation is then performed by applying a constant current density to the deep eutectic solvent-based electrolyte, which induces the insertion of Li⁺ into the defect sites of the degraded LCO. After annealing at 700 °C for 2 h, surface impurities are removed, the crystal structure is restored, and regenerated LCO is obtained. Integrated characterization techniques such as ICP, XRD, SEM, XPS and cycling test confirmed the recovery of the Li/Co molar ratio (from 0.61:1 to 0.90:1), the recovery of lattice parameters (c-lattice constant from 14.185 Å to 14.081 Å), and the increase of battery capacity (from 130.3 mAh/g to 140.0 mAh/g). This electrochemical method provides a low-energy, short-process, and high-efficiency alternative to traditional indirect recycling technologies (physical separation, pyrometallurgy, and hydrometallurgy), offering not only a solution to resource sustainability but also a more environmentally friendly strategy for lithium battery recycling technology.

Conducting polymer (CP)-based electrochemical biosensors for SARS-CoV-2 detection, developed by directly immobilizing bioreceptors onto the electrode surface, to optimize key properties such as sensitivity and operational lifespan, have been of interest. Herein, a polyaniline (PANI)-based aptasensor was fabricated for detecting SARS-CoV-2 spike glycoprotein in wastewater. Prior to the application of the aptasensor, the synthesis of PANI was confirmed using techniques such as Fourier Transform Infrared Spectroscopy (FTIR), Ultraviolet-Visible Spectroscopy (UV-Vis), Small Angle X-ray Scattering (SAXS), Malvern Zeta sizer and X-ray Diffraction (XRD), whereby the conductive emeraldine salt of PANI was obtained. Additionally, RAMAN spectroscopy proved the attachment of PANI at the surface of GCE. The fabricated aptasensor demonstrated an exceptional performance, enabling real-time detection of ultra-low concentrations of SARS-CoV-2 spike glycoprotein, within a linear concentration range of 0–0.95 fM, with a sensitivity of 1.69 × 10^− 4 µAfM^− 1 and an LOD of 0.05 fM obtained using SWV. Consequently, the aptasensor showed feasibility in detecting SARS-CoV-2 in real spiked wastewater samples. These results highlight a remarkable sensitivity of the electrochemical aptasensor, positioning it as a powerful and reliable tool for ultrasensitive biosensing applications.

Metal-organic frameworks (MOFs) are transformative materials for electrochemical sensing due to their high surface area, tunable porosity, and structural versatility. This review analyzes progress in MOF-based sensors, highlighting green mechanochemical synthesis as a scalable, solvent-free approach that outperforms traditional methods in efficiency and sustainability. We explore the detection of environmental contaminants (heavy metals, pharmaceuticals, biomarkers) and introduce multifunctional MOF hybrids that enable AI-assisted multi-analyte quantification in complex matrices. Critical strategies to overcome conductivity/stability limitations include hierarchical nanostructuring, 2D nanosheets, bimetallic frameworks, and novel MOF-COF heterostructures. Pioneering wearable/IoT-integrated platforms are presented for real-time monitoring. Despite these advances, challenges persist in scalability, real-world stability, and mechanistic understanding. We propose an industry roadmap featuring 3D-printed MOF electrodes and AI-driven design pipelines to bridge lab innovations with global sustainability challenges, positioning MOF electrochemical sensors as key tools for environmental and health monitoring.

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Cation-disordered rocksalt (DRX) oxides have emerged as attractive candidates for high-capacity lithium-ion battery cathodes, owing to their flexible compositional tunability and potential to access both cationic and anionic redox. However, practical application is hindered by oxygen redox instability and sluggish Li⁺ transport, especially in highly lithium-excess systems. In this study, we investigate fluorine-substituted Mn-based DRX cathode with low lithium excess (Li_1.1Mn_0.7+xTi_0.2−xO_2− xF_x), designed to reconcile the trade-off between Li⁺ diffusion and structural stability. Systematic structural and electrochemical analyses reveal that fluorine doping suppresses oxygen redox activity by boosting the redox capacity contribution by increasing the Mn content. Most notably, fluorine substitution promotes phase transformation from disordered rocksalt to spinel-like domains during cycling via enhanced Mn migration, which in turn significantly enhances Li⁺ transport kinetics. The optimized Li_1.1Mn_0.8Ti_0.1O_1.9F_0.1 cathode delivers a maximum discharge capacity of 228.7 mAh g⁻¹ at 0.1 C and retains 115.4 mAh g⁻¹ at 2 C, outperforming its undoped counterpart (Li_1.1Mn_0.7Ti_0.2O₂: 203.2 mAh g⁻¹ at 0.1 C; 81.0 mAh g⁻¹ at 2 C). These findings provide the dual role of fluorination in structural tuning and redox modulation, offering a new strategy to optimize low lithium-excess DRX systems through controlled fluorination and phase engineering.

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Effective serum of uric acid (UA) identification aids global health surveillance because it is a critical measure of general wellness. Hence, in this paper, we report poly-(tris-(1,10-phenanthrolinenickel (II)) complex (poly (Ni(phen)₃) to detect uric acid (UA). The tris – [1,10-phenanthrolinenickel (II)] (Ni(phen)₃) complex was prepared utilizing a microwave technique, and followed by different analytical techniques were used to confirm the complexformation. Ni(phen)₃ was electrochemically polymerized in the electrochemical investigation on the (GCE) surface and employed as the working electrode for UA sensor. The Ni(phen)₃/GCE of the anodic peak potential and bare GCE are noticed at + 0.53 V and + 0.63 V accordingly. The anodic signal appears on the Ni(phen)₃/GCE at minimal potential with a large peak current. The electrochemical outcomes of UA revealed remarkable sensibility of linear range from. 8 × 10^–9 M to 1.4 × 10^–7 M, with a limit of sensor at 0.042 µM. It explains that the electrochemical detection activity of Ni(phen)₃/GCE is greater than pure GCE. To test the recently developed UA sensor for potential chemical interference using a range of biomolecules, it showed remarkable selectivity in UA identification. Additionally, the Ni(phen)₃/GCE detector demonstrated outstanding performance in UA content detection in a human urinary sample. The Ni(phen)₃/GCE detector has also shown outstanding repeatability, reproducibility, and stability in UA estimation. It is expected that this Ni(phen)₃/GCE would prove to be a successful path towards creating a reliable UA detector.

The electrochemical performance of lab-scale coin-cell batteries is highly sensitive to assembly parameters, which can lead to significant performance variation and hinder the reproducible screening of novel materials. This study presents the application of Design of Experiments (DoE) methodologies to optimize key assembly parameters in coin-cell lithium-ion batteries employing LiMn₂O₄ cathodes. Specifically, the influence of three assembly variables—crimping pressure (700, 800, and 900 kg), number of current collectors (one or two units), and electrolyte volume (30, 50, and 70 µl)—was evaluated in terms of their impact on electrochemical impedance and galvanostatic discharge capacity. Analysis of variance (ANOVA) revealed that crimping pressure had the most significant effect on both response variables. Taguchi optimization identified the optimal assembly configuration as a crimping pressure of 800 kg, an electrolyte volume of 70 µl, and the use of a single current collector. Under these conditions, the battery exhibited the lowest resistance values ((:{R}_{ct}=590:{Omega:})) and the highest discharge capacity (65 mAh g⁻¹). These findings highlight the critical interplay between battery assembly conditions and the functional performance of LiMn₂O₄-based lithium-ion batteries.

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We report a simple voltammetric method using a boron-doped diamond electrode (BDDE) cathodically pretreated (CPT) to detect 2,4-dichlorophenoxyacetic acid (2,4-D) in river water samples from the Amazon region. The voltammetric response was evaluated as a function of anodic pretreatment (APT) and CPT for BDDE using the [Fe(CN)₆]^4‒/3‒ probe and 2,4-D. Electrochemical impedance spectroscopy (EIS) and potential scan rate results demonstrated that CPT enhances the voltammetric responses, particularly for 2,4-D, with a 220% increase in the electroactive area compared to the probe, attributed to interactions between the functional groups of 2,4-D and the electrode surface. Catalytic constant (k_cat) and faradaic capacitance (C_s) were determined for the first time for 2,4-D using CPT-BDDE. Furthermore, diffusion coefficient (D_app) and apparent heterogeneous electron transfer rate constant (k_app) were determined, and a possible mechanism for the oxidation of 2,4-D on the CPT-BDDE surface is proposed. CPT-BDDE exhibited good sensitivity, with a linear dynamic range of 0.1 to 260 µM, and a limit of detection of 20 nM. Furthermore, the sensor demonstrated good selectivity for detecting 2,4-D in the presence of interferents and exhibited good repeatability, reproducibility, and stability. The CPT-BDDE was successfully used to determine 2,4-D in river water samples, showing good recoveries and reliable results by the standard addition method. Finally, the proposed analytical method was evaluated using the Blue Applicability Grade Index (BAGI) and Click Analytical Chemistry Index (CACI) tools. The scores for BAGI and CACI were 80 and 73, respectively. These values reflect good robustness and feasibility of the proposed method.

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Natural biomass-derived carbon materials have emerged as a promising candidate for electrode materials in electrochemical energy storage devices due to their unique advantages, including renewable feedstock, tunable porous structures, and high specific surface area. The application and development of biomass-derived carbons as electrode materials not only enable efficient utilization of waste resources but also effectively reduce the overall costs of energy storage systems, demonstrating significant economic and environmental benefits. In the future, biomass-derived carbon is expected to emerge as one of the promising high-performance, low-cost candidate electrode materials. This review systematically summarizes the classification and sources of biomass precursors, along with their preparation methods and comparative advantages/disadvantages. Then, it shows the recent research progresses on biomass-derived carbon materials and their composites for supercapacitor, Li-ion batteries, Li-S batteries, and metal-air batteries. Furthermore, based on the existing key scientific challenges and technical bottlenecks, this review discusses the critical issues facing biomass-derived carbon materials in energy storage applications and proposes future research directions from the perspectives of material design, process optimization, and mechanistic studies.

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In this study, a new all-solid-state type polyvinylchloride membrane potentiometric microsensor was developed for the determination of fluoxetine in pharmaceutical drugs. The synthesis of the ionophore involved the use of methacrylic acid as a functional monomer, ethylene glycol dimethacrylate as a crosslinker, and fluoxetine as a template, resulting in a fluoxetine-imprinted polymer. The prepared polymer was used as an ionophore in the membrane structure of the microsensor to obtain a selective response against fluoxetine molecules. Subsequently, the fluoxetine-selective microsensor's potentiometric performance characteristics were investigated in detail. The microsensor exhibited a super-Nernstian response with a slope of 60.4 ± 0.7 mV per decade (R²: 0.9990) in fluoxetine solutions over the concentration range of 10^–6 − 10^–2 mol.L⁻¹. The microsensor also exhibited an optimum performance in the pH range of 4.0–7.0. The response time of the developed microsensor was determined to be ≤ 15 s, and the microsensor could be used for six weeks without significant potential divergence. The developed microsensor has been successfully used for fluoxetine determination in pharmaceutical drug samples. The potentiometric results were statistically compared with the UV–Vis spectroscopic results. The obtained results were in good harmony at a confidence level of 95%.

Three different types of Co₃O₄-based anode materials with different binders: polyvinylidene fluoride (PVDF), polyacrylic acid with carboxymethyl cellulose (PAA/CMC) and poly(3,4-ethylenedioxythiophene): polystyrene sulfonate with CMC (PEDOT: PSS/CMC) were investigated. It was demonstrated previously that the use of the conductive binder PEDOT: PSS/CMC significantly increased the electrochemical performance of the anode materials even at a current density of 1 C (890 mA∙g⁻¹). The cycling stability was also much higher in comparison with that of the two other electrodes. These effects can be explained by the presence of the conducting polymer PEDOT: PSS as a binder component. To confirm this, impedance spectra of all three electrodes at different states of charge were obtained. It was observed that Co₃O₄-based anode with the PEDOT: PSS/CMC binder has the lowest charge transfer resistance (R_ct), which indicates improving the kinetics of the electrochemical reaction. Furthermore, the presence of a linear part in the impedance spectra allowed for the qualitative evaluation of diffusion limitations. The values of the Warburg constants, as well as the associated diffusion coefficients of lithium ions, are the smallest for the Co₃O₄/PEDOT: PSS/CMC electrode compared to the other two electrode materials, which means improving the ionic conductivity of the electrode composition. Thus, it can be concluded that the improved functional properties of electrodes based on Co₃O₄ with PEDOT: PSS are associated with faster electronic and ionic transport of charge carriers.