Journal of Solid State Electrochemistry最新文献

In this study, lidocaine-tetraphenylborate (LD-TPB) ion-pair was synthesized using lidocaine hydrochloride (LD.HCl) and sodium tetraphenylborate (NaTPB), and a new all-solid-state type polyvinyl chloride (PVC)-membrane lidocaine-selective (LD-selective) potentiometric microsensor was developed by using this ion-pair as ionophore material in the PVC-membrane structure. The potentiometric performance characteristics of the LD-selective microsensor were investigated. The response time of the proposed microsensor was determined as ≤ 12 s, and the detection limit was determined as 5.49 × 10⁻⁷ mol.L⁻¹. The microsensor showed no significant drift in its potentials over seven weeks and showed a Nernstian response with a slope of 59.1 ± 0.7 mV/decade (R²: 0.9995) in the concentration range of 1.0 × 10⁻⁶ to 1.0 × 10⁻¹ mol.L⁻¹ for LD.HCl. It was determined that the microsensor had optimum performance in the pH range of 4.0–7.0. The LD-selective microsensor was successfully used for the potentiometric determination of LD.HCl in pharmaceutical samples. The potentiometric results were statistically compared with the results obtained by the UV–Vis spectroscopy method. The potentiometric results obtained were found to be in good agreement with the results obtained by the UV–Vis spectroscopy method at the 95% confidence level.

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Solid-state electrochemical sensors based on yttria-stabilized zirconia (YSZ) are commonly used in various industrial applications to analyze gaseous media. One of the important industrial tasks is the determination of carbon monoxide content in various gas environments at elevated temperatures. This work describes the preparation and characterization of an amperometric solid electrolyte sensor, which is used to measure the carbon monoxide content in inert gases (nitrogen, argon, and helium) at temperatures ranging from 600 to 700 °C. The sensor exhibited a linear relationship between the limiting current as a sensor reading and carbon monoxide concentration in the gas mixtures analyzed within the range of 1 to 10 vol.% CO. The diffusion coefficients of carbon monoxide in nitrogen, helium, and argon were also assessed using the obtained limiting current values. The dynamic characteristics of the sensor used to measure carbon monoxide content were obtained and confirmed to be highly sensitive, with a fast response and reproducibility in all gas mixtures studied. Therefore, the proposed sensor construction can be utilized for CO analysis at elevated temperatures.

The lithium-phosphorus-thiohalides (LPSX) with superionic conduction are strong candidates for the new-generation solid electrolytes (SEs) in all-solid-state lithium-ion batteries (ASSLIBs). In this work, Li_6−xPS_5−xCl_1+x−yBr_y (LPSCB; 0 ≤ x ≤ 0.7; 0 ≤ y ≤ 1.7) was synthesized by a solid-state method in which the key raw material of Li₂S was prepared by an improved carbothermal reduction method without late decarbonization. The lattice flexibility and the degree of structural order are opposite effect and would lead to an optimum of the ionic conductivity at a composition of LPSCB. Li₆PS₅Br- and Li_5.5PS_4.5Br_1.5-based ASSLIBs had the best rate capacity and cycle performance in Li₆PS₅Cl_1−yBr_y- (0 ≤ y ≤ 1) and Li_5.5PS_4.5Cl_1.5−yBr_y-based ones (0 ≤ y ≤ 1.5), respectively. To increase the ionic conductivity of LPSCB-type SEs and capacity/cycle performance of the related ASSLIBs, Br-introduction, mutual substitution and excess-X substitution were extremely effective strategies.

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Development of facile and cost-effective methods for the preparation of electrode materials are highly important for commercial energy storage and conversion applications. Herein, we develop a liquid-free synthesis of nickel cobalt oxide (NiCo₂O₄) nanostructures using a simple mixing and pyrolysis of metal salt precursors. The liquid-free synthesized NiCo₂O₄ showed truncated rhombohedral morphology with good crystallinity and uniformity. The NiCo₂O₄ exhibited a maximum specific capacitance of 306.1 F/g at 1 A/g with battery-like redox behaviour with good rate capability. Additionally, the faradaic electrode showed good cycling stability with a capacitance retention of 96.3% after 10,000 charge–discharge cycles. Furthermore, the NiCo₂O₄ nanostructures was used as an electrocatalyst, which showed superior electrocatalytic performance in alkaline electrolyte with a low Tafel slope of 80 mV/dec and reduced charge-transfer resistance. These electrochemical features are attributed to the porous interconnected nanostructures, good electrochemical active sites, and efficient ion/electron transport provided by NiCo₂O₄ electrode. Overall, the dry-synthesis method is scalable, and eliminates hazardous solvents, making it is ideal for large-scale production of electrode materials for next-generation energy storage and conversion applications. 

One promising method of converting solar power into chemical fuel and minimizing power shortages is photoelectrochemical water splitting, which can produce hydrogen and improve environmental health. Au functionalized In₂S₃ nanoflowers were synthesized with an easy chemical vapor deposition (CVD) and chemical reduction technique, respectively. Surface characterization techniques such as Field effect scanning electron microscopy (FESEM) and Elemental mapping analysis (EDX) show the uniform functionalization and synthesis of Au functionalized In₂S₃. High optical absorption and higher electron–hole pair concentration are generated due to an in-built electric field, reducing the recombination rate at the interface and resulting in a high photocurrent density value of 5.5 mAcm⁻² and IPCE (incident photon to the current conversion efficiency) value of 80%. The synthesized Au functionalized In₂S₃ nanoflowers demonstrated excellent durability and functionality for the oxidization process of water in sunlight.

Stainless steels are alternative materials for graphite bipolar plates in proton exchange membrane (PEM) fuel cells. Plasma electrolytic nitriding (PEN) of stainless steel 316L samples was carried out in an aqueous solution of urea. Grazing incidence X-ray diffraction analysis revealed the presence of Fe₂N_0.94, iron oxide, and X-ray photoelectron spectroscopy results showed iron nitride, iron oxide, and chromium oxides on the PEN-modified 316L surface. The thickness of the modified layer is approximately 1.1 μm as determined with glow discharge optical emission spectroscopy. The PEN-modified surface exhibited a lower corrosion current density of 88 ± 15 µAcm⁻² and 57 ± 16 µAcm⁻² in the simulated anodic and cathodic environments, while bare samples showed a corrosion current density of 155 ± 31 µAcm⁻² and 156 ± 15 µAcm⁻² in respective environments. Electrochemical impedance spectroscopy at open circuit potential revealed that PEN-modified surface has more polarization resistance than bare samples, indicating improved corrosion resistance. However, the long-term potentiostatic studies for 8 h showed that PEN-modified samples have higher passive current densities of 17.7 µAcm⁻² and 4.2 µAcm⁻² in anodic and cathodic environments, whereas bare samples showed 1.4 µAcm⁻² and 0.6 µAcm⁻² in respective environments. The concentration of total dissolved metal ions after potentiostatic polarization is significantly reduced after PEN modification, where the PEN-modified samples showed only 2.37 mgL⁻¹ and 5.54 mgL⁻¹ in anodic and cathodic environments, while bare samples showed 16.99 mgL⁻¹ and 20.24 mgL⁻¹ in respective environments. Interfacial contact resistance (ICR) values for bare and PEN-modified 316L at a compaction load of 140 Ncm⁻² were 118.8 ± 4.6 mΩcm² and 26.8 ± 3.7 mΩcm², respectively.

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In this study, a multi-scale grain distribution was achieved in 0Cr17Ni13Mo5 super austenitic stainless steel through severe cold rolling followed by annealing at temperatures ranging from 500 to 1000 °C. The effects of this hierarchical microstructure on corrosion resistance were systematically investigated. The results show that the sample annealed at 1000 °C exhibits the best corrosion resistance, with a corrosion potential (E_corr) of − 0.12 V_SCE, a corrosion current density (j_corr) of 7 × 10⁻⁸ A/cm², and a polarization resistance (R_t) of 1,022,600 Ω·cm². Mott–Schottky analysis confirms that the 1000 °C annealed sample had the lowest donor density and the slowest corrosion rate, further supporting its superior corrosion resistance. This enhancement is primarily attributed to the formation of a bimodal grain structure, which facilitates the diffusion of Cr atoms toward the corroded surface, promoting the formation of a thicker passive film. In addition, annealing at 1000 °C reduces the precipitation of σ-phase at grain boundaries. Furthermore, the higher fractions of Σ CSL boundaries and Σ3 twin boundaries contribute to improved resistance to intergranular corrosion. 

In this study, we use density functional theory (DFT) with a Hubbard (U) parameter, implemented in the Quantum Espresso code, to investigate the interactions between Li-ions and the ZrS₂ monolayer under the influence of in-plane uniaxial and biaxial strains, specifically within the context of lithium-ion batteries. This is to ensure the ZrS₂ monolayer is more robust against the Coulomb forces arising from interactions between multiple lithium ions. This study objectively examines the impact of tensile and compressive strains ranging from − 5% to 5% on the energetic stability and electrochemical properties of the lithiated ZrS₂ electrode monolayer. For a single Li adatom on a 3 × 3 ZrS₂ monolayer, the compressed structure (at − 5% strain) becomes more energetically favorable, exhibiting a low adsorption energy of − 1.41 eV. In contrast, the stretched structure (at + 5% strain) has a higher adsorption energy of − 0.95 eV compared to the unstrained structure (− 1.16 eV), although exothermic interaction is maintained. The ZrS₂ electrode monolayer has a shallow energy barrier of 0.23 eV for Li-ion diffusion, indicating greater mobility, which is slightly enhanced by compressive strain. The application of − 5% (compressive strain) resulted in an average OCV of 0.93 V, and 0.78 V for unstrained, while + 5% (tensile strain) yielded an OCV of 0.69 V, which is in the range of commercial anode materials. The tensile strain on a ZrS₂ electrode monolayer would be more effective in mitigating the dendrite formation. The introduction of a Li adatom rearranged the conduction band minimum, leading to the hybridized Zr d orbital states crossing the Fermi level and becoming more populated as the number of Li adatoms increases, leading to a more conductive electrode. Additionally, the strain reduced the band gap, causing the induced electronic states to be continuous from the VBM to the CBM edges, which enhances the electronic conductivity of the material, ensuring the excellent LIBs operation during the charge and discharge processes.

Single-walled carbon nanotubes (SWCNTs), renowned for their excellent electrical conductivity, have long been recognized as an ideal conductive additive material. However, the high-quality and high-yield preparation of SWCNTs remains a significant challenge. In this study, we report the use of a catalyst consisting of magnesium oxide (MgO) as the substrate, with nickel (Ni) and tungsten (W) as the catalytic elements. After calcination, the catalyst formed a MgNiO₂ phase, which was then utilized in the chemical vapor deposition (CVD) method to prepare SWCNTs. The catalyst efficiency of SWCNTs reached 116% (the mass ratio of SWCNTs to catalyst). After acid treatment to remove metal impurities, the SWCNTs were incorporated as a conductive additive (5 wt%) in LiFePO₄ (LFP) lithium-ion batteries. The results demonstrate that the batteries containing this SWCNT conductive additive exhibited exceptional cycling and rate performance. At a 5 C discharge rate, the specific capacity reached 115.51 mAh/g. The capacity is still 123.93 mAh/g after 200 cycles at a 3 C discharge rate, with a retention rate of 90.90%. This test group had the lowest charge transfer impedance and the highest ion mobility rate when compared to the commercial carbon nanotubes and SuperP (SP) conductive agent control group. The findings of this study provide a simpler and more efficient method for the preparation of SWCNTs.