Journal of Solid State Electrochemistry最新文献

The electrochemical behavior of two nineteenth and twentieth century grey cast iron alloys was studied in 0.5 M and 1 M phosphoric acid solutions, with sodium dodecyl sulfate (SDS) used as a corrosion inhibitor. The influence of temperature on the corrosion process, the critical micellar concentration (CMC) of SDS, and its inhibition efficiency were evaluated using conductimetry, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization and inductively coupled plasma-optical emission spectrometry (ICP-OES). Two samples of grey cast iron, GCI-A and GCI-B, were studied. The presence of varying percentages of copper and manganese in the chemical composition of grey cast iron enhances its corrosion resistance. In phosphoric acid solutions, the surface charge of grey cast iron becomes negative in the presence of SDS molecules, as SDS adsorbs onto the metal surface through both chemical and physical interactions, acting as a mixed-type inhibitor by blocking anodic and cathodic reaction sites. Increasing the phosphoric acid concentration decreases the critical micellar concentration (CMC) of SDS, whereas an increase in temperature has the opposite effect. The addition of SDS at a concentration of 10⁻⁴ M significantly reduces iron dissolution in both grey cast iron alloys studied. Consequently, SDS decreases both anodic and cathodic current densities, effectively inhibiting the corrosion process of grey cast iron in phosphoric acid solutions, with an inhibition efficiency of approximately 95%. SEM analysis revealed that SDS protects the grey cast iron surface by reducing the size and density of graphite flakes. The inhibitive properties of SDS highlight its potential importance in the conservation and restoration of grey cast iron objects.

Corrosion of steel reinforcement is a key issue affecting the durability and service life of marine concrete structures. To develop a more accurate predictive model for the corrosion rate of steel reinforcement, this study conducted a series of experiments. Specimens with different rebar diameters and concrete cover thicknesses were prepared, and NaCl was added in varying amounts (0 to 0.6%, based on the binder mass, increasing by 0.1%). Two parallel sets of six specimens each (covering different combinations of rebar diameters and cover thicknesses) were made for each NaCl dosage, totaling 84 specimens. The linear polarization resistance (LPR) method was used to test these specimens under the same conditions. The results showed that the relative and absolute corrosion current densities of steel reinforcement in marine concrete generally follow a normal distribution, confirming the reliability of the current research approach. The study also analyzed the effects of free chloride content (({C}_{text{f}})), cover thickness (C), rebar diameter (D), and exposure time (t) on the corrosion rate. The corrosion current density (({I}_{text{corr}})) increases with higher free chloride content but decreases with thicker concrete cover, larger rebar diameter, and longer exposure time. Based on these findings, a comprehensive predictive model for the corrosion rate of steel reinforcement in marine concrete structures was developed and validated through significance tests. This model provides a scientific basis for the design and maintenance of marine infrastructure, enhancing the durability of reinforced concrete structures in harsh marine environments.

Thermoelectrochemical cells (also known as thermogalvanic cells or thermocells) are electrochemical devices that convert thermal energy to electrical energy via entropically driven redox reactions. These devices have gained increasing attention this century as they have the possibility of valorising otherwise wasted (heat) energy to useful (electrical) energy with no moving parts, no greenhouse gas emissions, and using sustainably sourced elements such as iron (Fe). Liquid thermocells suffer from several issues including electrolyte leakage, lower ‘observed’ temperature gradients than those applied and poor mechanical properties. Towards applications such as body heat harvesting — where thermal energy sources are dynamic — these disadvantages can become significant. Gelled electrolyte thermocells have been developed as these are self-contained systems that achieve higher temperature gradients across the thermocell and have mechanical properties that allow the ability to stretch, bend, and twist. This makes gelled thermocells compatible with many of the proposed applications of these devices. However, compared to liquid electrolyte thermocells, gelled electrolyte thermocells typically achieve significantly lower performance, mainly due to frustrated ion transport in the denser matrix, reducing the generation of current, which also leads to reductions in power output over time. This review provides an overview of the current state of gelled electrolyte thermocells and compares them to their liquid counterparts.

In this work, pristine and Ag-modified lanthanum succinate polymeric composites were prepared as selective electrochemical sensors for the monitoring of mercury (Hg²⁺) in aqueous media. Furthermore, Ag-modified La-succinate sensor effectively distinguished Hg²⁺ ions from potentially disruptive metal species. It has R² = 0.995 and a Freundlich adsorption capacity of 2.3 mg/g. The measurements of electrochemical impedance were also employed to evaluate resistance due to charge transfer. The sensitivity of the sensor is optimized for the lowest concentration of Hg²⁺ ions in the aqueous media with limit of detection (LOD) of 0.1 nM. The reported LOD for Hg²⁺ ions is well below the prescribed limit for the drinking water as per the World Health Organization. The reliability of this sensor was confirmed by evaluating its sensitivity (4.4 μAM⁻¹) and its selectivity for Hg²⁺ ions. In addition to this, the sensor has very good electrochemical stability and repeatability for the repeated exposures of the same concentration of Hg²⁺ ions. These notable parameters of Ag-modified La-succinate electrochemical sensor show its potential for detecting hazardous Hg²⁺ ions.

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The sponge-like hydrogenated titania nanotubes (S-TiO₂-NTs) modified with M13 bacteriophages were investigated for bacterial detection. The electrodes used in this study were fabricated via anodisation and calcination in a hydrogen atmosphere. Electrochemical methods were used to study the capacitive and Faradaic currents of the S-TiO₂-NTs electrodes in varying concentrations of M13 phage lysate immobilised through physisorption. Moreover, measurements over time, at 37 °C and in human serum, were performed to evaluate the stability of the phage-modified electrodes. The obtained results demonstrated that the phages were successfully adsorbed on the electrode surface, which was also confirmed by scanning electron microscopy. Furthermore, the S-TiO₂-NTs with wild-type M13 phage were used to detect E. coli bacteria. The limit of detection (LOD) for the electrode was LOD = 3 cells/mL, and the linear range was 10–10⁴ cells/mL. The results demonstrate that S-TiO₂-NTs electrodes are promising immobilisation platforms for M13 phage.

One of the most critical processes in the production of lead-acid batteries is the electrochemical formation of the plates. In the case of VRLA (valve-regulated lead-acid) batteries with glass mat separators, this process is carried out post-assembly, after the plates are sealed in the battery casing and sealed with a lid. AGM (absorbed glass mat) batteries are initially filled with electrolytes and placed in water baths, where the formation process begins. The use of water baths is essential for temperature control, due to the highly exothermic nature of the formation process. Temperature management during formation is a key factor due to its impact on several key parameters, including PbO₂ conversion factor, water loss, and potential degradation of additives, such as lignosulfonates, in the plates. Excessively high temperatures can adversely affect the integrity of these additives, negatively impacting battery performance and life. The presented research focuses on the effect of temperature during the formation process on the basic electrical properties of AGM batteries and the chemical properties of the positive and negative plates after this stage. The research aimed to optimize the formation process in order to increase process efficiency.

Prussian white and its analogues are regarded as promising cathode candidates for sodium-ion batteries because of their high capacity, facile synthesis and abundant resource. However, their cyclic lifespans are limited. One of the main reasons is the complex phase transformations of their crystal structure during the insertion/desertion of sodium ions. Herein, nickel-doped manganese-based Prussian white composited with carbon nanotubes were synthesized with the aim to stabilize crystal structure during charging/discharging and consequently enhance cyclic performance. Structural and chemical characterizations indicate that the doped nickel atoms occupy lattice sites of manganese. Electrochemical evaluations indicate that the obtained cubic-structured Na_1.55Mn_0.94Ni_0.06[Fe(CN)₆]_0.92∙2.74H₂O/carbon nanotubes delivers a reversible capacity of 98 mAh g⁻¹ with an initial coulombic efficiency of 97% at 1C and still maintains 64 mAh g⁻¹ after 400 cycles. Serial ex situ X-ray diffractions disclose that the nickel-doped manganese-based Prussian white maintains its cubic structure during the insertion/desertion of the sodium ions. No phase transformation is observed except a little variation of the lattice constants. The structural stability enables high cyclic stability. Nickel doping and carbon nanotube composition are efficient ways to improve the electrochemical performance of the manganese-based Prussian white for sodium-ion batteries.

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The results of extensive, continuous research have significantly improved the performance of commercial lithium-ion batteries. An essential part of lithium-ion batteries is the cathode materials, which are used to regulate the cost, energy density, and operating voltage. Researchers have been looking for and altering different cathode materials over the last few decades. Compounding, coating, elemental doping, and other modification techniques are a few examples. Based on an overview of the operation of lithium-ion batteries, this paper systematically discusses the structural properties and modification of lithium battery cathode materials, such as LiCoO₂, LiFePO₄, LiMn₂O₄, and ternary materials. This review seeks to provide information on the direction of technological development in lithium-ion batteries, increase battery power and capacity, reduce the cost of lithium-ion batteries, and maintain and improve safety to better address the problems that society faces. It also discusses upcoming research on other popular lithium-ion cathode materials.