Journal of Solid State Electrochemistry最新文献

This study investigates the electrochemical behaviors of ZnWO₄, δ-FeOOH, and ZnWO₄/δ-FeOOH anodes in 0.1 M sulfate and hydroxide electrolytes, emphasizing the influence of SO₄²⁻ and OH⁻ on electrode performance. Impedance data demonstrated that the ZnWO₄/δ-FeOOH composite exhibited the highest charge transfer response, signifying enhanced charge migration and capacitive capability with respect to the pristine electrodes. In Na₂SO₄, SO₄²⁻ steadied the interfacial capacitance and enhanced ion transport, whereas in NaOH, the presence of high electrical mobility and portable OH⁻ substantially enhanced charge relocation and diffusion, establishing NaOH as an additional efficient electrolyte than Na₂SO₄ for photoelectrochemical activity. Tafel analysis indicated superior electron movement and energy performance in NaOH, utilizing a hybrid electrode outperforming its counterparts when placed in both solutions. Sweep voltammetry confirmed a joint effect of ZnWO₄ and δ-FeOOH, yielding a current of 5.94 mA·cm⁻² in NaOH under illumination, reflecting a ~ 22-fold increase with respect to that obtained in Na₂SO₄. Furthermore, the ZnWO₄/δ-FeOOH composite exhibited long electron lifetimes in NaOH, attributable to the small ionic size and the elevated diffusion rate of OH⁻. Intermittent current measurements shown considerable enhancements in induced current production and constancy in NaOH. These results highlight that the ZnWO₄/δ-FeOOH structure is a more effective and steady structures for cutting-edge energy applications, with NaOH shows the most favorable situations for obtaining enhanced electrochemical performance.

This study investigated the corrosion characteristics of weathering steels (WSs) with varying nickel contents in a simulated marine atmosphere, as well as the primary mechanism of action for nickel (Ni) during the corrosion process, by combining electrochemical methods and microanalytical techniques. The research findings reveal that the corrosion scales of nickel-containing steels exhibit better compactness compared to carbon steel, along with a distinct layered structure. Notably, the compactness of the corrosion scale increases with higher nickel content, effectively inhibiting the diffusion of Cl⁻ within the inner rust layer. The primary components of the corrosion scale are identified as α-FeOOH, γ-FeOOH, Fe₃O₄, and Fe₂O₃. With increasing Ni content, the proportions of α-FeOOH and γ^*(γ-FeOOH, Fe₃O₄, and Fe₂O₃) in the corrosion scale are observed to rise. The corrosion process of the specimens is divided into two stages. Within the first 60 days, the polarization resistance (R_p) values of the specimens initially decrease and then gradually increase with the extension of corrosion time, which is attributed to the destructive effect of Cl⁻ on the corrosion products and the subsequent formation of a corrosion scales. The R_p values of carbon steel are higher than that of weathering steel, since Ni in WS reduces the corrosion rate of the specimens and delays the formation of the protective corrosion scale on their surfaces. Specifically, the higher the nickel content, the greater R_p value WSs, indicating that Ni is beneficial for retarding the corrosion rate of the sample. After 60 days of corrosion, the R_p values of WSs exceeds that observed in the earlier stage, which is associated with the formation of a stable corrosion scale in WSs. With prolonged corrosion time, the R_p values of WSs decreases, a trend linked to the destructive effect of Cl⁻ on corrosion scales. In summary, the R_p values of WSs are significantly superior to that of carbon steel, and this superiority strengthens with increasing nickel content. This enhancement is primarily ascribed to the improved compactness of the corrosion scale and the inhibited Cl⁻ penetration in corrosion scales induced by Ni.

Major bottleneck present in the scalability of enzymatic glucose fuel cells (EGFCs) is the complex interdependency of various factors such as mass transport, reaction kinetics and electron transfer mechanisms leading to loss in performance. Mathematical modeling using dimensionless quantities is crucial as it aids in quantifying the various losses present in EGFCs. A model is developed using Damkohler number (Da) to study the substrate transport – reaction interactions considering the deactivation of enzymes in mediated EGFCs. The variation of Da with operating parameters such as substrate and enzyme concentration, length and porosity of the electrode, and operating temperature is modeled. Modeling results indicate that initially Da increases with substrate concentration. However beyond a certain substrate concentration, the Da is found to decrease. Da is found to increase with increasing enzyme concentration, electrode porosity and length. The performance of EGFCs is evaluated using the variation in electrode overpotential and current density. The model is found to be compliant with the literature data.

“Electrical double layer” (EDL) effects on electrode kinetics are re-gaining increasing attention in various fields. While equilibrium EDLs are assumed in most studies, EDLs can be brought away from equilibrium by electrode reactions. Levich is considered to pioneer the theory of nonequilibrium EDL; however, his 1949 original text has not been translated in the public into English domain, and the translation of the less known subsequent 1959 article is rarely available. We translate Levich’s original works, provide the historical background, put them in the context of subsequent developments, and correct a few theoretical details. The interaction of Levich’s nonequilibrium EDL theory and the attempts to apply it to the interpretation of experimental results of the same period are of high scientific value nowadays, in view of the gap between theory and experiments. Finally, we discuss the links between this idea and some relevant research topics in modern interfacial electrochemistry.

Titania nanotubes (TNT) photoanodes were fabricated by anodization of titanium foil at 60 V in ethylene glycol-based electrolyte employing two-step procedure. The obtained TNT/Ti photoanode consists of anatase polymorph of titania, forming nanotubes with length of 20–22 µm, average diameter of 90–100 nm and wall thickness of 20 nm. The performance of this photoanode in the photoelectrocatalytic oxidation of two nonsteroidal anti-inflammatory drugs (NSAIDs)—ketoprofen (KET) and ibuprofen (IBP)—in a saline solution was studied. Ultra Performance Liquid Chromatography–Mass Spectrometry (UPLC-MS) was used for identification of degradation products after the first stage of the photoelectrochemical degradation. It is shown that photoelectrocatalytic oxidation of these compounds proceeds with formation of intermediate oxygenated forms; some of them could be more toxic than the initial NSAIDs. The principal degradation products are represented by alcohols and ketones; chlorinated derivative of ibuprofen is also observed.

Garnet-type electrolytes are pivotal for developing safe, high-capacity all-solid-state lithium batteries (ASSLBs), yet their advancement is critically impeded by the poor physical contact and consequent high impedance at the lithium metal anode/electrolyte interface. Herein, we report a facile yet effective interface engineering strategy by modifying the surface tension of molten lithium. Introducing a mere 0.1 wt% of gallium (Ga) into the Li anode—a quantity that negligibly affects its theoretical specific capacity—dramatically enhances its wettability against the garnet electrolyte. This modification forges an intimate and stable Li-Ga/garnet interface, achieving an exceptionally low area-specific resistance (ASR) of 5.5 Ω cm² at 30 °C. Consequently, symmetric batteries with the modified anode demonstrate a high critical current density (CCD) of 1.15 mA cm^-2 and remarkable cycling stability, operating for over 1000 h at 0.3 mA cm^-2 without failure. This work demonstrates that trace-element alloying is a highly effective strategy for resolving the interfacial challenges in garnet-based ASSLBs, paving the way for their practical implementation.

With the advancement of electric vehicles and portable electronic devices, the market has increasingly stringent requirements for the energy density and safety of lithium-ion batteries. As a result, solid electrolytes with high energy density and enhanced safety have emerged. Among these, garnet solid electrolytes are considered one of the most promising materials due to their high electrochemical stability and wide electrochemical window. However, they are unstable in air, susceptible to Li⁺/H⁺ exchange reactions, and can further react with CO₂ in the atmosphere to form lithiophobic Li₂CO₃ layers. In recent years, researchers have proposed various solutions to address this issue. This article will briefly introduce some of these approaches, including mechanical polishing, acid treatment, heat treatment, and in-situ reaction treatment. Currently, the methods for removing surface lithium carbonate through mechanical polishing, acid treatment, and heat treatment still exhibit certain limitations, while in-situ reaction treatment shows significant potential for improvement and it will become the focus of future research.

Two-dimensional ceramics-based materials exhibit fascinating performance in the electrochemical field in recent years. In the present contribution, the electronic performance of the Nb₂CO₂/Si₃N₄ heterojunction as an anode material are systematically investigated by the first principles calculations. The structural stability of the Nb₂CO₂/Si₃N₄ heterostructure is verified by a negative binding energy, indicating favorable energetic stability. Moreover, the heterostructure demonstrates excellent electrochemical kinetics, with ultra-low diffusion energy barriers of 0.231 eV for Li ion and 0.316 eV for Na ion. With the increase of Li and Na ions concentrations, the average adsorption energy of the heterostructure is -0.12 eV and -0.53 eV, respectively. The theoretical specific capacity reaches 429.73 mAh/g for Li and 330.46 mAh/g for Na, surpassing that of conventional graphite anodes. Furthermore, the average open-circuit voltage (OCV) at maximum loading is 0.41 V and 0.35 V, which is within the reasonable expected range, thus ensuring the safety of the electrode material. These results show that Nb₂CO₂/Si₃N₄ has great potential as anode materials for metal ion batteries. The gradient boosting regression (GBR) algorithm with R² of 0.91 is the most accurate for predicting adsorption energy by using the method of machine learning, followed by random forest (RF) with R² of 0.897 and support vector regression (SVR) with R² of 0.848. This high accuracy confirms the robustness of the descriptors, providing a valuable framework for the accelerated design of high-performance anode materials.

This survey focuses on in-situ studies of solid oxide fuel cells (SOFCs) and other solid oxide electrolyte devices using Raman spectroscopy, which is often combined with other electrochemical and physical methods. Most conventional techniques, for example, structural and microscopy techniques and methods of elemental analysis, cannot provide an opportunity to conduct in-situ analysis of the processes that occur in the materials, electrodes, and entire SOFCs due to high operating temperatures (up to 850–900 °C), high current densities (often up to the level of several A/cm²), aggressive gas environments, and separated cathode and anode gas chambers. Conventional electrochemical techniques cannot provide the local information. On the contrary, Raman spectroscopy enables remote, noninvasive, local and molecular-sensitive testing of SOFCs, thus making it possible to obtain information on the macro- and microscopic mechanisms and to perform targeted optimization of the composition, microstructure, and operating conditions of SOFC components. This review aims to cover recent research focused on separate SOFC materials, electrochemical half-cells, and full SOFCs. Special attention is given to carbon deposition at SOFC anodes fueled with hydrocarbon-containing mixtures, mechanisms of hydrocarbon electrooxidation, anode reduction kinetics, poisoning with S- and Cl-containing impurities, variations in oxygen chemical potential, and assessment of emerging mechanical stresses.