Journal of Solid State Electrochemistry最新文献

Due to its excellent conductivity and corrosion resistance, NiCu alloy has been extensively studied and utilized by researchers. However, existing research primarily focuses on the corrosion rate, current efficiency, and aluminum product purity of inert anodes, with limited detailed analysis of the corrosion mechanism. This study investigates the corrosion behavior of NiCu alloy in a Na₃AlF₆-AlF₃-Al₂O₃ system using cyclic voltammetry, potentiodynamic polarization, X-ray diffraction, and scanning electron microscopy. Pure Ni, pure Cu, and an equiatomic NiCu alloy were selected as samples, and the corrosion resistance of the NiCu alloy was evaluated through electrolytic experiments. The results reveal that the corrosion resistance of NiCu alloy surpasses that of both Ni and Cu. A mixed oxide layer consisting of Cu₂O, NiO, and NiAl₂O₄ was formed on the surface of the NiCu alloy, effectively protecting the anode substrate while maintaining the stability of the electrolytic voltage. After electrolysis at a current density of 1 A/cm² for one hour, the thickness of the corrosion layer was measured to be 21.3 μm. Additionally, the presence of aluminum oxide was found to enhance the protection of the inert anode during electrolysis.

Porous anodic aluminum oxide (AAO) films with thicknesses exceeding 500 μm present significant potential for advanced X-ray optical applications. However, the stable, long-duration fabrication of such thick films requires overcoming process limitations, such as voltage rise and thickness non-uniformity, which are governed by the complex role of electrolyte additives like ethylene glycol (EG). This study systematically elucidates the time-dependent trade-off of EG by decoupling its competing positive and negative mechanisms. We demonstrate that the primary benefit of EG is its improved wettability, which promotes O₂ gas bubble detachment at the pore bottoms. This mechanism—not enhanced ion circulation—is the true cause of the observed improved thickness uniformity, as it prevents local reaction passivation. Conversely, the primary cost of EG is its high viscosity, which hinders ion transport (diffusion). This leads to concentration polarization at the pore bottoms, causing a significant (non-ohmic) voltage rise that becomes rate-limiting during long-duration growth. We further show that this “cost” (polarization) can be mitigated by increasing the oxalic acid concentration (e.g., to 0.5 M), which enhances the diffusive flux of reactants. This mechanistic framework enables a practical operating window (0.5 M oxalic acid, 20 vol.% EG) for the stable, burn-free fabrication of thick (> 500 μm), uniform porous AAO films, paving the way for their application in X-ray optics and other fields.

The detection of perchlorate in some environmental and medical samples has been investigated by various research groups. However, due to its low detection limit and wide operating range, sensitive and selective perchlorate detection presents several challenges and requires costly analytical methods. In this study, methyltrioctylammonium chloride (MTOAC) was successfully used as an ionophore for the determination of perchlorate (ClO₄⁻). The MTOAC ionophore-containing sensor demonstrated superior potentiometric properties, including a fast response time of 15 s, a wide linear operating range of 1.0 × 10^− 2 to 7.5 × 10^− 8 M, a low detection limit of 6.8 × 10^− 8 M, a wide pH operating range of 3.36–9.65, and high repeatability at perchlorate concentrations of 10^− 4 to 10^− 6 M. Additionally, the MTOAC sensor showed high recovery (99.4-102.3%) in different water samples obtained from tap water, wastewater, spring water and Van Lake water. Compared to the sensors reported in the literature, the MTOAC sensor exhibited a wider linear working range and a lower detection limit. The low production cost, short response time, the absence of pretreatment, ease of use without requiring expertise, and the ability to operate even in turbid solutions make the MTOAC ionophore-containing membrane-based sensor a promising alternative for practical analytical applications.

To meet the development demands of high-energy-density, long-cycle-life lithium-ion batteries, this study focuses on the development of high-performance electrolyte additives, and has successfully synthesized and systematically characterized a novel lithium salt additive lithium tetrafluorophosphate (LiPOF₄). By optimizing the reaction process between silicon tetrafluoride (SiF₄) and phosphorus pentoxide (P₂O₅), the critical intermediate phosphorus trifluoride (POF₃) was successfully prepared using the gas-phase contact method, which was then reacted with lithium fluoride (LiF) to synthesize LiPOF₄. SEM and TEM results showed that the obtained LiPOF₄ was predominantly amorphous in nature. Thermogravimetric analysis confirmed that the material exhibits excellent thermal stability, with a significant decomposition temperature of 310 °C. Electrochemical testing revealed that adding 10 wt% LiPOF₄ to the electrolyte significantly enhances the performance of lithium-sulfur batteries: after 100 cycles at a 0.5 C rate, the coulombic efficiency was 83.7% (compared to 77.1% for the control group), the charge specific capacity was 594.7 mAh/g (control group: 534.7 mAh/g), and the discharge specific capacity was 755.1 mAh/g (control group: 697.4 mAh/g). Additionally, the addition of LiPOF₄ effectively extended the charge-discharge plateau of the lithium-sulfur battery. This work provides new materials and new ideas for improving electrolyte performance.

Lithium-sulfur (Li-S) batteries are considered promising candidates for next-generation energy storage technologies due to their high theoretical energy density. However, the instability of the lithium anode and the sluggish redox kinetics of sulfur significantly hinder their practical application. To overcome these challenges, the development of electrolyte additives with dual functions, protecting the lithium anode and promoting sulfur redox reactions has emerged as a key strategy for breaking through current performance bottlenecks. In this study, the effect of 6-bromohexanenitrile (BHN) as a bifunctional electrolyte additive on Li-S battery performance is investigated. The findings reveal that the bromo terminal group in BHN participates in the formation of the SEI layer on the lithium anode, generating inorganic compounds such as LiBr, thereby enhancing interface stability, suppressing lithium dendrite growth, and protecting the lithium anode from side reactions with polysulfides. Furthermore, density functional theory (DFT) calculations show that the BHN additive can effectively modulate the molecular orbital energy levels of lithium polysulfides, resulting in reduced molecular orbital energy gaps and enhanced redox activity. This accelerates polysulfide interconversion and effectively improves interfacial reaction processes. Li-S cells incorporating BHN exhibit an initial discharge specific capacity of 1360 mAh g^− 1 at a 0.1 C rate. Moreover, at a current density of 0.2 C, the cells demonstrate excellent cycling stability, retaining 80.4% of their capacity after 120 charge-discharge cycles. This work presents a new strategy for the design of high-performance lithium-sulfur battery electrolytes and provides valuable theoretical insights into the development of bifunctional electrolyte additives.

Mesoporous δ-MnO₂/MnC₂O₄·3H₂O hybrid materials have been prepared by fast room temperature redox deposition method using ascorbic acid as reducing agent. The products were characterized by powder X-ray diffraction, Fourier transform infrared and Raman spectroscopy, scanning electron microscope, low-temperature nitrogen adsorption and thermogravimetric analysis. The BET surface area of hybrid materials depends on their composition and ranges between 133 and 275 m² g^− 1. When used as an electrode for pseudocapacitors, δ-MnO₂/MnC₂O₄·3H₂O hybrid materials show very good electrochemical performance. The sample containing the minimum amount of δ-MnO₂ showed the maximum initial specific capacitance of 240 F g^− 1 at current density of 1 A g^− 1. After 500 cycles the specific capacitance for sample exhibits 97% of the initial capacity indicating its high stability. The high specific capacitance and cycling performance of the hybrid materials are attributed to synergistic effect between δ-MnO₂ and MnC₂O₄·3H₂O. The electrochemical tests demonstrate that δ-MnO₂/MnC₂O₄·3H₂O hybrids exhibit satisfactory properties as an anode materials for lithium-ion batteries.

Supercapacitors have achieved rapid development in the energy storage field with advantages such as high power density, fast charge-discharge rate, eco-friendliness, and low cost. This paper studied the preparation of CC/NiFeP@NiFeN composite electrode material and its supercapacitor performance. CC/NiFeP@NiFeN composite electrode was prepared via in-situ phosphonitridation of CC/NiFe-LDH precursor by designing a heterogeneous interface. This electrode integrates the synergistic effect of stable and open structure as well as component interconnection, which accelerates the redox reaction kinetics and thus exhibits excellent electrochemical performance. The specific capacitance of the CC/NiFeP@NiFeN electrode was 526 F·g⁻¹ at a current density of 1 A·g⁻¹. An NiFeP@NiFeN//AC asymmetric supercapacitor was assembled using the CC/NiFeP@NiFeN electrode as the positive electrode and the AC electrode as the negative electrode. This supercapacitor exhibited a power density of 985.97 W·kg⁻¹ at an energy density of 44.91 Wh·kg⁻¹; even at a lower energy density of 32.66 Wh·kg⁻¹, it still maintained a high power density of 1.68 kW·kg⁻¹. After 5000 charge-discharge cycles, the capacitance retention rate of the device reached 98.4%.

With the development of new energy sources, the demand for lithium in the world is increasing, and the exploitation and utilization of lithium resources has become a urgent need. In the process of lithium salt production, a large amount of lithium precipitation mother liquor will be produced, which contains a large number of lithium resources. Due to its high Na⁺/Li⁺ ratio, it is difficult to extract Li⁺. The purpose of this paper is to study the performance of electrochemical lithium extraction method based on LiFePO₄-Pb oxide system in lithium precipitation mother liquor. The specific capacity of the system can reach 120 mAh·g^− 1 at 0.1 C. The system has good cycling performance in both high and low concentration Li₂SO₄ solution. The coulomb efficiency is basically above 90% in the rate test.It still has high selectivity for Li⁺ in lithium precipitation mother liquor with a Na⁺/Li⁺ratio of up to 10:1 (molar ratio), the concentration of Li⁺ in the mother liquor decreased by 21.12 mM and the concentration of Li⁺ in the extracting solution increased by 20.61 mM after three cycles. The average inserted capacity of Li⁺ was 20.1 mg/g and the extracted capacity was 19.6 mg/g. The separation coefficient of Li/Na is as high as 237.91. It can extract Li⁺ efficiently and has good recycling performance. It provides an advanced method for extracting Li⁺ from lithium precipitation mother liquor.

Gallium electrodeposition is currently limited by hydrogen evolution reactions (HER) in traditional electrolyte, which severely degrade current efficiency and deposit quality. This study investigates the electrodeposition of gallium (Ga) in a non-aqueous dimethylformamide (DMF) system containing 0.5 M GaCl₃ to eradicate HER and enable high-quality Ga deposition. Gallium deposits on different substrates exhibit distinct morphologies, among which the gallium particles deposited on copper substrates possess both spherical and strip-like structures. Through the analysis of the electrodeposition behavior and nucleation process of gallium on copper foil, an irreversible Ga deposition process with a cathodic charge transfer coefficient (α) of 0.0528 and a diffusion coefficient of 6.964 × 10⁻⁶ cm²/s, is confirmed during the electrochemical behavior and nucleation. The Ga nucleation shifts from an instantaneous model at -1.1 V to a progressive model at more negative potentials, reflecting potential-dependent growth dynamics. The deposition efficiency of gallium has been calculated to over 80% at low current density through the gravimetric method. These findings establish DMF as a promising solvent for efficient Ga electrodeposition, offering insights for applications in flexible electronics and energy storage technologies.

Graphical Abstract

In this work, TiO₂ thin films were fabricated on a gold-interdigitated silicon substrate by electrochemical anodization. The samples were annealed in air for 6 h at 450 °C and 550 °C, obtaining the coexistence of the anatase and rutile phases. The influence of the anatase/rutile phases ratio on the photoresponse at different wavelengths was analyzed. The optical and electrical properties, as well as the morphology of the TiO₂ thin film, were studied by scanning electron microscopy, X-ray diffraction, impedance spectroscopy, and UV–vis spectroscopy. Unlike most TiO₂ films, which exhibit good photoresponse only in UV light, we were able to extend the photoresponse to a wide range of wavelengths. Controlling the ratio of the anatase/rutile phases by annealing temperature significantly improved the sensitivity of the thin film. It was observed that the sample with approximately 80% anatase phase by weight exhibited a better photoresponse than the sample with a reduced anatase value of 25%. In particular, sensitivity increased by an order of magnitude.