Journal of Solid State Electrochemistry最新文献

Herein, we reported the synthesis of MnO₂/ZIF-8 composite by employing two-step synthetic procedure. The synthesized samples have been characterized by utilizing various sophisticated physicochemical technique such as X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and energy-dispersive X-ray (EDX) spectroscopy. The synthesized MnO₂/ZIF-8 has been used as counter electrode (CE) for the fabrication of dye-sensitized solar cells (DSSCs). The effect of annealing temperature was studied, and the highest efficiency of 7.2% with a decent open-circuit voltage (V_oc) of 0.77 V was achieved at 200 °C. The obtained efficiency of 7.2% is reasonable in comparison to the platinum (Pt)-based DSSCs (7.4%). This work proposed the construction of Pt-free CE for the development of cost-effective DSSCs with reasonable performance in terms of efficiency.

This work studies gold nanoparticle (AuNP) nucleation and growth mechanism from deep eutectic solvent (DES)-based choline chloride and glycerol (glyceline) onto glassy carbon electrode (GCE) and its application for DNA biosensor. Investigation of the current density transients indicated that the AuNPs were formed by the simultaneous presence of Au diffusion-controlled 3D nucleation and growth and residual water reaction over the Au nuclei growing surfaces. The AuNP structure was characterized by the field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction. AuNPs were used to fabricate electrochemical DNA sensor. The hybridization was monitored by cyclic voltammetry and electrochemical impedance spectroscopy measurement using potassium ferri/ferrocyanide redox probes ({left[Fe{(CN)}_{6}right]}^{3-/4-}) as the indicator probe. Results show that the biosensor exhibited a linear correlation to the logarithm of the target DNA concentration ranged from 1.10⁻¹⁴ M to 1.10⁻⁹ M, and the limit of detection was 1.10⁻¹⁴ M. Furthermore, the findings indicate that the prepared electrode exhibited excellent reproducibility and long-term stability when applied for determining M. tuberculosis samples.

High-energy global requirements have caused a renewed interest in studying and developing new and improved energy storage devices and, precisely, the electrode materials that compose them, which play a fundamental role in determining the device’s performance. Carbon materials are first-class candidates due to their high electrical conductivity, chemical stability, and surface area. Although several carbon materials and their precursors have been studied, melamine sponges stand out for their nitrogen content, allowing them to act as a template and precursor for N-doped, ultralight carbon materials with good mechanical properties and a controlled pore size distribution. This work reports a simple and quick methodology to form ultralight and flexible carbon foam, along with the influence of the pyrolysis temperature on the physicochemical and electrochemical properties of 3D carbonaceous substrates used for energy storage and synthesized from melamine sponges. The substrates exhibit higher 3D porous structure than previously reported materials, with an average pore diameter of 80–90 µm. This morphology, added to the N content, promotes the remarkable electrochemical behavior (MS–950 °C) and cycling stability (MS–1000 °C) of almost 100% of capacitance retention after 10,000 cycles (≈ 60 F/g @1 A/g).

Rapid development of electronic and grid storage technologies based on lithium-ion batteries are leading to tight supply of lithium resources in the future. Extracting lithium from seawater can completely solve the problem of lithium resource shortage. An electro-deposition method based on a lithium superionic conductive solid-state electrolyte, Li_1.5Al_0.5Ge_1.5(PO₄)₃ (LAGP), has been reported to obtain metallic lithium from seawater. However, expensive LAGP increases the cost of lithium extraction, while Li_1.3Al_0.3Ti_1.7(PO₄)₃ (LATP) with relatively lower prices cannot meet the stable requirements. Herein, a low-cost, stable glass–ceramics, Li_1.5Al_0.3Ti_1.7Si_0.2P_2.8O₁₂ (LATSP), has been prepared for lithium extraction from seawater. The LATSP glass–ceramics show good selectivity towards Li⁺ and exhibit a high ionic conductivity of 3.98 × 10⁻⁴ S cm⁻¹ at 22 °C. After soaking in simulated seawater, LATSP showed much better stability than LATP, comparable to LAGP. The resultant LATSP glass–ceramics was successfully employed in a seawater lithium extraction device, with a high lithium extraction Coulombic efficiency of 94.0%. Moreover, the LATSP exhibits an ionic conductivity of 2.80 × 10⁻⁴ S cm⁻¹ and maintains a complete structure after 45 h of lithium extraction. This work presents an effective and practical Li-ion conducting membrane for lithium extraction from seawater.

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The supercapacitive properties of the polythiophene (PTh) and its composites with iron dust synthesized by chemical oxidative polymerization are investigated. The UV–Vis, FTIR, TGA, XRD, SEM, and EDX were used to characterize the composites. Iron (Fe) dust is inserted into PTh matrix as confirmed by FTIR, UV–Vis, EDX, and XRD analysis. The TGA shows that composites have higher thermal stability than pure PTh. The SEM reveals highly porous and packed morphology of the composites as compared to pure PTh. Cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS) show that a 1:1 ratio by mass of PTh and Fe composite displayed greater specific capacitance than pure PTh. The high specific capacitance of the composite material (428.46 F/g at 1 A/g) suggested that the material is suitable for supercapacitor electrode. Cyclic stability is also tested for 1000 cycles at a current density of 1 A/g with excellent retention of 88.89%.

Graphical Abstract

Iron-based Prussian blue analogs (PBAs) are synthesized using a modified coprecipitation approach at different temperatures to study the effect of coprecipitation reaction temperature on structural and electrochemical performance. The experimental results showed that the iron-based PBAs transferred from the cubic structure to the monoclinic phase as the temperature increased from 5 °C to 60 °C, with the former exhibiting rich-in-boundary morphology and the latter showing a well-defined cubic shape. The electrochemical performance of the samples is closely related to the structure: the PBAs with monoclinic structures exhibit a higher charge/discharge specific capacity than those of PBAs with cubic structures. In addition, the samples are further treated at 270 °C, new phases are probed, and the charge/discharge specific capacity for the HT-PB-60 sample is significantly improved by more than 36.15%.

Passivity breakdown mechanism of high-strength 7068 alloy is studied. Breakdown potential varied linearly with log a_Cl^‒, pH, and square root of scan rate in potentiodynamic polarization tests. Mott-Schottky analysis showed that the dominant defect is cation vacancy. Passive layer characteristics like cation vacancy density and defect annihilation rate are determined. Critical cation vacancy density for pitting obtained from point defect model and the theoretical values are somewhat compatible. Chloride concentration of 0.01 M is too dilute to cause severe localized corrosion, whereas beyond 0.5 M, saturation is achieved in terms of breakdown potential and the cation vacancy density.