Journal of Solid State Electrochemistry最新文献

A brief review of micro/nano fabrication procedures based on electroplating and anodic oxidation processes is accenting the overlap with traditional electrochemical surface finishing, and the role of electrochemical tools to control and monitor technological processes. Consideration is limited to fabrication of ordered structures and their fragments being of interest for research in physics, and also for corresponding devices. The review also addresses the progress in electrochemical fabrication of functional materials (superconducting, magnetic, optical) utilized in such devices, and nanotechnological applications of electrochemical intercalation. The review can be considered as a guide to bibliography on electrochemical micro/nano fabrication.

Electrochemical micro-milling (ECMM) is promising in machining micro-parts with the increasing demand for precise and small parts in the industrial field. However, the machining accuracy is always a problem due to the over-corrosion in ECMM. Considering the machining accuracy and the material removal rate, ultrasonic-assisted ECMM using a side wall insulated cathode was proposed in this study. Ultrasonic vibration promotes the discharge of the byproducts and enhances the renewal of electrolyte in the interelectrode and the coating on the cathode, reducing the overcut of the workpiece material. Microgrooves and 3D structures are processed layer by layer, and the cross-sectional profiles and surface roughness are measured by a 3D laser scanning microscope. Firstly, the influences of individual parameters on machining performances were analyzed, and their optimal values were obtained. Then, different milling schemes concerning the layered cathode feeding depth, milling trajectory, and offset were designed to investigate and discover the performances of machined 3D microstructures. Finally, a semi-spherical workpiece with a diameter of 600 µm, surface roughness of 223 nm, a cantilever with a width of 101.6 µm, and an aspect ratio of 8.43 was successfully processed based on the optimized parameters.

In this study, we introduce a simple, cost-effective, and scalable method for producing magnetic nanoparticles. We demonstrate the potentiostatic electrodeposition of Permalloy (NiFe) nanoparticles onto an alumina sacrificial layer over aluminum, achieving high reproducibility and the formation of nanoparticles with a hemispherical morphology, approximately 150 nm in size. A novel approach for detaching the nanoparticles from the substrate and dispersing them into solution is also developed. The interest in these small-scale hemispherical nanoparticles stems from their magnetic vortex configuration, which exhibits low remanence and inhibits the formation of larger clusters in solution due to dipolar interactions. This behavior, attributed to their intrinsic curvature, is particularly relevant for applications in effective magnetohyperthermia therapy for cancer, with possibility of nanoparticles phagocytosis due to it small sizes. The magnetic vortex configuration was characterized for both the nanoparticles on the substrate and in solution using magnetic susceptibility measurements and further confirmed through micromagnetic simulations with the open-source code Mumax( ^{3}).

Scanning electrochemical probe techniques are powerful methods for electrochemical patterning in micro and nanoscale. This review covers the electrochemical patterning in both 2D and 3D through selected examples. These include generation-collection and direct mode scanning electrochemical microscopy (SECM), scanning electrochemical cell microscopy (SECCM) and scanning gel electrochemical microscopy (SGECM). The vertical resolution in SECM and the lateral resolution of SECCM patterning have both achieved < 100 nm. The direct mode SECM and SECCM are in theory applicable to all electrodeposition reactions in terms of chemistry, which is a great advantage over competing techniques such as inkjet printing and lithography. The main issues of the techniques, i.e. the control and the speed, are discussed in a critical way with constructive prospects proposed.

Electrochemical oxidation of aluminium in acidic electrolyte solutions, also known as anodizing, is a widely used process for the finishing of pure aluminium and its alloys. The resulting anodic aluminium oxide (AAO) porous films play a significant role in modern science and technology. One of the most exciting features of AAO is the self-organization of pores into two-dimensional hexagonal patterns under specific anodizing conditions. The combination of a hexagonal arrangement of pores and precise control over pore diameter, interpore distance, and film thickness gives rise to a wide range of potential applications from decorative coatings to quantum technologies. This review discusses the kinetic approach to the guided search for anodizing conditions that lead to the formation of highly ordered porous structures, as well as recent data on how the crystallographic orientation of the aluminium substrate affects the growth rate and structure of AAO.

Monocrotophos (MCP)—a toxic organophosphorus (OP) insecticide—has been widely used in the agricultural field to protect crops from weeds, vectors, insects, etc. Among the different OP pesticides—methyl parathion, dichlofenthion, paraoxon, etc.—monocrotophos is the one which is frequently used by farmers because of its high insecticidal prevention activity. Due to its excellent solubility in water, the residues of MCP have a high chance of entering into the human food cycle which sequentially causes acute poisoning and various health issues. To address it, an effective detection system should be implemented that has the capability of detecting MCP at very low concentrations. Herein, bismuth ferrite particles with varied morphology and surface properties are synthesized using sol–gel and hydrothermal methods, and their sensing properties are effectively compared. Structural, morphological, and surface area measurements are carried out by TG/DTA, XRD, FTIR, HRSEM, and BET, respectively. Consequently, fluorine-doped tin oxide (FTO)-modified bismuth ferrite (BFO) electrodes were used for electrochemical detection of monocrotophos. Relatively, bismuth ferrite xerogel powders exhibit good stability for up to 3 weeks with a limit of detection (LOD) of 0.638 µM. From the laboratory study, it can be understood that the synthesis procedure plays a crucial role in the electrochemical detection of pesticides.

Graphical abstract

The main aim of this study was to investigate the effectiveness of the sonocatalytic systems for the catalytic treatment of Olive Mill Wastewater (OMW) effluent streams. For this purpose, four different types of activated carbon-supported catalysts (TiO₂/AC, V₂O₅/TiO₂/AC, WO₃/TiO₂/AC, and V₂O₅/WO₃/TiO₂/AC) were synthesized by sol–gel method. The sonocatalysts were characterized by using TEM, SEM, XRD characterization techniques, and BET analyses. The performance of these novel catalytic systems was investigated by conducting experiments to remove various types of polluting components from OMW such as color, lignin, and chemical oxygen demand (COD). Preliminary experiments were conducted to evaluate the effects of various parameters such as reaction time, catalyst type, amount (as solid/liquid ratio), ultrasound amplitude, and initial pH values for process optimization. In the preliminary studies, it has been observed that there was no change in the percentage removal of the abovementioned polluting components. In the second set of experiments, hydrogen peroxide (H₂O₂) was used as the oxidizing agent. The results showed that the V₂O₅/TiO₂/AC catalyst was much better than the remaining catalysts in the removal of color, lignin, and COD from OMW effluent streams. In addition, when this method was used, it was observed that lignin was removed significantly (60%), but an increase in phenol concentration was observed (40%). It was observed that high efficiency was obtained under experimental conditions of V₂O₅/TiO₂/AC catalyst, catalyst amount: 1.0 gL⁻¹, time: 90 min, 1 mLL⁻¹ H₂O₂, 60% amplitude, and natural pH. In addition, it was observed that the removal was higher as the amplitude ratio increased and pH values were lower. It can be said that the sonocatalytic process may be more effective at the beginning, and the efficiency increase may be higher when integrated with the other processes.