Water organic pollution has become a major issue. A large number of people suffer from the decline in water quality. In addition, polluted water can lead to health problems or excessive deaths. In this regard, an increasingly important method for efficient water treatment is electrocoagulation (EC), the technology that encompasses a small equipment size combined with a simple operation compared to other water treatment methods. The importance of EC is especially accentuated by the recent decarbonization efforts due to the increasing availability of renewable electricity systems. This review provides an overview of the most recent developments in EC technology as it pertains to wastewater treatment. The EC is preferred for organic wastewater treatment over other traditional treatment methods due to its easy setup and low material costs. Moreover, the EC is very powerful in destabilizing organic impurities by charge neutralization and then coagulating to form flocs. In addition, EC has shown high efficiency not only in removing various organic pollutants but also in emerging persistent contaminants, such as microplastics. For these reasons, the EC mechanisms and related functional modalities are reviewed, as well as extensive details are provided on the diversity of the removed contaminants. Overall, this review provides significant new knowledge of interest for environmental chemical researchers in particular and engineers in general on the details of the EC technology for wastewater treatment and water purification.

Urea, a basic chemical compound, holds diverse applications across numerous domains, ranging from agriculture to energy storage. Of particular interest is its role as a hydrogen bond donor (HBD). This specific characteristic has propelled its utilization as an essential component in crafting deep eutectic solvents (DESs) for battery electrolytes. Incorporating urea into DESs presents a promising avenue to address environmental concerns associated with traditional electrolytes, thereby advancing battery technology. Conventional electrolytes, often composed of hazardous and combustible solvents, pose significant environmental risks upon improper disposal potentially contaminating soil and water and threatening both human health and ecosystems. Consequently, there is a pressing need for eco-friendly alternatives capable of upholding high performance and safety standards. DESs, categorized as organic salts resulting from the blending of two or more compounds, have emerged as promising contenders for the next generation of electrolytes. Urea stands out among DES electrolytes by enhancing ion transport, widening the electrochemical window stability (ESW), and prolonging battery cycle life. Further, its non-toxic nature, limited flammability, and elevated thermal stability play pivotal roles in mitigating environmental concerns and safety issues associated with traditional electrolytes. Laboratory testing of urea-based DES electrolytes across various battery systems, including Al-ion, Na-ion, and Zn-ion batteries, has already been demonstrated. This review examines the evolution of urea-based DES electrolytes by elucidating their structure, molecular interaction mechanisms, performance attributes, and preparation methodologies.

Complex inorganic powders based on calcium phosphates have found a plethora of practical applications. Of particular interest are the CaO-P₂O₅ system-based multi-component material powders and granules as the source of major- and micronutrients for the plants. The emerging strategy is to use nano fertilizers based on hydroxyapatite (HAP) for phosphorus and other nutrient delivery. The doping of micronutrients into HAP structure presents an interesting challenge in obtaining specific phase compositions of these calcium phosphates. Various techniques, including mechanochemical synthesis, have been employed to fabricate doped HAP. Mechanochemical synthesis is of particular interest in this review since it presents a relatively simple, scalable, and cost-effective method of calcium phosphate powder processing. The method involves the use of mechanical force to promote chemical reactions and create nanometric powders. This technique has been successfully applied to produce HAP nanoparticles alone, and HAP doped with other elements, such as zinc and magnesium. Nanofertilizers developed through mechanochemical synthesis can offer several advantages over conventional fertilizers. Their nanoscale size allows for rapid absorption and controlled release of nutrients, which leads to improved nutrient uptake efficiency by plants. Furthermore, the tailored properties of HAP-based nano fertilizers, such as controlled porosity and degradation levels, contribute to their effectiveness in providing plant nutrition.

An electrospinning technique was utilized to fabricate a nanofibrous scaffold based on polycaprolactone (PCL) containing co-doped hydroxyapatite (HAP). HAP was modified with different content levels of aluminum/vanadate (Al/V) ions. The final compositions were formulated as xAl/V-HAP@PCL, where x refers to the aluminum concentration. Their compositional, microstructural, morphological, and mechanical behaviors were investigated using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and tensile tests. The cell viability was investigated using the human fibroblast cell line, and this changed from 94.5% to 101.3% as the Al content increased. The contact angle decreased from 100° to 86° with variation of the Al content. The SEM and TEM micrographs exhibit the formation of porous non-oriented fibers with diameters between 40 and 870 nm and particles between 50 and 870 nm in size. XRD showed a variation in crystallinity from 24% to 24.7% for the fibers and from 57.7% to 38.3% for the nanopowder. The tensile tests showed an increase in toughness from 2.34 ± 0.7 to 2.52 ± 0.8 MJ m⁻³. SEM micrographs of cells revealed the proliferation process inside and on the surface of the fibers. These results could be an indicator of a material that can be used for biomedical wound healing applications.