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.

Water pollution is a major concern due to its detrimental effects on the environment and public health. The particular danger of inorganic pollutants arises from their persistent toxicity and inability to biodegrade. Recently, electrocoagulation (EC) has been demonstrated as an alternative sustainable approach to purifying wastewater due to the increasingly strict pollution prevention rules. In particular, EC has been used to remove inorganic pollutants, such as Cr, Zn, Pb, or As. EC has emerged as a sustainable tool for resource recovery of some inorganic pollutants such as N and P that, when recovered, have value as plant nutrients and are critical in a circular economy. These recovered materials can be obtained from diverse agricultural drainage water and recycled as fertilizers. In this work, a state-of-the-art technique is reviewed describing the advances in contaminant removal and nutrient recovery using EC through an in-depth discussion of the factors influencing the contaminant removal process, including operating pH, time, power, and concentration. Furthermore, limitations of the EC technology are reviewed, including the high-power consumption, fast deterioration of the sacrificial electrodes, and the types of contaminants that could not be efficiently removed. Finally, new emerging constructs in EC process optimization parameters are presented.

Hydrogel electrolytes, recognized for their flexibility and superior ionic conductivity, present a viable substitute for liquid electrolytes in energy storage systems. Although Li⁺ and Na⁺ ions have been thoroughly investigated, the intercalation of Cs⁺ ions remains unexamined, despite the significant water solubility of cesium salts. This study designates CsBr as the most effective electrolyte additive owing to its exceptional ionic conductivity (Cs⁺ > K⁺ > Na⁺ > Li⁺ and Br⁻ > Cl⁻ > CH₃COO⁻). A novel hydrogel electrolyte, comprising CsBr, polyacrylamide (PAM), and hyaluronic acid (HA), is developed to tackle the issues of water dehydration. This electrolyte demonstrates high ionic conductivity (10⁴ mS cm⁻¹) and outstanding electrochemical performance in supercapacitors, featuring a specific capacitance of 100 F g⁻¹, approximately 100% coulombic efficiency, and stability over 10 000 cycles. DFT calculations indicate that Cs⁺ generates significant electrostatic interactions, improving charge retention and device efficacy. The results underscore the CsBr@PAM/HA hydrogel as a revolutionary electrolyte for enhanced energy storage, integrating elevated energy and power densities with superior cycling stability.