Advances in self-cleaning membranes for effective water and wastewater treatment

The growing pollution of environmental resources caused by industrial and human activities needs the introducing of innovative purification techniques. Among the advanced water treatment methods, membrane-based processes have emerged as an efficient option. However, membrane fouling is one of the main weak points decreasing the process efficiency and increasing operational expenses. Self-cleaning membranes are one of the potential solutions by using surface modifications with different materials and processes. In this paper, we have reviewed various self-cleaning mechanisms, including the passive approaches (e.g. hydrophilic, hydrophobic, piezoelectric and amphiphilic surfaces), as well as active techniques. We explained the catalytic self-cleaning membranes such as photocatalytic, Fenton-assisted and catalytic activation-assisted self-cleaning membranes. The integration of nature-inspired designs, enzyme-based biocatalytic solutions, and advanced oxidation processes it is possible to enhance the efficiency and durability of membranes, and adaptability to diverse water sources while reducing chemical usage, and operational costs. Also, we have summarized the recent studies on the mechanisms of thermal, pH, and electrochemical-responsive self-cleaning membranes for altering hydrophilicity or hydrophobicity to release foulants which improves treatment processes, minimizes chemical dependencies, and extends membrane lifespans. In conclusion, self-cleaning membranes represent a promising pathway toward sustainable and cost-effective water and wastewater treatment.