A Literature Review of Cerium-Based Photocatalytic Nanocomposite Membranes for the Elimination of Persistent Organic Pollutants in Wastewater

Persistent organic pollutants (POPs) in wastewater pose significant environmental and health risks due to their toxicity, persistence, and bioaccumulation. Conventional treatment methods often struggle to effectively remove these pollutants, necessitating the development of advanced technologies. Cerium-based photocatalytic nanocomposite membranes have emerged as a promising solution, combining the benefits of physical separation and photocatalytic degradation. This review provides a comprehensive analysis of the advancements in cerium-based photocatalytic membranes for wastewater treatment, focusing on their composition, synthesis methods, photocatalytic properties, and applications. The incorporation of cerium dioxide (CeO2) nanoparticles into membranes enhances hydrophilicity, porosity, and separation performance, with optimal loading levels of 2–3 wt.% demonstrating significant improvements in mechanical properties and water flux. The photocatalytic efficacy of these membranes is influenced by factors such as nanoparticle size, morphology, surface area, and the incorporation of additional materials like graphene oxide or metal oxides. Cerium-based photocatalytic membranes have achieved pollutant removal efficiencies exceeding 95% for a wide range of contaminants, including dyes, antibiotics, oils, and heavy metals. However, challenges such as the wide bandgap of CeO2, scalability issues, and long-term stability concerns need to be addressed for successful industrial implementation. Future perspectives highlight the potential of hybrid nanocomposites, metal and non-metal doping, morphology control, and advanced heterojunction construction to enhance the performance and sustainability of cerium-based photocatalytic membranes for wastewater treatment applications.