Optimization strategies and emerging application of functionalized 3D-printed materials in water treatment: A review

Access to clean water is a fundamental problem that has been emphasized by the United Nations and World Health Organization. Water is one of the vital necessities for humans to stay alive and prevent disease. However, due to the increasing world population and climate change, it is predicted water resources will be stressed and limited due to poor quality. Various water treatment processes have been developed based on the presence of contaminants in water to solve the urgent issue. Due to the outstanding ability to meet the demands of commercial applications, the newest methods of combining additive manufacturing (AM) and surface functionalization have attracted a lot of attention in recent years. With the rapid advancement of this field, more advanced, flexible, and efficient surface functionalization strategies for additively manufactured materials have been discussed. The strategy and methods, including etching, deposition processing, surface grafting, and biofilm growth, are summarized concisely, alongside with the surface enhancement property such as antifouling, mechanical and chemical stability and other unique features. In this work, recent advances in functionalized 3D-printed materials used in various water research as mesh, membrane, photocatalyst, scaffold and biocarrier are reviewed. Furthermore, the fundamental issue associated with 3D functional materials is assessed along with the proposed process optimization strategies. Lastly, the challenges and future perspectives of functionalized 3D-printed materials are discussed to develop a novel and versatile approach for functions in the water treatment system.