Water contamination via heavy metal ions, organic pollutants, and pathogens is a severe threat worldwide, disturbing or threatening both human health and ecosystems even in very small concentrations. Thus, improving water quality is a crucial topic, with both social and economic benefits. In recent years, the use of nanostructured materials to improve water purification systems has been increasingly considered. Nanostructured materials are promising candidates since their nano-scaled nature has important features.