This chapter focuses on green, ecological, sustainable, and low-cost methods of nanostructures composed of metal oxides and combinations of metals synthesis, surface doping, and stable incorporation into membranes and fibrous materials. In particular, for the synthesis of metal oxide nanoparticles, ecological procedures using plant extracts (shrubs, herbs, and trees), microorganisms (bacteria, fungi, and algae), and biological derivatives (proteins, peptides, and starches) are used for necessary redox reactions. Such green nanoparticles have a substantial impact on environmentally friendly chemistry since they have the potential to be used in a variety of industries, such as agriculture, electronics, and medicine. Green nanoparticles can also lessen the environmental impact of traditional methods of nanoparticle production, helping to advance a more ecologically friendly and sustainable approach to materials science. Green synthesis of nanomaterials can be incorporated with the in-situ immobilization on membranes and fabrics and appropriately activating fibrous surfaces to prepare eco-friendly and sustainable materials that represent advanced properties.