Biogenic synthesized nanocatalysts and their potential for the treatment of toxic pollutants: environmental remediation, a review

Water is the most valuable resource of human civilization and other earth beings. Industrial wastes and dyes are the major threat to these water assets. Untreated industrial wastewater drained into the rivers and oceans results in the water pollution. Therefore, prior to release of these industrial effluents into natural water resources, it is necessity of time to make it environment friendly. For this purpose, various physical and chemical methods have been in practice. But, these methods are more time consuming, expensive and less effective. Consequently, in modern nanotechnology era, use of nanoparticles for the treatment of wastewater has been considered as a better option due to their excellent surface properties which facilitate the catalytic degradation of toxic dyes into environmental benign products. Thus, use of some biological materials for the successful fabrication of metal nanoparticles as well as metal oxides nanoparticles and their use as catalyst for various organic reactions are gaining attention nowadays because of their eco-friendliness nature and easy availability. Here, this review article provides the updated role played by phytocompounds present in plants extract toward the preparation of different metal and metal oxide NPs along with their use as catalyst for photo- and chemical degradation of different toxic pollutants present in water sources. Different conditions to optimize the activity of nanomaterials in cleaning water process have also been reviewed critically. Future prospective of green-synthesized nanomaterials role as water cleaner has also been enlighten here in detail.