Water is the most important component on the earth for living organisms. With industrial
development, population increase and climate change, water pollution becomes a critical issue around
the world. Its contamination with different types of pollutants created naturally or due to anthropogenic
activities has become the most concerned global environmental issue. These contaminations destroy
the quality of water and become harmful to living organisms. A number of physical, chemical and biological
techniques have been used for the purification of water, but they suffer in one or the other respect.
The development of nanomaterials and nanotechnology has provided a better path for the purification
of water. Compared to conventional methods using activated carbon, nanomaterials offer a better
and economical approach for water remediation. Different types of nanomaterials acting as nanocatalysts,
nanosorbents, nanostructured catalytic membranes, bioactive nanoparticles, nanomembranes
and nanoparticles provide an alternative and efficient methodology in solving water pollution problems.
However, the major issue with nanomaterials synthesized in a conventional way is their toxicity.
In recent days, a considerable amount of research is being carried out on the synthesis of nanomaterials
using green routes. Nanomaterials synthesized by using the green method are now being used in different
technologies, including water remediation. The remediation of water by using nanomaterials synthesized
by the green method has been reviewed and discussed in this paper.