Greener Aspects of Nanoparticle Synthesis for Water Remediation: Challenges and Future Perspective

Continued industrialization, urbanization and ecological destruction have caused significant environmental problems, particularly increased water pollution. Introducing harmful organic and inorganic effluents into watercourses has limited the supply and accessibility of safe and affordable drinking water. There is an urgent need to find green and sustainable abatement solutions for water remediation, many based on nanoparticles. The primary objective of this review is to explore and have a comprehensive discussion on the present trends, challenges and prospects for the green synthesis of nanoparticles for wastewater remediation. The connection between green chemistry and nanoparticles synthesis is articulated with many examples exploring the use of renewable or biobased resources. Energy-efficient processes (microwaves, ultrasound and laser ablation) and the use of alternative solvents (supercritical carbon dioxide, ionic liquids and biobased solvents) are explored. The review aims to make the readers discern the mechanistic insights towards the working of various green processes. Conclusively, the adoption of green nanotechnology has the potential to veritably addresses the global water shortage issue under the domain of environmental sustainability.