Efficacy of nanoparticles as photocatalyst in leachate treatment

Waste management is critical for creating sustainable and habitable communities, yet many developing countries and cities struggle with it. The inhumane disposal of toxic compounds in water bodies and garbage sites is contaminating the environment. Organic materials such as insecticides, pharmaceuticals waste, dyes and others are employed for a variety of functions, but when discarded in landfills, they constitute a serious health risk. When damp waste is put in a landfill and the site is exposed to rain and runoff, a dark brown liquid known as leachate accumulates at the landfill's bottom, containing some harmful and undesired compounds. This leachate pollutes the soil, groundwater, and surface water when it runs off the land and mixes with it. Landfill leachate is one of the most critical discharges or waste liquids due to its complicated composition, diverse qualities, and strength. In environmental engineering, nanomaterials are emerging as new functional materials capable of enhancing wastewater and leachate treatment. Treatment of leachate has been designated as a high-priority topic for nanotechnology applications. Nano-porous/filter materials, nanofiltration membranes, nano-photocatalysts, and magnetic nano-adsorbent have all been explored in the recent decade as leachate remedies utilizing nanoscience’s. Many researchers agree that these nanoparticles can be used as photocatalysts to remove aqueous contaminants and heavy metals from leachate at a low cost. Nanoparticles have unique quantum effects and a large surface area, making them more effective than bulk materials for leachate clean up. Physical, chemical, and mechanical properties like large SA:V (surface area to volume ratio) all contribute to the generation of oxidising agents at the pollutants surface, assisting in the complete breakdown of complex compounds found in the leachate into simpler compounds, CO 2 , and H 2 O. Because of their small size, nanomaterials as photocatalysts can exhibit a number of unique novel properties that aid in the elimination of organic compound and heavy metals found in leachate in large-scale applications with minimum dosages. The elements that influence nano-photocatalytic activity, as well as the photocatalytic mechanism, are thoroughly examined. By giving a summary of research papers and breakthroughs related to nanoparticle synthesis and their prospective use in leachate remediation, this study aids in the identification of research needs. Graphical abstract