Synthesis and Applications of Carbon Nano Onions and their Composites for the Remediation of Organic Pollutants from Wastewater

Abstract

Water pollution has emerged as a pressing global issue, posing serious threats to aquatic ecosystems, the food web, human health, and overall environmental integrity. In response, the scientific community is increasingly focused on developing advanced, sustainable technologies for effective water purification. This review highlights the remarkable potential of carbon nano-onions (CNOs) and their composites in wastewater treatment. Owing to their unique structural attributes such as high specific surface area, abundant active sites, and tunable surface functionalities CNO-based materials exhibit outstanding efficiency and selectivity in removing organic pollutants via adsorption and photocatalytic degradation pathways. The review comprehensively examines recent advancements in the synthesis, modification, and application of CNOs for water remediation, offering critical insights into their mechanisms of action, performance metrics, and regeneration capabilities. By consolidating current knowledge and identifying future prospects, this review provides a valuable reference for researchers aiming to harness the multifunctionality of CNOs in addressing the growing challenge of wastewater pollution through environmentally friendly and scalable approaches.