Green synthesized N-CQDs@NiO nanocomposites for efficient photocatalytic degradation of organic pollutants from water

The alarming increase in environmental contamination caused by the untreated release of hazardous phenolic compounds such as 3-Aminophenol (3-AP) and Safranin-O (SO) dye has become a serious global issue. Traditional cleanup methods have limitations, so we must decline practical approaches that do not harm the environment. The purpose of this research was to develop a new catalytic system for advanced oxidation processes (AOPs) by combining nitrogen-doped carbon quantum dots (N-CQDs) with nickel oxide (NiO) nanocomposites. Citrus limetta leaves were utilized to create N-CQDs, which were then combined with NiO nanoparticles via green tea extract. A thorough investigation revealed that N-CQDs were successfully added to the NiO matrix, increasing the nanocomposite's structural stability and photocatalytic properties. Sunlight-based tests showed that N-CQDs@NiO nanocomposites were better at breaking down chemicals than NiO nanoparticles alone, with 99 % efficiency for 3-AP and 98 % efficiency for SO. The higher efficiency was due to N-CQDs’ better ability to adsorb substances, keep particles from sticking together, and separate charges effectively, which made it easier for reactive species like superoxide anions and hydroxyl radicals to form. This work shows that N-CQDs@NiO nanocomposites could clean up the environment and provide a long-term way to break down persistent organic pollutants in wastewater. In the future, researchers will try to improve the process of making these nanocomposites and find ways to use them in real wastewater treatment systems.