Sustainable Synthesis of Zirconium Dioxide (ZrO2) Nanoparticles Utilizing Asphodelus fistulosus Extract for Congo Red Degradation

This research presents a green approach to synthesizing zirconium oxide (ZrO2) nanoparticles using an Asphodelus fistulosus plant extract as a reducing and stabilizing agent. The synthesized ZrO2 nanoparticles were characterized using various advanced techniques. The XRD pattern provides different forms of ZrO2, like tetragonal and cubic forms, and the results confirmed the successful formation of crystalline ZrO2 nanoparticles with a definite morphology. The XPS data exhibit that the bioactive chemicals present in the extract, including polyphenols, flavonoids, and reducing sugars, perform the functions of reducing and capping agents. Additionally, CR dye molecules may create hydrogen bonds with these surface moieties, which are approved by FTIR. These interactions may assist in aligning dye molecules with catalytically active regions on ZrO2 surfaces and may interact with photogenerated species. The catalytic activity of the synthesized ZrO2 nanoparticles was evaluated for the degradation of Congo red dye under ultraviolet irradiation. The nanoparticles exhibited excellent photocatalytic activity, degrading a significant amount of the dye within a short period. Various parameters were investigated to optimize the photodegradation process, including irradiation time, catalyst dosage, pH, and initial dye concentration. The optimal conditions were determined to be a pH of 7, a catalyst loading of 20 mg/L, and an irradiation time of 75 min, resulting in a remarkable ≈92% degradation efficiency. This green synthesis method offers a sustainable and eco-friendly alternative to conventional chemical methods for producing ZrO2 nanoparticles, which have potential applications in environmental remediation.