Photocatalytic activity of iron oxide nanoparticles synthesized by different plant extracts for the degradation of diazo dyes Evans blue and Congo red

This work describes the use of XRD, SEM, and infrared spectroscopy in the evaluation of iron oxide nanoparticles as produced from three distinct plant extracts. The efficacy of the nanoparticles in terms of dye sorption was assessed using Congo Red (CR) and Evans Blue (EB) dyes. The research revealed that the synthesis method influences the properties of nanoparticles, which leads to different levels of effectiveness when it comes to sorption. The proposed sorption mechanism was founded on several characterization studies. Moreover, it was discovered that sorption might occur due to pores or binding groups rather than only an electrostatic connection. The results show that the nanoparticles’ sorption effectiveness is heavily pH dependent. The produced nanoparticles showed potential for application in water treatment technologies due to the synthetic technique relative ease and the possibility of a low-cost catalyst.