Biosynthesis of Ag NPs/ Crataegus kernel substrate as a green and retrievable Catalyst for Wastewater treatment

Nitrophenol compounds are one of the most harmful pollutants in wastewaters widely used in various industries so, removal of these harmful pollutants is essential. In this research, the extract of the plant of Lotus corniculatus L. was used to green synthesis of Ag nanoparticles (NPs) supported on Crataegus kernel as an environmentally benign support. Ag NPs/ Crataegus kernel as an effective catalyst was prepared through reduction of Ag+ ions using Lotus corniculatus L. extract as the reducing and capping agent and Ag NPs immobilization on Crataegus kernel surface in the absence of any stabilizer or surfactant. According to FT-IR analysis, the hydroxyl groups of phenolics in Lotus corniculatus L. extract as bioreductant agents are directly responsible for the reduction of Ag+ ions and formation of Ag NPs. The as-prepared catalyst was characterized by Fourier transform infrared (FT-IR) and Uv-Vis spectroscopy, field emission scanning electron microscopy (FESEM) equipped with an energy dispersive X-ray spectroscopy (EDS), Elemental mapping and, X-ray diffraction analysis (XRD). The synthesized catalyst was used in the reduction of 4-nitrophenol (4-NP) at room temperature. The Ag NPs/ Crataegus kernel showed excellent catalytic activity in the reduction of these organic dyes. In addition, it was found that Ag NPs/ Crataegus kernel can be recovered and reused several times without significant loss of catalytic activity.