Novel synthesis and enhanced catalytic performance of stable nano-scale Fe~0, Ag~0 and ZnO nanoparticles: photo-degradation under mercury lamp

摘要

This study was planned to synthesize the Fe-0, Ag-0 and ZnO nanoparticles (NPs) and measure their catalytic potential to degrade the industrial pollutants into non-pollutant materials. Iron and silver NPs have been obtained through leaf extract of Azadirachta indica and ZnO NP has been synthesized over leaf extract of Corriandrum sativum as single step, simple, cheap and eco-friendly green synthesis. The synthesized NPs were confirmed by UV-visible spectroscopy and further characterized by scanning electron microscopy (SEM), energy dispersive X-Ray spectroscopy (EDS), fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The photocatalytical potential of the synthesized NPs was measured as photodegration of methyl orange (MO) azodye as model organic compound under high pressure mecury lamp of 125 W and 500 W. The photodegradation was 24%, 30% and 51% after 4.5 h at 125 W and 56%, 60% and 83% after 4 h at 500 W for silver, iron and zinc oxide NPs, respectively. Catalytic potential of ZnO was better with 0.47 and 0.087 absorbances as compared to silver and iron NPs under both 125 W and 500 W, respectively. The potential of ZnO NPs was much better at 500 W than 125 W. The optimum degradation of methyl orange with ZnO NPs was observed at 0.6 g/L, and acidic pH (=3) further enhance and hasty the degradation. Consequently, 98.5% MO was degraded at 3 pH and 500 W. The plausible mechanism of photodegradationwas also discussed.