Biosynthesis of ZrO 2 nanoparticles from Ficus benghalensis leaf extract for photocatalytic activity

The biosynthesis of metal oxide nanoparticles (NPs) using plant extract is green, rapid, attractive and cost-effective approach. In the present study, we are reporting biosynthesis of ZrO2 NPs as an efficient photocatalyst by using Ficus benghalensis (F.B.) leaf extract as a capping agent for the first time. To determine its optical, structural and morphological properties, the obtained ZrO2 NPs were characterized by using UV–Vis, DRS, XRD, FT-IR, HR-TEM, FT-Raman and BET-surface area. XRD pattern confirms that biosynthesized ZrO2 NPs are crystalline in nature with monoclinic and tetragonal structure. TEM images show that the obtained ZrO2 NPs has spherical morphology with 15 nm in size which is good agreement with XRD results. A decrease in the band gap of bulk ZrO2 from 5.3 to 4.9 eV is observed due to the quantum size effect. The as-synthesized ZrO2 NPs have high specific surface area of 88 m2/g was obtained by BET analysis. The photocatalytic efficiency of ZrO2 NPs is evaluated for the photodegradation of methylene blue and methyl orange dyes as the target pollutants under UV light irradiation. The different parameters like catalyst loading amount and pH have also been studied. It is observed that photodegradation of methylene blue and methyl orange up to 91 and 69% within 240 min by using ZrO2 catalyst. Moreover, this green synthesis process provides a valuable alternative to orthodox multistep processes for the preparation of ZrO2 NPs.