Green synthesis of cerium oxide nanoparticles using Portulaca oleracea Extract: Photocatalytic activities

Abstract

This paper presents a novel method for synthesizing cerium oxide nanoparticles (CeO2 NPs) using Portulaca oleracea extract, focusing on their structural, optical, and photocatalytic properties. CeO2 NPs were prepared through a simple, cost-effective, and environmentally friendly protocol, utilizing the reducing and stabilizing properties of Portulaca oleracea. Structural analysis revealed the formation of cubic CeO2 with an average crystallite size of 16 nm. Optical studies using FTIR and Raman spectroscopy confirmed the characteristic absorption bands of Ce-O and O-Ce-O bonds, while HR-TEM imaging showcased quasi-spherical nanoparticles with sizes ranging from 4 nm to 14 nm. The synthesized CeO2 NPs exhibited significant photocatalytic activity towards the degradation of methylene blue (MB) and methyl orange (MO) under visible light irradiation. The degradation efficiencies achieved were 98 % for MB and 95 % for MO. Kinetic analysis indicated pseudo-first-order degradation kinetics, with observed rate constants of 0.018 min−1 for MO and 0.014 min−1 for MB. Furthermore, CeO2 NPs demonstrated stable and reusable photocatalytic performance over five cycles, highlighting their potential for practical applications in wastewater treatment. Overall, this study presents a promising eco-friendly approach for synthesizing CeO2 NPs with enhanced photocatalytic properties, contributing to the advancement of green nanotechnology for environmental remediation.