Synthesis of novel TiO2/CeFeO3 heterojunction using Mugwort (Artemisia vulgaris) leaves extracts with enhanced photocatalytic activity under visible light irradiation

Abstract

TiO₂ is a low-cost and biocompatible material with high oxidizing ability. However, their photocatalytic activity is limited to UV light irradiation. In this research, for the first time, a novel TiO₂/CeFeO₃ heterojunction was synthesized by the green synthesis method using an aqueous fraction of Artemisia vulgaris leaf extracts. TiO₂/CeFeO₃ shows enhanced photocatalytic performance under visible light irradiation. The vibrational, structural, optical, and compositional properties of TiO₂/CeFeO₃ were characterized. The as-prepared TiO₂/CeFeO₃ has spherical-shaped particles and shows a significantly diminished bandgap energy (3.25 eV to 2.75 eV). The photocatalytic performance of TiO₂/CeFeO₃ was investigated to degrade malachite green (MG) with an efficiency of up to 93.53% under its optimum dose. TiO₂/CeFeO₃ shows stable photocatalytic performance until the fourth cycle. The kinetics of the photodegradation of MG followed the pseudo-first-order reaction with a rate constant (k_app) of 2.14×10⁻² min⁻¹. The enhanced photocatalytic activity of TiO₂/CeFeO₃ was attributable to the creation of heterojunction, which suppresses the recombination rate of photogenerated electron-hole validated by the photoluminescence analysis. This work presents an eco-friendly approach to synthesizing novel heterojunction material with enhanced photocatalytic dye degradation.