Synthesis and characterization of Fe2SiO4/Fe2O3/g-C3N4 ternary heterojunction photocatalyst with enhanced photocatalytic activity under visible light

Abstract

Ultrasonic-assisted co-precipitation is used for the first time to prepare Z-scheme Fe2SiO4/Fe2O3/g-C3N4 ternary heterojunction photocatalysts. Their morphology, crystal structure, specific surface area, optical properties, composition, and photocatalytic behavior have been thoroughly examined. When compared to single-component and binary Fe2SiO4/Fe2O3 heterojunction photocatalysts, ternary Fe2SiO4/Fe2O3/g-C3N4 heterojunction photocatalysts exhibit the most profitable performance for degradation of erythrosine under simulated light. It is likely that this is due to the high rate of separation migration of photoexcited charge carriers, the formation of Z-scheme heterojunction, and the specific surface area. Based on the results of active species trapping experiments, a possible Z-scheme mechanism could explain the significantly reduced photocatalytic rate of ternary heterojunction photocatalysts. It has been demonstrated that superoxide radicals play a significant role in the photodegradation process. A kinetic analysis revealed that the higher efficiency (97.9%) was associated with a higher rate constant (k = 0.0345 min‒1). A Fe2SiO4/Fe2O3/g-C3N4 nanocomposite is an excellent choice for large-scale applications because of its exceptional stability and recyclability.