Sonocatalytic Degradation of Methylene Blue with LaMnO3 Supported by Different Surface Area of Graphene

Abstract

The present study compared the sonocatalytic degradation ability of LaMnO3 supported by different surface area of graphene on methylene blue (MB) as a model of the organic pollutant under ultrasonic irradiation. Both sonocatalysts were synthesized by using co-precipitation method and characterized by using X-Ray Diffraction (XRD), Fourier Transform Infrared, and Brunauer-Emmet-Teller (BET) surface area analysis. The orthorhombic structure of LaMnO3 was detected on the composites, while the existence of graphene was also confirmed. The present of graphene in the samples could improve the magnetic properties and surface area of composites as well as the sonocatalytic performance. LaMnO3 supported by different surface area of graphene (SA-1 and SA-2) showed the significant improvement of sonocatalytic activity compared to LaMnO3. LaMnO3/SA-2 composites with the largest surface area showed the highest degradation efficiency. To detect the possible reactive species involved in the degradation of MB, control experiments with introducing scavenger into the solution of MB were carried out. The results indicated that photo-generated hole played an important role in the degradation of MB.