Study of catalytic activity of G-SrO nanoparticles for degradation of cationic and anionic dye and comparative study photocatalytic and electro & photo-electrocatalytic of anionic dye degradation

Abstract

Cationic dye (methylene blue) and anionic dye (carmine) degradation were demonstrated by SrO and G-SrO NPs. Furthermore, the carmine dye was degraded using two promising technologies: photocatalysis and electro& photo-electrocatalytic oxidation. Analyses of the synthesized photocatalysts were carried out utilizing optical techniques such as Fourier transforms infrared (FTIR), X-ray diffraction (XRD), UV–visible absorption, and Scanning Electron Microscopy (SEM). The FTIR results showed that no band for graphene appeared. The XRD data revealed that the nanocomposite has a cubic structure typical of SrO, which is highly crystalline. The energy band gap (EBG) decreases from 6 eV to 3.87 eV for SrO and 0.25 G-SrO, respectively. SEM images showed that incorporating graphene into SrO might enhance the surface area.For photocatalytic applications, the results revealed that the 0.25G-SrO catalyst achieved 99.5% degradation of MB dye and kinetic degradation rates of 0.04718 min−1 within 70min by photocatalysis under UV light irradiation. In comparison, 0.1G-SrO catalyst reached 79.03% degradation of carmine and kinetic degradation rates of 0.01182 min−1 within 125 min. The carmine dye was completely degraded with 8 min and 6 min irradiation time by electro and photo-electro catalytic. According to this research, SrO's photocatalytic activity was improved by incorporating graphene under UV light; besides comparing photocatalysis and electro &photo-electro catalytic processes to verify which technique is best for treating carmine in effluents.