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

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 (E-BG) 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 photo-catalytic 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.(c) 2022 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).