Solar Degradation of Sulfamethazine Using rGO/Bi Composite Photocatalysts Fernández Perales, M. Rozalen, Marisa Sánchez Polo, Manuel Rivera Utrilla, José rGO/Bi composites Photocatalysts Microwaves Solar radiation Sulfamethazine This work was supported by the Spanish Ministry of Economy, Industry and Competitiveness and by FEDER (CTQ2016-80978-C2−1-R), and the authors thank to Dr. Isabel Guerra Tschuschke for the technical advice during the VP-SEM study at the CIC-UGR. Heterogeneous photocatalysts for water decontamination were obtained by the optimized synthesis of bismuth-functionalized reduced graphene oxide (rGO/Bi) using the Hummer method and microwave treatment. Sulfamethazine (SMZ) was used as model pollutant to evaluate the photocatalytic efficacy. Photocatalysts were characterized by VP-SEM, HRTEM, XDR, XPS, RAMAN, and FTIR analyses, which confirmed the effective reduction of GO to rGO and the presence of bismuth as a crystalline phase of Bi2O3 polydispersed on the surface. Their performance was influenced by the rGO/Bi ratio, microwave temperature, and treatment time. The as-obtained 5%rGO/Bi composite had the highest photocatalytic activity for SMZ degradation under visible light irradiation (λ > 400 nm), achieving 100% degradation after only 2 h of treatment. The degradation yield decreased with higher percentages of rGO. Accordingly, the rGO/Bi catalysts efficiently removed SMZ, showing a high photocatalytic activity, and remained unchanged after three treatment cycles; furthermore, cytotoxicity tests demonstrated the nontoxicity of the aqueous medium after SMZ degradation. These findings support the potential value of these novel composites as photocatalysts to selectively remove pollutants in water treatment plants. 2020-07-28T11:55:04Z 2020-07-28T11:55:04Z 2020-05 info:eu-repo/semantics/article Fernández-Perales, M., Rozalen, M., Sánchez-Polo, M., Rivera-Utrilla, J., López-Ramón, M. V., & Álvarez, M. A. (2020). Solar Degradation of Sulfamethazine Using rGO/Bi Composite Photocatalysts. Catalysts, 10(5), 573. [DOI: 10.3390/catal10050573] http://hdl.handle.net/10481/63173 10.3390/catal10050573 eng http://creativecommons.org/licenses/by/3.0/es/ info:eu-repo/semantics/openAccess Atribución 3.0 España MDPI