Bismuth Oxide Carbonate Structures Synthesized by Microwave—Assisted Solvothermal Approach and Its Use as Catalyst for the Degradation of Azo Dye in a Solution

Abstract

Because the textile industry wastewater is polluted with azo dyes, and in order to improve a process of wastewater remediation, the synthesized sample was evaluated in the photocatalysis of methylene blue and compared with commercial Bi 2 O 3 and anatase TiO 2 . Structures of bismuth oxide carbonate (Bi 2 O 2 CO 3 ) were successfully synthesized using a solution at 0.03 M concentration of sodium bismuthate as precursor and ethylene glycol as dissolvent by solvothermal microwave-assisted approach. The semiconductor catalyst samples were characterized by X-ray diffraction (XDR), scanning electron microscope (SEM) and Brunauer-Emmett-Teller analysis (BET). The application of the synthesized sample as catalyst, obtained a 68% of degradation. This result is better than the commercial Bi 2 O 3 and close to the anatase TiO 2 degradation. This sample shows a variation in the formula (with the presence of carbonates) but also shows an acceptable degradation percentage according to TiO 2 results, making Bi 2 O 2 CO 3 a possible substitute of TiO 2 .