Synthesis and characterization of Bi₂O₃and Ag-Bi₂O₃and evaluation of their photocatalytic activities towards photodegradation of crystal violet dye

The development of visible light effective photocatalysts for photodegradation of organic pollutants is a hot topic in current wastewater treatment research. In this study, visible light-responsive photocatalysts, the Ag-Bi2O3, are reported as active photocatalysts for photodegradation of crystal violet dye, a model pollutant. The Ag-Bi2O3 photocatalysts loaded with 5, 10, and 15% Ag were prepared and described with XRD, SEM, and EDX. The characterization confirmed the formation of material with β-Bi2O3 as the main constituent in the crystalline phase. The results of photocatalytic degradation experiments showed that Ag-Bi2O3 is more active for photodegradation of crystal violet dye than the pristine Bi2O3. Furthermore, the Ag-Bi2O3 loaded with 5% Ag showed the highest catalytic activity among the Ag-Bi2O3 loaded with 5%, 10%, and 15% Ag content. The analysis of photodegradation experiments showed that about 52 to 92, 76, and 57% of 100 mg l-1 of crystal violet dye degraded with Bi2O3, and Ag-Bi2O3 loaded with 5% Ag, 10% Ag, and 15% Ag, respectively. The reaction kinetics is described according to the Langmuir-Hinshelwood mechanism.