Preparation of Ca_0.1Cu₀.₉₀Bi₂O₄ heterojunction with improved visible light photocatalytic performance of congo red: Kinetics and degradation mechanisms

Progression in nano technology enormously influence on the synthesis of highly proficient photo materials and investigate their applications in diverse fields. The CuBi₂O₄ and Ca_0.05Cu_0.95Bi₂O₄, Ca_0.1Cu_0.90Bi₂O_4, and Ca_0.15Cu_0.95Bi₂O₄ microspheres were prepared by one-step simple hydrothermal method. All the synthesized nanostructures were comprehensively characterized by different spectroscopic techniques. The composite was used in treating water contaminated by azo dye Congo red under visible light irradiation. The pure CuBi₂O₄ showed 46% of congo red degradation within 70 min of irradiation, while Ca_0.1Cu_0.95Bi₂O₄ showed 82% of photo degradation within 70 min of irradiation. Among all the synthesized materials the Ca_0.1Cu_0.95Bi₂O₄ showed best efficiency with high degradation constant using lest time. Meanwhile, the photocatalytic study of dye was studied under six operational parameters such as effect of dosage, initial concentration, pH, H₂O₂ and inorganic salts. The maximum photocatalytic activity was obtained 94% within 60 min of irradiation in the presence of 0.6 mL of H₂O₂. The obvious enhanced photocatalytic efficiency of Ca_0.1Cu_0.95Bi₂O₄ should be attributed to uniform dispersion and floating behaviour of the well-designed photocatalyst. As a result, the Ca_0.1Cu_0.95Bi₂O₄ photocatalyst with hierarchical porous structure would open an avenue for the treatment of wastewater.