Photocatalytic Performance of Ag and CuBiS2 Nanoparticle-Coated SiO2@TiO2 Composite Sphere under Visible and Ultraviolet Light Irradiation for Azo Dye Degradation with the Assistance of Numerous Nano p-n Diodes

Ag and CuBiS2 nanoparticle-coated SiO2 sphere@nano TiO2 coating (SiO2@TiO2) composite catalyst (abbreviated as SiO2/TiO2/CuBiS2/Ag) has been successfully synthesized and characterized as well as tested for photocatalysis of Acid Black 1 (AB 1) dye under visible and ultraviolet (UV) light irradiation. These as-prepared composite spheres show photocatalytic activities under visible and ultraviolet light irradiation. This work is the first report of CuBiS2 semiconductor nanoparticles used as a material for photodegradation. The data showed that the SiO2/TiO2/CuBiS2/Ag composite particles completely degraded 50 mL of 10 ppm AB 1 dye solution in only 5 min under UV light irradiation and 100 mL of 5 ppm AB 1 dye solution in 30 min under visible light irradiation. The good photocatalysis of our composite spheres is attributed to the establishment of a good p-n heterojunction interface between the p-type CuBiS2 and n-type TiO2 semiconductors with the assistance of Ag nanopartides.