Hydrothermal synthesis of Ca3Bi8O15 rods and their visible light photocatalytic properties

High efficient visible light Ca3Bi8O15 photocatalysts were synthesized by a hydrothermal method. Characterized by X-ray diffractometer, transmission electron microscopy, and the UV–vis diffuse reflectance spectroscopy, the results showed that the novel Ca3Bi8O15 rods can utilize the sunlight efficiently with the small band-gap. Using methyl orange (MO) as a model organic pollutant, the photocatalysts exhibited good photocatalytic activity, with the photodegradation conversion ratio of MO being up to 90% after 2 h of visible light (420 nm < λ < 800 nm) irradiation. Furthermore, they also showed good photocatalytic activities in the degradation of rhodamine B and p-chlorophenol. Through the investigation of the degraded mechanism, the main active species played important roles in the degradation process were holes, O2·− and OH.