Synthesis and characterization of Cu2O–modified Bi2O3 nanospheres with enhanced visible light photocatalytic activity

In this work, a series of Cu2O–modified Bi2O3 nanospheres with perfect visible-light catalytic activity were successfully synthesized via the two-step method. The obtained products were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) surface area, UV–visible diffuse reflectance spectroscopy (UV–vis DRS), and X-ray photoelectron spectroscopy (XPS). In the catalysts of Cu2O–modified Bi2O3 nanospheres, Cu2O was dispersed on the surface of Bi2O3 nanospheres. All of Cu2O–modified Bi2O3 nanospheres showed uniformly nanospheres with the size of 80–150 nm, and exhibited enhanced photocatalytic activity in the degradation of Rhodamine B. The higher BET surface area, the band gap narrowing, and the interfacial charge transfer effect were considered to cause the excellent photocatalysis of Cu2O loading Bi2O3 samples. Furthermore, the possible photocatalysis mechanism was proposed.