Chemical-Bonds-Conjugated Ag2SO3/NaNbO3 Hybrids as Efficient Photocatalysts: In-Situ Fabrication, Characterization and Degradation of Rhodamine B and Methyl Orange

The Ag 2 SO 3 /NaNbO 3 hybrids have been fabricated via a facile method at room temperature. Several methods such as X-ray diffraction, UV-Vis diffuse reflectance spectroscopy, scanning electron microscopy, electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy were used to characterize the samples. Moreover, the photocatalytic activity of the samples was assessed by degradation of rhodamine B and methyl orange under the visible light illumination. Experimental results indicated the photocatalytic degradation efficiency of the as-fabricated hybrids was first increased and then decreased with increasing the dosage of NaNbO 3 . When the molar ratio of Ag 2 SO 3 to NaNbO 3 was 1:0.7, the as-fabricated composites had the best photodegradation efficiency of 96.4% in 30 min for rhodamine B and 97.1% in 60 min for methyl orange, respectively. These were obviously higher than that of pure samples. Furthermore, Ag 2 SO 3 was conjugated with NaNbO 3 via chemical-bonds rather than physical contact. In addition, the possible photocatalytic degradation mechanism was also provided and the main roles during the process of photocatalytic degradation were played by holes.