Highly improved visible-light-induced photocatalytic performance over BiOI/Ag2CO3 heterojunctions

Abstract

A novel BiOI/Ag2CO3 composite was synthesized through the co-precipitation method and well characterized by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, UV-vis diffuse reflectance spectroscopy and photoluminescence spectroscopy. Its photocatalytic activity was evaluated for degrading various pollutants (rhodamine B, methylene blue, methyl orange) and phenol aqueous solution. Experimental results indicated that Ag2CO3 nanoparticles anchored on the BiOI sheet surface promoted the enhanced photocatalytic activity. Moreover, when the mass ratio of BiOI in BiOI/Ag2CO3 composites was 20%, the as-prepared BiOI/Ag2CO3 (20 wt%) composite exhibited the optimal photocatalytic activity for degrading rhodamine B; its rate constant was approximately 6.75 and 4.3 times higher than the separate BiOI and Ag2CO3. The enhanced photocatalytic performance could be attributed to the heterojunctions between BiOI and Ag2CO3. Furthermore, the possible mechanism for photodegradation over the BiOI/Ag2CO3 composite is proposed.