Synthesis, characterization and properties of sulfate-modified silver carbonate with enhanced visible light photocatalytic performance

Sulfate-modified AgCO was successfully synthesized a simple precipitation method. Its visible light photocatalytic performance against the removal of Orange G was found to be significantly enhanced in comparison with the one of pure AgCO. While SO-AgCO ensured a removal efficiency of 100% of OG within 30 min, the unmodified AgCO exhibited a degradation threshold at hardly 60%. Likewise, the degradation rate constant in the presence of SO-AgCO photocatalyst was assessed to be twice that determined upon the involvement of pristine AgCO. Furthermore, Total Organic Carbon (TOC) measurements evidenced the occurrence of a quasi-total mineralization of the dye pollutant upon the use of SO-AgCO photocatalyst. Scavenger experiments highlighted the dominant role of photo-induced h along with ˙O ozonide radicals in the OG photocatalytic oxidation mechanism. Reuse cycles revealed that the modification by SO is a promising route to improve the stability of silver carbonate against photocorrosion. All these improvements could be ascribed to electronic transfer from the upper SO HOMO to the lower AgCO conduction band.