A New Approach for Photocorrosion In Inhibition of Ag2CO3 Photocatalyst with Highly Visible-Light-Responsive Reactivity

A novel visible-light-responsive photocatalyst Ag2CO3 was prepared by a facile precipitation reaction between NaHCO3 and AgNO3. The as-prepared samples showed relatively high photocatalytic activity toward rhodamine B (RhB) degradation in aqueous solution. The observed photoreactivity on Ag2CO3 was attributed to the synergetic effects of small band gap, great oxidation potential of photogenerated holes, and high separation efficiency of photogenerated electrons and holes. Nevertheless, Ag2CO3 was unstable under visible light due to the photocorrosion resulting from metallic silver formation. The photocorrosion of Ag2CO3 can be efficiently inhibited by adding AgNO3 in the photocatalytic reaction system owing to the lower electrode potential of Ag/AgNO3 than that of Ag/Ag2CO3. Our results shed new light on the photocatalytic activity as well as photocorrosion mechanism of silver-containing compounds and inhibit the method of photocorrosion.