Preparation of Ag2SO3 sub-microparticles with high visible-light photocatalytic activity

A visible-light sensitive Ag₂SO₃ semiconductor photocatalyst with size of ca. 500 nm was prepared by a simple precipitation method. This photocatalyst exhibits high-efficiency degradation ability for typical three dyes, which can be ascribed to the efficient photosensitised electron injection and slow electron recombination. The photocatalytic reaction follows a pseudo-first-order reaction and the rate constant of Ag₂SO₃ for the degradation of rhodamine B is estimated to be 1.7 times that of commercial TiO₂. The stability of unstable Ag₂SO₃ was remarkably enhanced by the addition of Na₂SO₃. The h⁺ and ·O₂^- played relatively major roles during the photocatalytic reaction.