Effect of polarization electric field in photodegradation over ε-Cd(IO3)2 photocatalyst against antibiotics and dyes

Abstract

The efficient photogenerated carriers separation is the key factor in enhancing the activity of photocatalysts to solve environmental pollution problems. The internal polarized electric fields in polar materials most likely provide a more direct and stronger driving force for photogenerated carriers separation. Here, we investigate polar ε-Cd(IO3)2 (CIO) with two different morphologies as an efficient photocatalyst for the photodegradation of antibiotics and dyes. According to the theoretical calculation of the ratios of mh*/me* along three different crystal axis directions, the photogenerated carrier separation efficiency along the c-axis direction is the largest, which matches the direction of the polarized electric field in the crystal. The internal polarized electric field promotes the separation of photogenerated carriers, leading to a high transfer efficiency of the catalyst. Moreover, photodegradation experiments demonstrate that the photocatalytic activity of CIO-1 is approximately 3 times that of TiO2 P25. This study provides some insights that might aid the development of polar photocatalysts with superior performance.