American Chemical Society
Browse

Intimate Coupling AgI/AgIO3 Heterojunction Photocatalysts with Excellent Visible-Light-Driven Photocatalytic Activity

Download (1.2 MB)
journal contribution
posted on 2021-08-27, 15:42 authored by Chao Zeng, Haojia Ding, Linping Bao, Yujing Su, Zhipeng Wang
Photodegrading toxic organic pollutants in effluents over semiconductor photocatalysts is friendly and promising. The key is to develop a universally powerful and stable photocatalyst. In this work, highly efficient AgIO3@X heterojunction photocatalysts, composed of AgI and AgIO3 two phases, are fabricated via a facile in situ reduction method. AgIO3 is reduced and then AgI is generated on the surface of AgIO3, so the interfacial interaction between AgI and AgIO3 is very intimate. Introduction of AgI on the surface of AgIO3 extends the photoabsorption from an ultraviolet region to a visible region and also greatly improves charge transfer, giving rise to the remarkedly enhanced photocatalysis activity under visible-light excitation over AgIO3@X samples relative to the pristine AgIO3. The methyl orange (MO) photodegradation rate constant of the optimal AgIO3@20% photocatalyst reaches 0.175 min–1 under visible-light illumination (λ > 420 nm), about 86.5-fold enhanced compared with the pristine counterpart, outperforming most of previously reported state-of-the-art photocatalysts. Particularly, after 20 min of natural sunlight irradiation with a light intensity of 13.8 mW/cm2, the AgIO3@20% sample can rapidly decompose 81.1% of MO. The as-obtained composite photocatalysts also exhibit excellent photocatalytic activity against rhodamine B (RhB) and 2,4-dichlorophenol (2,4-DCP) under the illumination of visible light. The possible reaction pathways and the MO degradation mechanism have been systematically investigated and illustrated. The study paves a new way for designing and developing efficient visible-light-driven photocatalysts with an intimate interfacial interaction.

History