Porous hollow Ag/AgS/AgPO nanocomposites as highly efficient heterojunction photocatalysts for the removal of antibiotics under simulated sunlight irradiation.

Antibiotic pollutants are a serious and growing threat to human health and the environment that efficient measures must be taken to eliminate them. Here, we report the facile fabrication of porous hollow Ag/AgS/AgPO heterostrucutres for efficient photocatalytic degradation of tetracycline under simulated sunlight irradiation. The morphology manipulation and hetero-nanocomposites construction through a coprecipitation-refluxing approach were applied to enhance the photocatalytic performance of the Ag/AgS/AgPO products. The photodegradation outcomes indicated that the heterojunction Ag/AgS/AgPO photocatalyst with a suitable band gap energy of 2.17 eV, has better degradation performance (∼95%) than individual AgS and AgPO structures after 120 min of simulated sunlight irradiation, even after five recycles. The good photocatalytic activity of Ag/AgS/AgPO nanocomposites could be mainly attributed to the unique hierarchical architectures, promoted visible-light harvesting, reduced a recombination and boosted separation of electron-hole pairs originated from the as-formed heterojunctions. Moreover, we proposed a photocatalytic degradation mechanism based on the radical scavenging results, which disclosed that the O and OH species perform essential tasks for the photodegradation of antibiotics by Ag/AgS/AgPO nanocomposites.