One-step facile synthesis of shell-pearl structured photocatalysts for efficient removal of selected PPCPs from wastewater

Abstract There is an enlightening phenomenon in nature where mussels can purify water following swallowing microorganisms, debris, gravel, etc. Inspired by this phenomenon, we simulated the shell-pearl structure of a clam, and developed a unique method to synthesize Bi2O3 intercalated bismuth titanate and molecularly imprinted TiO2 microbead composites. Salicylic acid (SA) as an organic molecule (also target pollutant) plays a key role in the protection and formation of Bi2O3, which is key to obtaining the structure of mussel shell. The open shell-pearl bionic structure enables efficient transport of excited electrons across a variety of surface interfaces, while suppressing the complexity of photogenerated carrier that drives photocatalytic efficiency. Results show that the synthesized shell-pearl type catalyst achieved 92.54% degradation efficiency of salicylic acid under 30 min UV irradiation, which is 1.97 times higher than that of TiO2. The high degradation efficiency indicate that pearl type catalyst has promising applications in future environmental purification as well as human health.