Novel rattle-type magnetic Fe₃O₄@Ag@H-BiOCl photocatalyst with enhanced visible light-driven photocatalytic activity

A novel rattle-type magnetic Fe₃O₄@Ag@H-BiOCl nanocomposite was prepared successfully by a facile solvothermal method. The structures, morphologies, magnetic and electronic properties and photocatalytic performance of as-prepared products were successfully characterized by multiple techniques. The results show that the composites exhibit an obvious cavity, excellent magnetic properties, largely increased electron–hole separation efficiency and visible-light absorption. Due to the existence of an inner cavity, this novel photocatalyst exhibits excellent adsorption and transfer performance to organic pollutants in aqueous systems. The photocatalytic activity of the materials was evaluated by the photocatalytic degradation of rhodamine B (RhB) and antibiotic agent ciprofloxacin (CIP). It was found that the Fe₃O₄@Ag@H-BiOCl exhibited much better photocatalytic performance than pure BiOCl, which displayed the degradation rates of RhB and CIP were 99.5 and 98.3% after 120 min under visible light irradiation, respectively. The enhanced photocatalytic activities may result from the synergetic promoting effect of surface plasmon resonance of Ag and facet-dependent oxygen vacancy of BiOCl, which significantly improves visible-light absorption capacity and separation rate of charge carriers. A possible mechanism of the enhancement of visible photocatalytic activity was proposed. This study provides a promising approach to improve visible-light-response and recycle photocatalysts to treat waste water.