Synthesis of BiOCl0.5I0.5/TiO2 heterojunctions with enhanced visible-light photocatalytic properties

In this paper, a series of BiOCl0.5I0.5/TiO2 photocatalysts were in situ synthesized by a simple mixed solvothermal method with the aid of lactic acid. The structures and morphologies of as-prepared samples were characterized by XRD, SEM, BET, and DRS. The results of visible light degradation for methyl orange (MO) demonstrated that the BiOCl0.5I0.5/TiO2 heterojunctions assembled by nanosheets were possessed of enhanced photocatalytic activity, comparing with pure BiOCl0.5I0.5 and TiO2. Especially, the composite in which the mass percent of TiO2 was 5.98% exhibited the most excellent photocatalysis among the prepared heterojunctions, the degradation efficiency of which reached 98% under visible light irradiation for 3 h. The remarkably enhanced photocatalytic activities of BiOCl0.5I0.5/TiO2 heterojunctions were attributed to the good adsorption capacity of MO, suitable bandgap, quick charge separation, and transfer of P-N junction heterostructure. The corresponding photocatalytic mechanism was proposed to further explain the photocatalysis process.