Construction of novel TiO2/Bi4Ti3O12/MoS2 core/shell nanofibers for enhanced visible light photocatalysis

TiO 2 /Bi 4 Ti 3 O 12 hybrids have been widely prepared as promising photocatalysts for decomposing organic contaminations. However, the insufficient visible light absorption and low charge separation efficiency lead to their poor photocatalytic activity. Herein, a robust methodology to construct novel TiO 2 /Bi 4 Ti 3 O 12 /MoS 2 core/shell structures as visible light photocatalysts is presented. Homogeneous bismuth oxyiodide (BiOI) nanoplates were immobilized on electrospun TiO 2 nanofiber surface by successive ionic layer adsorption and reaction (SILAR) method. TiO 2 /Bi 4 Ti 3 O 12 core/shell nanofibers were conveniently prepared by partial conversion of TiO 2 to high crystallized Bi 4 Ti 3 O 12 shells through a solid-state reaction with BiOI nanoplates, which is accompanied with certain transition of TiO 2 from anatase to rutile phase. Afterwards, MoS 2 nanosheets with several layers thick were uniform decorated on the TiO 2 /Bi 4 Ti 3 O 12 fiber surface resulting in TiO 2 /Bi 4 Ti 3 O 12 /MoS 2 structures. Significant enhancement of visible light absorption and photo-generated charge separation of TiO 2 /Bi 4 Ti 3 O 12 were achieved by introduction of MoS 2 . As a result, the optimized TiO 2 /Bi 4 Ti 3 O 12 /MoS 2 -2 presents 60% improvement for photodegrading RhB after 120 min irradiation under visible light and 3 times higher of apparent reaction rate constant in compared with the TiO 2 /Bi 4 Ti 3 O 12 . This synthetic method can also be used to establish other photocatalysts simply at low cost, therefore, is suitable for practical applications.