Facile synthesis of Bi2WO6/Bi2MoO6 Z-scheme heterojunction for dye degradation and Cr(VI) reduction

Dyeing wastewater has been one of the severe pollutant crises along the textile industry development, and the design of effective photocatalysts is the attractive strategy for wastewater remediation. Herein, Bi2WO6/Bi2MoO6 microspheres with the high surface area of 12.16 m2/g were prepared by the solvothermal synthesis method, and the hybrid photocatalyst exhibited outstanding solar absorption, photoelectric conversion and photocatalytic performances. The photoelectric tests indicated that the sample photoelectrode exhibite high transient visible light-driven photocurrent value (1.91 mu A/cm2) and low interface resistance. The photocatalytic rate constants for rhodamine B (RhB), methylene blue (MB) photodegradation achieved 1.65 x 10-2 min-1 and 3.78 x 10-2 min-1. The main active species for dye photodegradation were center dot O2 radicals, and the preparation and photocatalytic mechanisms were proposed. Furthermore, the as-prepared photocatalyst also showed high photoremoval of Cr (VI) under visible light irradiation, and the high photocatalytic efficiency (68.57%) was obtained after 160 min irradiation. The excellent photoelectrochemical performance was mainly ascribed to the outstanding photo-electron separation and transportation from Z-scheme heterojunction structure construction. The investigation about Bi2WO6/Bi2MoO6 photocatalysts would provide a feasible route for novel photocatalyst design toward photocatalytic dyeing wastewater purification.