Fabrication of Bi2S3/MOFs composites without noble metals for enhanced photoreduction of Cr (VI)

Constructing heterojunction has been widely accepted as an effective method to improve photocatalytic activity. Herein, Bi2S3 modified NH2-UiO-66 composites were prepared by facile hydrothermal reactions. The as-prepared NH2-UiO-66/Bi2S3 hybrids enhanced Cr (VI) photoreduction under simulated sunlight, which is due to the efficient separation of charge carriers. UV–vis DRS confirms the expansion of light absorption in visible light region and PL spectra proves the excellent separation of electron-hole pairs. Influence factors on Cr (VI) reduction such as the amount of Bi2S3 in photocatalysts, initial solution pH and the presence of organic dyes were also explored. 30NUB exhibited the best reduction effect among the YNUB series and acidic condition is favorable for Cr (VI) reduction. It is worth mentioning that a mutual promotion on Cr (VI) removal and dye degradation was also realized in Cr (VI)/dye mixed solution.