Construction of α-Fe2O3 Nanorods/UiO-66-NH2 by in-situ Growth with Photocatalytic Reduction of Cr (VI)

Cr (VI) is widely used in industry but its high toxicity causes environmental pollution that needs addressing. The growth of photosensitive materials on semiconductor surfaces can successfully stop photogenerated electron-hole pair recombination, increasing photocatalytic efficiency. Herein, α -Fe 2 O 3 nanorods/UiO-66-NH 2 compounds were successfully obtained through the in situ solvothermal approach. By using 2-aminoterephthalic acid in the solvothermal treatment of Zr 4+ adsorbed α -Fe 2 O 3 nanorods, the UiO-66-NH 2 nanocrystals were evenly distributed on the nanorods. In addition, the reduction efficiency of wastewater reached 93% after 150 min of light exposure, much higher than uncompounded materials. Moreover, the α -Fe 2 O 3 /UiO-66-NH 2 crystals had good regeneration ability, retaining 73% of Cr (VI) removal capacity after four cycles. In this process, α -Fe 2 O 3 and UiO-66-NH 2 effectively complexed to form a heterojunction, which effectively suppressed the complexation of electrons (e − ) and holes (h + ). This efficient complex facilitates the photocatalytic degradation of highly noxious Cr (VI) to Cr (III) under visible light. The efficient Cr (VI) elimination ability comes from the photocatalytic reduction mechanism where they form a special interface to promote the movement of electrons and holes for efficient removal. This work provides both a new approach for in situ synthesis and a reference for efficient Cr (VI) elimination.