Facile synthesis of g-C3N4/amine-functionalized MIL-101(Fe) composites with efficient photocatalytic activities under visible light irradiation

g-C3N4/NH2-MIL-101(Fe) composites are successfully fabricated by a facile in situ solvothermal method. The as-prepared samples have been characterized by XRD, FTIR, XPS, FESEM, TEM, DRS and PL analysis. Under visible light irradiation, the g-C3N4/NH2-MIL-101(Fe) composite shows higher photocatalytic activities than bare g-C3N4 and NH2-MIL-101(Fe) for Cr(VI) reduction and MO degradation. The improved photocatalytic performances are ascribed to the efficient charge separation and transfer on the interface between g-C3N4 and NH2-MIL-101(Fe). Control experiments show that the pH value is vital for Cr(VI) reduction, and meanwhile, the addition of hole scavengers promotes the photocatalytic reduction significantly. Finally, a possible reaction mechanism had also been investigated in detail.