MIL-53(Fe)/polyaniline (PANI) composite was prepared by

in situ

depositing PANI on the surface of MIL-53(Fe) and their catalytic performances on the simultaneous removal of RhB and Cr(VI) were investigated. The elimination efficiency of both RhB and Cr(VI) reached more than 98% under pH=2 where hydrochloric acid and citric acid were used to adjust the pH. The results indicated that MIL-53(Fe)/PANI revealed an obvious pH response to the degradation of RhB

while citric acid promoted the Cr(VI) photoreduction. UV-Vis spectra

EIS

and photocurrent response experiments showed that MIL-53(Fe)/PANI had a better light response and carrier migration ability than MIL-53(Fe). The transient absorption spectra also exhibited that the lifetimes of photo-generated carriers were prolonged after the conductive polymer deposition on the MIL-53(Fe) surface. Scavenger experiments demonstrated that the main active species were ·O

2

-

and OH. Combined with activity evaluation results

and the possible photocatalytic mechanism of MIL-53(Fe)/PANI on RhB oxidation and Cr(VI) reduction was proposed

. The addition of conductive polymer can effectively improve the light response of the catalyst under acidic conditions

and meanwhile citric acid also provided a new mediation for the synergistic degradation of multiple pollutants. Good activity and stability of the catalysts made the scale-up purification of acid water feasible under UV-Vis light.