Preparation of Bi2MoO6/Ti3C2 MXene heterojunction photocatalysts for fast tetracycline degradation and Cr(vi) reduction†
In this work, a new artificial photocatalytic system has been designed based on the two-dimensional (2D) heterojunction of bismuth molybdate (Bi2MoO6)/Ti3C2 MXenes. The strong interface contact and short charge transport distance between Bi2MoO6 and Ti3C2 ensure extraordinary surface and interface charge transfer abilities. The optimized photocatalyst Bi2MoO6/Ti3C2 exhibited the highest photocatalytic activity, and its removal rates for tetracycline hydrochloride (TC) and heavy metal ion Cr(VI) were about 8.8 and 11.2 times that of pristine Bi2MoO6, respectively. DFT simulation calculations revealed that the stronger interaction promotes the polarization charge distribution of Bi2MoO6/Ti3C2, thereby further enhancing the separation and transfer of photoinduced electrons and holes. Meanwhile, Bi2MoO6/Ti3C2 could provide new adsorption sites, which are conducive to the interaction between pollutant molecules and the catalyst. This indicates that efficient charge separation and excellent adsorption in heterojunction photocatalysts play a key role in improving photocatalytic performance.