Fe-doped zirconia nanoparticles with highly negative conduction band potential for enhancing visible light photocatalytic performance

Maintaining a highly negative value of conduction band (CB) potential of photocatalysts through metal doping has been a great challenge. Herein, we investigated the effects of Fe-doping on the crystal structures and electronic structures of zirconia (ZrO 2 ) in detail by combining experiments and Density Functional Theory (DFT). It was revealed that the Fe-doping obviously triggered the formation of tetragonal phase ZrO 2 and induced a defect states in the bandgap of Fe-doped ZrO 2 . Due to the coherent effect between the electrons of the Fe 3 d orbitals and ZrO 2 intrinsic electronic states, the defect states expanded the light absorption edge of ZrO 2 and Fe-doped ZrO 2 showed a small bandgap with maintaining a highly negative value of the CB potential. Meanwhile, Fe-doping significantly enhanced photoelectrochemical properties, the efficiency separation of electron-hole pairs and photocatalytic activity in comparison with the pristine ZrO 2 . We also found that 0.5%Fe-ZrO 2 exhibited the optimum photocatalytic performance, and reached 96% for degradation of Rhodamine B (RhB) within 150 min under visible light irradiation. This work elucidated the mechanism of the photocatalytic degradation of RhB over Fe-doped ZrO 2 and provided a promising approach in designing highly negative CB potential of ZrO 2 via Fe doping toward sustainable environmental remediation.