Ti3+ self-doped TiO2 nanotubes photoelectrode decorated with Ar-Fe2O3 derived from MIL-100(Fe): Enhanced photo-electrocatalytic performance for antibiotic degradation

The low interfacial mass transfer efficiency between metal-organic framework (MOFs) and conductive substrates makes the development of MOFs-based photoelectrodes challenging. Herein, Ar-Fe2O3/Ti3+-TiO2-NTs photoelectrodes are obtained through electrochemical reduction, pulsed deposition, MOFs self-assembly, and sculptural reduction processes. The target photoelectrodes achieve 100% degradation of tetracycline (TC) within 90 min, and the photo-electrocatalytic synergy factor is estimated to be 4.20. Ar-Fe2O3/Ti3+-TiO2-NTs photoelectrodes also exhibit excellently in multiple antibiotics and real samples. The reduction self-doping of Ti3+ retains vertical orientation properties of nanotubes to provide a path for electronics, and heightens the light-harvesting capacity. The pulse deposition improves the dispersibility of Fe, which is beneficial to the self-assembly of MIL-100(Fe). After sculpture-reduction processes, Ar-Fe2O3 retains the porous structure of MIL-100(Fe), and the heterojunction formed with Ti3+-TiO2-NTs can significantly enhance the interface charge transfer. This work enriches the electrochemical modification strategy of TiO2-NTs, and gives new insights into the development of MOFs-based photoelectrodes.