Photocatalytic properties of TiO2 and Fe-doped TiO2 prepared by metal organic framework-mediated synthesis

By M. J. Valero-Romero, J. Santaclara, Lide Oar‐Arteta, L. V. Koppen, D. Osadchii, Jorge Gascon, F. Kapteijn. Chemical Engineering Journal, 2019

173 citations recorded by the source corpus.

Abstract The Ti-containing metal organic framework (MOF) MIL-125 has been used as sacrificial precursor to obtain TiO2 materials through the MOF-mediated synthesis route. In this study, Fe3+ was deposited on the surface of MIL-125 after its hydrothermal synthesis. Targeted Fe-doped titania photocatalysts were prepared through the direct calcination in air of Fe/MIL-125 crystals and/or by using a two-step method, including carbonization in inert atmosphere followed by calcination in air. The relationship between the synthesis conditions and the properties of the Fe-doped titania nanopowders, such as Fe content, porosity, phase composition and particle size was investigated. From elemental mapping, X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, UV–Vis absorption spectroscopy and photoluminescence emission spectra, the presence of highly dispersed Fe3+ ions incorporated into the TiO2 crystal lattice was confirmed, which led to a significant red shift of photoresponse towards visible light and reduced the recombination rate of electron-hole pairs at low iron content. By varying the pre-carbonization temperature, both crystal size and phase composition in the final materials were modulated. The performance of Fe-doped titania materials in photocatalytic water-splitting was tested for hydrogen evolution. Optimal photocatalytic performance was found at 0.15 and 0.5 wt% iron concentration and exceeded those of non-doped titania and commercial anatase both under visible and UV light irradiation, respectively, and among the highest reported in literature for these systems.

Subfields: Inorganic Chemistry, Materials Chemistry, Renewable Energy, Sustainability and the Environment

View Paper: https://www.semanticscholar.org/paper/ea33844756160cbd232577b968a7ac00c134d8de