Nonhydrolytic sol-gel in-situ synthesis of novel recoverable amorphous Fe2TiO5/C hollow spheres as visible-light driven photocatalysts

Abstract

A novel recoverable visible-light photocatalyst, amorphous Fe2TiO5/C composite, was prepared via nonhydrolytic sol-gel method with carbon-containing precursors as in-situ carbon sources. It is demonstrated that the precursors, iron ethoxide and butyl titanate, react to form Fe-O-Ti bonds in gel through a ether elimination reaction and amorphous Fe2TiO5 at 300 °C, which finally crystallizes at 600 °C. The residual organic groups form uniform-doped C. Interestingly, the photocatalytic activity of amorphous Fe2TiO5/C is distinctly superior to those of its crystalline counterparts without C and P25 (43-fold increase and 12-fold increase, respectively), which is mainly attributed to the incorporation of C (8.17 wt%) and amorphous Fe2TiO5 with a hollow spherical structure and a high BET surface area of 195.5 m2/g. Importantly, the photocatalyst can be recovered with a recovery rate of 100% simply by an external magnetic field, making it have promising applications in the wastewater treatment field.