Comparison of Fe₂TiO₅/C photocatalysts synthesized via a nonhydrolytic sol-gel method and solid-state reaction method

Fe₂TiO₅/C photocatalysts were synthesized by a solid-state reaction method (Fe₂TiO₅/C_(S)) and nonhydrolytic sol-gel (NHSG) method (Fe₂TiO₅/C_(N)), where C was introduced by external carbon and in situ carbon sources, respectively. The Fe₂TiO₅/C_(N) photocatalyst with in situ carbon has much better photocatalytic degradation efficiency than that of Fe₂TiO₅/C_(S) synthesized by doping external carbon. The superiorities of in situ carbon were demonstrated by SEM, EDS, BET and photoelectrochemical analysis. Compared with Fe₂TiO₅/C_(S) using external carbon as a carbon source, Fe₂TiO₅/C_(N) with in situ carbon exhibits more uniform elemental distribution, much larger surface area, higher photocurrent density and lower resistivity of interfacial charge transfer. The results show that the introduction of in situ carbon via the NHSG method more easily promotes the separation of photogenerated electron-hole pairs, owing to the uniformity of the carbon element, thereby improving the photocatalytic activity of the photocatalyst.