Facile preparation of mesoporous TiO2(B) nanowires with well-dispersed Fe2O3 nanoparticles and their photochemical catalytic behavior

Abstract

We report a facile impregnation–solvothermal method for the preparation of mesoporous TiO2(B) nanowires (TNWs(B)) supporting with Fe2O3 nanoparticles (NPs). Open tunnel and porous structure of TNWs(B) provided a confined micro-environment for the stabilization of well-dispersed nanoparticles. The intact fibrous morphology structure, high crystallinity and porosity were remained for TNWs(B) after supporting by nanoparticles. UV−visible DRS analysis indicated that the loading of Fe2O3 on TNWs(B) promoted light harvesting ability and further extended the absorption range. The photocatalytic experiments showed that Fe2O3/TNWs(B) had remarkable catalytic activity for photochemical oxidation of organic pollutants Direct Red 4BS in presence of H2O2 and exhibited excellent tolerance with respect to organic matter poisoning, which was attributed to favorable synergetic effect of Fe2O3 NPs and TNWs(B) support. Compared with P25, the composite material taking the advantage of fibrous morphology was more easily separated from reaction system simply by sedimentation. Moreover, the greatest interest of our finding would be exploring that impregnation duration had significant effect on size and location of NPs supported on TNWs(B). When impregnation duration time was higher than 12h, NPs with d<2nm were highly dispersed in porous nanoarchitecture and had positive effect on catalytic performance, which was due to the facilitation of interfacial photo-generated electrons transfer between (001) planes in TiO2(B) and (113) planes of Fe2O3. The high-degree control over size and location of nanoparticles provides valuable insights for understanding relationship between structure and catalytic activity.