Efficient visible-light responsive TiO2 nanoparticles incorporated magnetic carbon photocatalysts

We developed a photocatalyst (T-FC) that incorporated anatase TiO2 (T) nanoparticles on magnetically enhanced carbon [iron oxide (F; alpha,gamma-Fe2O3-Fe3O4) supported on activated carbon (C)] for use as a highly visible-light-active, low-cost, recyclable, and photostable catalyst for the degradation of organic dyes and bacterial sterilization. The T-FC photocatalyst with a large Brunauer-Emmett-Teller surface area (564.3 m(2) g(-1)) was synthesized by wet-chemical processing and ultrasound irradiation. Under visible-light irradiation, the highest photocatalytic activity for T-FC ([k] = 3.874 h(-1)) was 32.6 and 3.1 times higher than those of T ([k] = 0.119 h(-1)) and FC ([k] = 1.259 h(-1)). The recyclability of T-FC was high, with a dye decolorization rate measured at similar to 95.8% of the initial value after 15 recycles. Furthermore, T-FC showed more substantial antimicrobial properties against both Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) than T and FC when exposed to visible-light for 120 min. Even after 10 cycles of use, T-FC killed more than 95.7% of E. coli. These results indicated that T-FC might have utility in several promising applications such as wastewater treatment and as a bactericidal agent. (C) 2013 Elsevier B.V. All rights reserved.